STATE OF OHIO

Department of Transportation

Construction Administration

Manual of Procedures

Columbus, Ohio

2013

2013 Construction Administration Manual of Procedures

Ohio Department of Transportation

Division of Construction Management

1980 W. Broad Street

Columbus, OH 43223

Web address:

ODOT: http://www.dot.state.oh.us

To purchase a copy, contact the ODOT Office of Contracts

at the above address, or by phone at 1-800-459-3778.

An Equal Opportunity Employer

Table of Contents

Foreword.. 1

Introduction to Construction Administration and Inspection   2

General Documentation Requirements. 3

Project Records. 3

General Guidelines for Documentation. 4

Substantiation. 4

Validation. 5

Filing. 5

List of Forms. 6

101 Definitions and Terms. 9

General. 9

Flexible Pavement Terms. 13

Concrete Terms. 17

Rigid Pavement Terms. 21

Earthwork. 26

Landscape. 31

105 Control of the Work.. 33

Overview of Construction Contracts – General ODOT Organization. 33

Central Office. 33

District 34

Other Agencies. 36

Administration of Construction Contracts at the Project Level. 37

Authority / Responsibilities of the Engineer (105.01) 37

Authority / Responsibilities of the Inspector (105.09) 38

Authority / Responsibilities of the Contractor. 39

Coordination of the Contract Documents (105.04) 40

Proposal 40

Plans. 40

Working Drawings. 41

Construction and Material Specifications. 41

Cooperation with Utilities (105.07) 41

Haul Roads (105.13) 42

Borrow and Waste Areas (105.16) 42

Construction and Demolition Debris (105.17) 44

106 Control of Materials. 48

General. 49

Material Documentation Process. 49

Procedures. 50

Quality Assurance Reviews. 50

Unacceptable Material (106.07) 51

Delivered Material 51

Samples, Tests, and Cited Specifications (106.02) 51

Flexible Pavement 51

Aggregate. 52

Liquid Asphalt Materials. 52

Asphalt Concrete. 53

Sources of Additional Information and Guidelines for the Control and Conduct of the Work  53

107 Legal Relations and Responsibility to Public.. 54

107.01 Laws to be Observed. 54

General 54

Definitions. 55

Prevailing Wage. 62

Equal Employment Opportunity Contract Compliance. 77

Disadvantaged Business Enterprise (DBE) 109

Encouraging Diversity, Growth & Equity (EDGE) 118

107.10 Protection and Restoration of Property. 121

107.11 Contractor’s Use of the Project Right-of-Way or Other Department Property  122

General 122

Borrowing and/or Wasting on the Right-of-Way (107.11.A) 122

Portable Plants within the Project Limits (107.11.B &107.11.C) 123

Equipment Storage and Staging (107.11.D) 123

Documentation Requirements - Waste and Borrow Sites (105.16, 105.17 and 107.11) 123

108 Prosecution and Progress. 126

Partnering (108.02) 126

Preconstruction Meeting (108.02.A) 126

Initial Partnering Session (108.02.B) 128

Facilitated Partnering (PN 111) 129

Progress Meeting (108.02.C) 130

Post-Milestone Meeting (108.02.D) 130

Partnering Monitoring (108.02.E) 130

Mitigation and Notice (108.02.F) 131

Dispute Resolution and Administrative Claims Process (108.02.G) 131

Post Construction Meeting (108.02.H) 138

Partnering Close-Out Survey (108.02.I) 138

Progress Schedule (108.03.A) 138

Reviewing and Accepting the Contractor's Schedule. 139

Schedule Updates. 139

Determination of a Time Extension (108.06) 140

Procedure to Analyze a Request for Time Extension. 140

Behind Schedule. 141

Delays (108.06) 142

Duty to Mitigate Delays (108.06.A) 143

Waiver of Liquidated Damages (108.07) 143

Procedure to Waive Liquidated Damages. 143

Documentation Requirements – Waiver of Liquidated Damages. 144

Termination. 144

Termination for Convenience (108.09) 144

Termination by Default (108.08) 144

109 Method of Measurement and Payment.. 145

General. 145

Changes and Extra Work (109.05) 146

General 146

Procedure for Processing Change Orders. 147

Documentation Requirements – Change Orders. 162

Reasons for Change. 163

Common Change Order Elements. 164

Change Order Pricing. 165

Additional Contract Time for Extra Work. 166

Record Keeping. 166

Quantity Measurements. 166

Force Account Work and Extra Work Using Force Account Style Analysis. 166

Estimates (109.09) 167

General 167

Daily Diary. 167

Procedure for Payment of Estimates. 168

Documentation Requirements – Estimates. 170

Project Approval of Estimates. 170

District Office Approval of Estimates. 172

Method of Measurement 172

Basis of Payment 173

Partial and Final Acceptance (109.11 and 109.12) 174

Completion of Contract Requirements. 174

Final Inspection (109.12.A) 174

Determination of Final Contract Value (109.12.C) 181

Final Payment (109.12.D) 183

Release Contractor from Further Responsibility (109.12.E) 183

200 Earthwork.. 184

201 Clearing and Grubbing.. 184

General 184

Disposal of Materials. 184

Plan Notes. 185

Trees Located within the Plan Limits Allowed to Remain. 186

Scalping (201.04) 186

Documentation Requirements - 201 Clearing and Grubbing. 187

202 Removal of Structures and Obstructions. 188

Structures Removed (202.03) 188

Pipe Removal (202.04) 189

Pavement, Walks, Curbs, Steps, Gutters, or Traffic Dividers Removed (202.05) 190

Buildings Demolished (202.06) 191

Underground Storage Tanks Removed (202.08) 192

Regulated Waste Requirements. 195

Other Wastes and Environmental Considerations. 208

Slag Use on the Projects. 208

Method of Measurement / Basis of Payment (202.13 and 202.14) 222

Documentation Requirements - 202 Removal of Structures and Obstructions, and Regulated Waste Requirements  222

203 Roadway Excavation and Embankment.. 226

Introduction. 226

Importance of Proper Embankment Construction. 226

Importance of Proper Excavation. 229

Materials (203.02) 230

Restrictions (203.03) 257

General Construction (203.04) 257

Embankment Construction Methods (203.05) 260

Benching. 267

Spreading and Compacting (203.06) 276

Compaction and Moisture Requirements (203.07) 280

Method of Measurement (203.09) 282

Basis of Payment (203.10) 292

Documentation Requirements - 203 Roadway Excavation and Embankment 296

204 Subgrade Compaction and Proof Rolling.. 298

Importance. 298

Specification and Plan Requirements. 298

Subgrade Correction Prior to Proof Rolling. 298

Drainage and Hauling. 299

When to Proof Roll 301

Proof Rolling (204.06) 302

Investigation. 306

Implementation during Construction. 314

Documentation Requirements - 204 Subgrade Compaction and Proof Rolling. 315

205 Chemically Stabilized Embankment.. 316

Uses of Chemically Stabilized Embankment 316

Materials (205.02) 316

Construction (205.04) 317

Mixture Design for Chemically Stabilized Soils (205.05) 320

Method of Measurement (205.06) 320

Documentation Requirements - 205 Chemically Stabilized Embankment 320

206 Chemically Stabilized Subgrade.. 320

Uses and Application for Chemically Stabilized Subgrade. 320

Materials (206.02) 321

Test Rolling (206.04) 321

Construction (206.05) 322

Mixture Design for Chemically Stabilized Soils (206.06) 327

Method of Measurement (206.07) 327

Documentation Requirements - 206 Chemically Stabilized Subgrade. 327

208 Rock Blasting.. 328

General Information. 328

Rock Blasting Basics. 328

Vibration and Air Blast Monitoring (208.15 and 208.16) 333

Presplitting (208.09) 334

Documentation Requirements - 208 Rock Blasting. 335

209 Linear Grading.. 336

Documentation Requirements - 209 Linear Grading. 336

250 Pavement Repairs. 337

251 Partial Depth Repair.. 337

Description (251.01) 337

Removal of Existing Pavement (251.02) 337

Placement of Asphalt Concrete (251.03) 337

Documentation Requirements - 251 Partial Depth Pavement Repair. 338

252 Full Depth Rigid Pavement Removal and Flexible Replacement   339

Description (252.01) 339

Removal of Existing Pavement (252.02) 339

Correction of Subgrade (252.03) 340

Placement of Asphalt Concrete (252.04) 340

Documentation Requirements - 252 Full-Depth Rigid Removal and Flexible Replacement 341

253 Pavement Repair.. 342

Description (253.01) 342

Removal of Existing Pavement (253.02) 342

Placement of Asphalt Concrete (253.03) 342

Documentation Requirements - 253 Pavement Repair. 343

254 Pavement Planing.. 344

Description (254.01) 344

Equipment (254.02) 344

Planing (254.03) 344

Surface Patching (254.04) 345

Surface Tolerances (254.05) 345

Method of Measurement and Basis of Payment (254.06, 254.07) 345

Documentation Requirements - 254 Pavement Planing. 345

255 Full Depth Pavement Removal and Rigid Replacement.. 346

General 346

Description (255.01) 346

Materials (255.02) 346

Removal of Existing Pavement (255.03) 347

Correction of Subgrade (255.04) 350

Placing Dowels and Tiebars (255.05) 352

Placement of Portland Cement Concrete (255.06) 356

Wearing Course Replacement (255.07) 358

Opening to Traffic (255.08) 359

Method of Measurement (255.09) 359

Basis of Payment (255.10) 359

Documentation Requirements - 255 Full Depth Pavement Removal and Rigid Replacement 360

256 Bonded Patching of Portland Cement Concrete Pavement   361

General 361

Description (256.01) 361

Materials (256.02) 361

Equipment (256.03) 362

Removal of Unsound Concrete (256.04) 362

Preparation of Patch Area (256.05) 365

Bonding Grout Installation (256.06) 365

Placing Patching Material (256.07) 366

Curing and Loading (256.08) 370

Method of Measurement (256.09) 370

Basis of Payment (256.10) 370

Documentation Requirements - 256 Bonded Patching of Portland Cement Concrete Pavement 370

257 Diamond Grinding Portland Cement Concrete Pavement.. 371

Description (257.01) 371

Equipment (257.02) 371

Construction (257.03) 373

Final Surface Finish (257.04) 373

Method of Measurement (257.05) 375

Basis of Payment (257.06) 375

Documentation Requirements - 257 Diamond Grinding Portland Cement Concrete Pavement 376

258 Dowel Bar Retrofit.. 377

General 377

Description (258.01) 377

Equipment (258.03) 377

Construction (258.04) 379

Method of Measurement (258.05) 385

Basis of Payment (258.06) 385

Documentation Requirements - 258 Dowel Bar Retrofit 385

300 Bases. 386

301 Asphalt Concrete Base.. 386

Description (301.01) 386

Composition (301.02) 386

Spreading and Finishing (301.04) 386

Hauling. 387

Compaction. 387

Spreading and Surface Tolerances (301.05) 388

Documentation Requirements - 301 Asphalt Concrete Base. 389

302 Asphalt Concrete Base.. 390

Description (302.01) 390

Composition (302.02) 390

Spreading and Finishing (302.04) 390

Hauling. 391

Compaction. 391

Spreading and Surface Tolerances (302.05) 392

Documentation Requirements - 302 Asphalt Concrete Base. 392

304 Aggregate Base.. 394

Materials (304.02) 394

Before Spreading (304.03) 395

Spreading (304.04) 395

Compaction (304.05) 398

Finished Surface (304.06) 400

Documentation Requirements - 304 Aggregate Base. 402

305 Portland Cement Concrete Base.. 403

Construction (305.02) 403

Method of Measurement (305.03) 403

Basis of Payment (305.04) 403

Documentation Requirements - 305 Portland Cement Concrete Base. 403

308 Asphalt Treated Free Draining Base.. 405

320 Rubblize and Roll.. 406

Description (320.01) 406

Materials (320.03) 406

Equipment (320.03) 406

Construction Details (320.04) 406

Method of Measurement (320.05) 408

Documentation Requirements - 320 Rubblize and Roll 408

321 Cracking and Seating Existing Plain Concrete Pavement.. 409

Description (321.01) 409

Equipment (321.02) 409

Construction Details (321.03) 409

Documentation Requirements - 321 Cracking and Seating Existing Plain Concrete Pavement 410

400 Flexible Pavement.. 411

401 Asphalt Concrete Pavements – General.. 411

General Description. 411

Requirements for Mix Design, Materials, Rap, Mixing Plants (401.02 through 401.05) 412

Weather Limitations (401.06) 412

Notification (401.07) 414

Hauling (401.11) 414

Spreading Equipment (401.12) 415

Rollers (401.13) 416

Conditioning Existing Surface (401.14) 418

Spreading, Finishing, and Night Work (401.15) 420

Compaction (401.16) 437

Joints (401.17) 441

Spreading and Surface Tolerances (401.19) 443

Method of Measurement (401.21) and Basis of Payment (401.22) 447

Documentation Requirements - 401 Asphalt Concrete Pavements-General 449

407 Tack Coat.. 450

Description (407.01) 450

Materials (407.02) 450

Equipment (407.03) 451

Weather Limitations (407.04) 453

Preparation of Surface (407.05) 453

Application of Asphalt Material (407.06) 454

Method of Measurement (407.07) and Basis of Payment (407.08) 456

Documentation Requirements - 407 Tack Coat 457

408 Prime Coat.. 458

Description (408.01) 458

Asphalt Material (408.02) 458

Cover Aggregate (408.03) 458

Weather Limitations (408.04) 458

Equipment (408.05) 458

Preparation of Surface (408.06) 459

Application of Asphalt Material (408.07) 459

Application of Cover Aggregate (408.08) 459

Method of Measurement (408.09) 459

Documentation Requirements - 408 Prime Coat 459

409 Sawing and Sealing Asphalt Concrete Pavement Joints. 461

Materials (409.02) 461

Construction Details (409.03) 461

Documentation Requirements - 409 Sawing and Sealing Asphalt Pavement Joints. 462

410 Traffic Compacted Surface.. 463

Documentation Requirements - 410 Traffic Compacted Surface. 463

411 Stabilized Crushed Aggregate.. 464

Documentation Requirements - 411 Stabilized Crushed Aggregate. 464

421 Microsurfacing.. 465

Description (421.01) 465

Materials (421.02) 465

Proportioning (421.03) 465

Weather Limitations (421.04) 465

Mixing Equipment (421.05) 465

Equipment Calibration (421.06) 466

Spreading Equipment (421.07) 466

Surface Preparation (421.08) 467

Test Strip (421.09) 467

Application (421.10) 467

Acceptance (421.11), Method of Measurement (421.12), Payment (421.13) 468

Documentation Requirements - 421 Microsurfacing. 470

422 Chip Seal.. 471

Description (422.01) 471

Materials (422.02) 471

Equipment (422.03) 472

Weather Limitations (422.04) 477

Test Strip (422.05) 477

Surface Preparation (422.06) 477

Binder Application (422.07) 478

Cover Aggregate Application (422.08) 479

Construction Operation (422.09) 480

Quality Control (422.10) 482

Acceptance (422.11) 484

Method of Measurement (422.12) and Basis of Payment (422.13) 487

Documentation Requirements - 422 Chip Seal with Polymer Binder. 487

423 Crack Sealing, Hot Applied.. 489

Description (423.01) 489

Materials (423.02) 489

Equipment (423.03) 489

Weather Limitations (423.04) 490

Preparation (423.05) 490

Mixing Type II and Type III (423.06) 490

Application of Sealant (423.07) 490

Opening to Traffic (423.08) 491

Method of Measurement (423.09) and Basis of Payment (423.10) 491

Documentation requirements - 423 Crack Sealing Hot Applied. 491

424 Fine Graded Polymer Asphalt Concrete.. 492

General 492

Composition (424.02) 492

Equipment 492

Materials (424.03) 493

Mixing (424.04) 493

Weather Limitations (424.05) 494

Spreading and Finishing (424.06) 494

Acceptance (424.08) 494

Documentation Requirements - 424 Fine Graded Polymer Asphalt Concrete. 495

442 Superpave Asphalt Concrete.. 496

Description (442.01) 496

Acceptance (442.07) 496

Documentation Requirements - 442 Superpave Asphalt Concrete. 496

443 Stone Matrix Asphalt Concrete.. 498

446 Asphalt Concrete.. 499

Description (446.01) 499

Density Acceptance (446.05) 499

Documentation Requirements - 446 Asphalt Concrete. 502

448 Asphalt Concrete.. 503

Description (448.01) 503

Density (448.03) 503

Acceptance (448.05) 506

Documentation Requirements - 448 Asphalt Concrete. 506

450 Rigid Pavement.. 507

451 Reinforced Portland Cement Concrete Pavement.. 507

General 507

Description (451.01) 507

Materials (451.02) 507

Pavement Quality Control (451.03) 509

Equipment (451.04) 510

Setting Forms (451.05) 517

Fine Grading of Subgrade or Subbase (451.06) 518

Placing Concrete (451.07) 520

Placing Reinforcement (451.08) 526

Joints (451.09) 529

Finishing (451.10) 548

Curing (451.11) 552

Removing Forms (451.12) 555

Surface Smoothness (451.13) 556

Profile Grinding (451.14) 558

Pavement Grooving Corrections (451.15) 559

Sealing Expansion Joints (451.16) 559

Opening to Traffic (451.17) 560

Pavement Thickness (451.18.A) 561

Pavement Strength (451.18.B) 562

Price Adjustments (451.19) 563

Method of Measurement (451.20) 566

Basis of Payment (451.21) 566

Documentation Requirements - 451 Reinforced Portland Cement Concrete Pavement 566

452 Non-Reinforced Portland Cement Concrete Pavement.. 568

Description (452.01) 568

Construction (452.02) 568

Method of Measurement (452.03) 568

Basis of Payment (452.04) 568

Documentation Requirements - 452 Non-Reinforced Portland Cement Concrete Pavement 569

455 Quality Control Plan, Testing, and Assurance for QC/QA Concrete   570

Description (455.01) 570

Quality Control Plan Basic Requirements (455.02) 570

Additional Quality Control Plan Requirements for Structures (455.03) 570

Additional Quality Control Plan Requirements for Concrete Pavement (455.04) 571

Department Quality Assurance (455.05) 572

QCP Submittal and Corrective Action (455.06) 573

Basis of Payment (455.07) 574

Documentation Requirements - 455 Quality Control Plan, Testing, and Assurance for QC/QA Concrete  574

499 Concrete – General.. 575

Introduction. 575

Duties and Responsibilities. 577

Materials (499.02) 577

Proportioning (499.03 and 499.04) 582

Concrete Classes (499.03) 582

Basics Concepts used in Concrete Quality Control 584

Absolute Volume. 587

Moisture Correction. 589

Job Control Tests. 595

Representative Concrete Samples. 596

Moisture Testing. 597

Slump. 601

Concrete Yield. 607

Total Air Tests (ASTM C 231 or ASTM C 173) 619

Temperature of Freshly Mixed Portland Cement Concrete (ASTM C -1064) 631

Gradation of Aggregate. 632

Making and Handling Concrete Cylinders (ASTM C-31) 633

Making Concrete Test Beams. 637

Care and Maintenance of Concrete Testing Equipment 642

Concrete Mix Adjustments (499.04) 644

Modifying Mix Designs. 649

Equipment for Batching and Mixing Concrete (499.05) 654

Handling, Measuring and Batching Materials (499.06) 657

Mixing Concrete (499.08) 660

Concrete Testing Reports. 663

Check List for Inspection. 671

Documentation Requirements - 499 Concrete. 673

AASHTO M 157. 674

AASHTO M 157 Sections 10, 11.2, 11.5, 11.6. 674

500 Structures. 678

501 Structures - General.. 678

Engineering. 678

Working Drawings and Calculations (501.05) 678

Documentation Requirements - 501 Structures. 679

502 Structures for Maintaining Traffic.. 680

Description (502.01) 680

Design and Construction (502.02) 680

Maintenance (502.03) 681

Documentation Requirements - 502 Structures for Maintaining Traffic. 681

503 Excavation for Structures. 682

Cofferdams and Excavation Bracing (503.03) 682

Approval of Foundations (503.06) 684

Backfill (503.08) 685

Method of Measurement (503.09) 685

Documentation Requirements - 503 Excavation for Structures. 685

504 Sheet Piling Left in Place.. 686

Materials (504.02) 686

Driving (504.03) 686

Documentation Requirements - 504 Sheet Piling Left in Place. 686

505 Pile Driving Equipment Mobilization.. 687

Basis of Payment (505.02) 687

Documentation Requirements - 505 Pile Driving Equipment Mobilization. 687

506 Static Load Test.. 688

Description (506.01) 688

General (506.02) 688

Application of Load (506.03) 690

Documentation Requirements - 506 Static Load Test 693

507 Bearing Piles. 694

Description (507.01) 694

General (507.02) 694

Materials (507.03) 694

Driving of Piles (507.04) 694

Determination of Required Driving Criteria (507.05) 698

Cast-In-Place Reinforced Concrete Piles (507.06) 698

Steel H-piles (507.07) 699

Timber Piles (507.08) 700

Splices (507.09) 700

Defective Piles (507.10) 701

Prebored Holes (507.11) 701

Method of Measurement (507.12) 702

Documentation Requirements - 507 Bearing Piles. 702

508 Falsework and Forms. 704

General 704

Falsework (508.02) 706

Documentation Requirements - 508 Falsework and Forms. 708

509 Reinforcing Steel.. 709

Storage. 709

Care of Material (509.03) 709

Method of Placing (509.04) 709

Splicing (509.07) 711

Supports (509.08) 711

Epoxy Coated Reinforcing Steel (509.09) 712

Method of Measurement (509.10) and Basis of Payment (509.11) 712

Documentation Requirements - 509 Reinforcing Steel 714

510 Dowel Holes. 715

Materials (510.02) 715

Placement (510.04) 715

Documentation Requirements - 510 Dowel Holes. 715

511 Concrete for Structures. 716

Materials (511.02) 716

Concrete (511.03) 716

Quality Control Requirements and Mass Concrete (511.04) 716

Mixing of Concrete (511.05) 717

Slump (511.06) 718

Placing Concrete (511.07) 719

Slipform Construction of Bridge Railing (511.08) 728

Construction Joints (511.09) 729

Work Stoppage (511.10) 729

Depositing and Curing Concrete During Cold Weather (511.12) 730

Removal of Forms (511.13) 733

Curing and Loading (511.14) 733

Surface Finish (511.15) 735

Roadway Finish (511.16) 736

Bridge Deck Grooving (511.17) 739

Sidewalk Finish (511.18) 740

Sealing Joints and Cracks (511.19) 740

Compressive Strength (511.20) 740

Air Content (511.21) 741

Pay Factors (511.22) 742

Method of Measurement (511.23) and Basis of Payment (511.24) 743

Documentation Requirements - 511 Concrete for Structures. 744

512 Treating Concrete.. 746

Description (512.01) 746

Materials (512.02) 746

Sealing of Concrete Surfaces (512.03) 746

Sealing Concrete Bridge Decks with HMWM Resin (512.04) 751

Soluble Reactive Silicate (SRS) Concrete Treatment (512.05) 752

Treating Concrete Bridge Decks with Gravity-Fed Resin (512.06) 752

Sealing Cracks by Epoxy Injection (512.07) 753

Waterproofing (512.08) 753

Documentation Requirements – 512 Treating Concrete. 753

513 Structural Steel Members. 755

General (513.04) 755

Fabricator Documentation Responsibility (513.05) 755

Care of Material (513.10) 755

Workmanship and Straightening (513.11) 755

High Strength Steel Bolts, Nuts, and Washers (513.20) 758

Welding (513.21) 761

Stud Shear Connectors (513.22) 763

Shop Coatings (513.27) 765

Documentation Requirements - 513 Structural Steel Members. 765

514 Painting of Structural Steel.. 766

Description (514.01) 766

Quality Control (514.04) 766

Testing Equipment (514.05) 767

Work Limitations (514.06) 767

Pollution Control (514.08) 768

Inspection Access and Lighting (514.10) 769

Job Site Visual Standards (514.11) 769

Quality Control Point Photographic Verification and Documentation (514.12) 769

Surface Preparation (514.13) 770

Handling (514.15) 773

Mixing and Thinning (514.16) 773

Coating Application (514.17) 774

Removing Fins, Tears, or Slivers (514.18) 776

Caulking (514.19) 776

Dry Film Thickness (514.20) 776

Final Inspection (514.21) 777

Repair Procedures (514.22) 778

Documentation Requirements - 514 Painting of Structural Steel 778

515 Prestressed Concrete Bridge Members. 780

Fabrication Tolerances (515.17) 780

Handling, Storage, Transportation, and Erection (515.18) 780

Documentation Requirements - 515 Prestressed Concrete Bridge Members. 783

516 Expansion and Contraction Joints, Joint Sealers and Bearing Devices  784

Expansion and Contraction Joints (516.05) 784

Joint Sealers (516.06) 784

Bearing Devices (516.07) 785

Documentation Requirements - 516 Expansion & Contraction Joints, Joint Sealers, and Bearing Devices  785

517 Railings. 787

Steel and Iron Railings (517.05) 787

Documentation Requirements - 517 Railings. 787

518 Drainage of Structures. 788

Porous Backfill (518.05) 788

Documentation Requirements - 518 Drainage of Structures. 788

519 Patching of Concrete Structures. 789

Removal of Disintegrated Concrete (519.03) 789

Placing, Finishing, and Curing of Concrete (519.06) 789

Documentation Requirements - 519 Patching Concrete Structures. 789

520 Pneumatically Placed Mortar.. 790

Description (520.01) 790

Reinforcement (520.04) 790

Preparation of Repair Area (520.05) 790

Preconstruction Testing (520.09) 791

Placing (520.10) 791

Inspection and Testing (520.11) 791

Documentation Requirements - 520 Pneumatically Placed Mortar. 792

522 Structural Plate Corrugated Metal Structures on Footings  793

Description (522.01) 793

Quality Control 793

Assembly. 793

Documentation Requirements - 522 Structural Plate Corrugated Metal Structures on Footings  793

523 Dynamic Load Test.. 794

Description (523.01) 794

General (523.02) 794

Documentation Requirements - 523 Dynamic Load Test 796

524 Drilled Shafts. 797

Description (524.01) 797

Contractor's Installation Plan (524.03) 797

Hole Excavation (524.04) 798

Friction Type Drilled Shafts (524.05) 799

Casings (524.06) 800

Slurry (524.07) 800

Excavation Inspection (524.08) 801

Reinforcing Steel for Drilled Shafts (524.09) 801

Concrete for Drilled Shafts (524.10) 801

Tremie (524.12) 801

Pumped Concrete (524.13) 802

Inspection Records (524.15) 803

Method of Measurement (524.16) and Basis of Payment (524.17) 804

Documentation Requirements - 524 Drilled Shafts. 804

526 Approach Slabs. 805

Description (526.01) 805

Materials (526.02) 805

Setting Grades. 805

Dimensions. 806

Documentation Requirements - 526 Approach Slabs. 806

600 Incidentals. 807

601 Slope and Channel Protection.. 807

602 Masonry.. 808

605 Underdrains. 809

Description (605.01) 809

Materials (605.02) 809

Pipe Underdrains Construction (605.03) 810

Construction Underdrains (605.04) 811

Prefabricated Edge Underdrains (605.05) 812

Underdrain Outlets (605.06) 812

Aggregate Drains (605.07) 812

Method of Measurement (605.08) 813

Basis of Payment (605.09) 813

Documentation Requirements - 605 Underdrains. 813

606 Guardrail.. 814

Description (606.01) 814

Setting Posts (606.03) 814

Erecting Rail Elements (606.04) 814

Guardrail Rebuilt (606.05) 815

Impact Attenuators (606.06) 815

Method of Measurement (606.07) 815

Basis of Payment (606.08) 815

Documentation Requirements. 816

607 Fence.. 817

Clearing and Grading (607.03) 817

Post Assemblies (607.04) 817

Horizontal Deflection (607.05) 817

Line Posts (607.06) 817

Fabric (607.07) 818

Method of Measurement (607.09) 818

Documentation Requirements - 607 Fence. 818

608 Walks, Curb Ramps, and Steps. 820

Description (608.01) 820

Concrete Walks (608.03) 820

Curb Ramps (608.07) 820

Method of Measurement (608.08) 820

Documentation Requirements - 608 Walks, Curb Ramps, and Steps. 820

609 Curbing, Concrete Medians, and Traffic Islands. 822

Documentation Requirements - 609 Curbing, Concrete Medians, and Traffic Islands. 822

610 Cellular Retaining Walls. 824

Documentation Requirements - 610 Cellular Retaining Walls. 824

611 Pipe Culverts, Sewers, Drains, and Drainage Structures. 825

Description (611.01) 825

Materials (611.02) 825

Submittals (611.04) 826

Documentation Requirements - 611 Pipe Culverts, Sewers, Drains and Drainage Structures  831

613 Low Strength Mortar Backfill.. 832

Documentation Requirements - 613 Low Strength Mortar Backfill 832

614 Maintaining Traffic.. 833

Description (614.01) 833

Traffic Facilities (614.02) 833

Traffic Control General (614.03) 833

Flaggers (614.08) 834

Asphalt Concrete for Maintaining Traffic (614.13) 834

Performance (614.14) 834

Method of Measurement (614.15) 834

Basis of Payment (614.16) 835

Documentation Requirement – 614 Maintaining Traffic. 836

Daily Documentation Requirements - 614 Maintaining Traffic. 844

615 Roads and Pavements for Maintaining Traffic.. 845

Documentation Requirements - 615 Roads and Pavements for Maintaining Traffic. 845

616 Dust Control.. 846

Documentation Requirements - 616 Dust Control 846

617 Reconditioning Shoulders. 847

Documentation Requirements - 617 Reconditioning Shoulders. 847

618 Rumble Strips on Shoulders. 848

Documentation Requirements - 618 Rumble Strips on Shoulders. 848

619 Field Office.. 849

Documentation Requirements - 619 Field Office. 849

620 Delineators. 850

General 850

Materials (620.02) 850

Layout (620.03) 850

Installation (620.05) 852

Documentation Requirements - 620 Delineators. 852

621 Raised Pavement Markers (RPM) 853

General 853

Materials (621.02) 853

Installation RPM Casting (621.04) 853

Reflector Replacement (621.06) 855

Remedial Actions for Poorly Installed RPM Castings. 857

Raised Pavement Markers Removed. 861

Documentation Requirements - 621 Raised Pavement Markers. 862

622 Concrete Barrier.. 863

Description (622.01) 863

Placing Concrete (622.03) 863

Portable Concrete Barrier (622.04) 863

Joints (622.05) 863

Finish (622.06) 864

Curing (622.07) 864

Method of Measurement (622.08) 864

Basis of Payment (622.09) 865

Documentation Requirements. 865

623 Construction Layout Stakes and Survey Monuments. 866

Description (623.01) 866

Verification. 866

Placement, Protection and Restoration of Survey Monuments. 866

Providing Electronic Instrumentation. 867

Documentation Requirements - 623 Construction Layout Stakes. 867

624 Mobilization.. 868

Documentation Requirements - 624 Mobilization. 868

625 Highway Lighting.. 869

General 625.01. 869

Materials (625.05) 870

Working Drawings (625.06) 871

Luminaires (625.08) 872

Luminaire Supports (625.09) 874

Foundations (625.10) 877

Junction Boxes (Handholes) & Pull Boxes (Manholes) (625.11) 879

Raceways and Conduits (625.12) 879

Trenching (625.13) 879

Power Service (625.15) 880

Grounding (625.16) 880

Wiring and Cabling (625.17) 882

Connections (625.18) 884

Testing of Installation (625.19) 886

Information to Maintaining Agency. 887

Documentation Requirements. 887

626 Barrier Reflectors. 889

General 889

Materials (626.02) 889

Installation (626.04) 889

Documentation Requirements - 626 Barrier Reflectors. 890

630 Traffic Signs and Sign Supports. 891

Description (630.01) 891

Sign Fabrication (630.04) 892

Foundations (630.05) 893

Sign Supports (630.06) 895

Sign Erection (630.07) 911

Sign Shipment and Storage (630.08) 913

Sign Inspection (630.13) 914

Documentation Requirements – 630 Traffic Signs and Sign Supports. 914

631 Sign Lighting and Electrical Signs. 915

General (631.02) 915

Inspection and Testing (631.11) 917

Documentation Requirements – 631 Sign Lighting and Electrical Signs. 917

632 Traffic Signals and 633 Signal Controllers. 919

General 919

Foundations (632.14) 919

Electrical Appurtenances. 919

Pole and Support Inspection - General 922

Signal Support (632.15) and Strain Pole (632.16) 922

Cable Support Assemblies (632.21) 924

Messenger Wire (632.22) 927

Preformed Guy Grips. 929

Cable and Wire (632.23) 931

Power Service (632.24) 933

Signal Equipment and Wiring. 934

Testing (632.28) 943

Documentation Requirements - 632 Traffic Signal Equipment 947

Documentation Requirements - 633 Traffic Signal Controllers. 948

632/633 Supplemental Information. 949

638 Water Mains and Service Branches. 967

Documentation Requirements - 638 Water Mains and Service Branches. 967

640 Pavement Markings. 968

641 Pavement Markings – General.. 968

Pavement Marking Materials (641.02) 968

Application of Pavement Marking Materials (641.03) 968

Data Logging System (DLS) (641.04) 968

Construction Inspection during Pavement Marking Installation. 988

642 Traffic Paint.. 992

Documentation Requirements - 642 Traffic Paint 992

643 Polyester Pavement Marking.. 993

Documentation Requirements - 643 Polyester Pavement Marking. 993

644 Thermoplastic Pavement Marking.. 994

Documentation Requirements - 644 Thermoplastic Pavement Marking. 994

645 Preformed Pavement Marking.. 995

Documentation Requirements - 645 Preformed Pavement Marking. 995

646 Epoxy Pavement Marking.. 996

Documentation Requirements - 646 Epoxy Pavement Marking. 996

647 Heat-Fused Preformed Thermoplastic Pavement Marking.. 997

Documentation Requirements - 647 Heat Fused Preformed Plastic Pavement Marking  997

648 Spray Thermoplastic Pavement Marking.. 998

Documentation Requirements - 648 Spray Thermoplastic Pavement Marking. 998

650 Roadsides. 999

651 Topsoil Stockpiled.. 999

652 Placing Stockpiled Topsoil and 653 Topsoil Furnished and Placed   1000

Documentation Requirements - 652 Placing Stockpiled Topsoil and 653 Topsoil Furnished and Placed  1000

654 Renovating Existing Soil.. 1001

656 Roadside Cleanup. 1002

Documentation Requirements - 656 Roadside Cleanup. 1002

657 Riprap for Tree Protection.. 1003

Documentation Requirements - 657 Riprap for Tree Protection. 1003

658 Tree Root Aeration.. 1004

Documentation Requirements - 658 Tree Root Aeration. 1004

659 Seeding and Mulching.. 1005

Documentation Requirements - 659 Seeding and Mulching. 1005

660 Sodding.. 1006

Documentation Requirements - 660 Sodding. 1006

661 Planting Trees, Shrubs, and Vines. 1007

Description (661.01) 1007

Labeling (661.05) 1007

Acceptance (661.06) 1007

Planting (661.10) 1012

Wrapping, and Bracing (661.12 and 661.13) 1013

Period of Establishment (661.14) 1017

Plant Substitution List 1019

Method of Measurement and Basis of Payment (661.17 and 661.18) 1019

661 Appendix I – Shade Trees. 1020

661 Appendix II - Deciduous Shrubs. 1021

661 Appendix III - Coniferous Evergreens. 1021

661 Appendix IV - Broadleaf Evergreens. 1023

662 Landscape Watering.. 1025

General 1025

Documentation Requirements - 662 Landscape Watering. 1025

666 Pruning Existing Trees. 1026

Documentation Requirements - 666 Pruning Existing Trees. 1026

670 Erosion Protection.. 1027

Documentation Requirements - 670 Erosion Protection. 1027

671 Erosion Control Mats. 1028

Documentation Requirements - 671 Erosion Control Mats. 1028

SS 832 Temporary Sediment and Erosion Controls. 1029

Description (832.01) 1029

Definitions (832.02) 1029

Standard Construction Drawing Reference (832.03) 1029

Requirements (832.04) 1030

Provisions (832.05) 1030

EDA Requirements (832.06) 1030

BMP Materials (832.07) 1031

Furnish and Locate BMP (832.08) 1032

Storm Water Pollution Prevention Plan (SS 832.12) 1046

Documentation Requirements – SS 832 Temporary Sediment and Erosion Controls. 1048

SS-840 Mechanically Stabilized Earth (MSE) Walls. 1050

Introduction. 1050

General Information. 1052

Terms. 1053

Construction (840.06) 1055

Panel Inspection. 1068

Final Checks. 1118

MSE Wall Construction Do’s and Don’ts. 1121

Out of Tolerances Conditions and Possible Causes Criteria. 1122

Documentation Requirements – 840 MSE Walls. 1123

850 Cement Treated Free Draining Base.. 1125

Materials (850.02) 1125

Proportioning, Mixing, and Transporting (850.03) 1125

Verification of Design (850.04) 1125

Equipment (850.05) 1125

Placing and Spreading (850.06) 1127

Limitations on Placing Operations (850.07) 1127

Compaction and Shaping (850.08) 1128

Curing (850.09) 1129

Protection of the Underdrains (850.10) 1129

Protection of the Cement Treated Free Draining Base (850.11) 1129

Thickness Tolerances (850.12) 1130

Surface Tolerance (850.13) 1130

Exposure to the Elements (850.14) 1130

Method of Measurement and Basis of Payment (850.15 & 850.16) 1130

Documentation Requirements - 850 Cement Treated Free Draining Base. 1130

851 Asphalt Treated Free Draining Base.. 1132

Description (851.01) 1132

Materials & Composition (851.02 & 851.03) 1132

Design Verification (851.04) 1132

Rollers (851.06) 1132

Weather Limitations (851.07) 1133

Spreading and Compacting (851.08) 1133

Thickness Tolerances (851.09) 1133

Surface Tolerance (851.10) 1134

Quality Control and Acceptance (851.11) 1134

Underdrains (851.12) 1134

Protection of the ATFDB (851.13) 1134

Exposure to the Elements (851.14) 1135

Method of Measurement and Basis of Payment (851.15 and 851.16) 1135

Documentation Requirements - 851 Asphalt Treated Free Draining Base. 1135

S-1015 Compaction Testing of Unbound Materials. 1136

General 1136

Metrication and Rounding. 1137

Importance of Proper Inspection and Compaction Testing. 1137

Compaction of Soils. 1138

Compaction Testing of Soils (1015.06) 1152

Compaction Testing Requiring an Aggregate Correction (1015.06.C.2) 1170

Compaction Testing for Granular Materials (1015.06.C.1) 1180

Procedure for Constructing a Test Section Method A (1015.06.C.3) 1185

Test Section Method B (1015.06.C.3) 1186

Test Section Method C (1015.06.C.3) 1188

Compaction Testing for Shale (1015.07) 1189

Compaction Acceptance (1015.08) 1189

Number of Tests (1015.09) 1189

Documentation Requirements - Supplement 1015 Compaction Testing of Unbound Materials  1190

Foreword

This manual provides highway construction personnel with relevant, practical information in order to administer construction, perform accurate inspections, and provide relevant construction procedural information for the various roadway and structures items of work.  It is the responsibility and duty of all Department personnel involved in highway construction to become familiar with the content and intent of this manual.

This manual includes background information for select items of work.  This information is intended to assist construction personnel with understanding and solving various field problems and issues.  The examples and graphics contained in this document are intended to provide guidance for a practical approach to inspection and construction processes and procedures.  This manual is not intended to be a complete, all inclusive text detailing every aspect of highway construction, but rather an operational guidebook for highway construction and inspection techniques.

In order to take complete advantage of the information in the manual, project personnel should have a comprehensive understanding of the Construction and Material Specifications, Supplemental Specifications, Standard Drawings, and other pertinent contract documents.  Unless specifically incorporated by reference into the contract documents, this manual is not contractually binding on either contracting party.  The information contained in the manual does not replace, supersede, or otherwise modify any specification, plan, or proposal provision, or other contract document or condition except as noted.

As the on-site representatives of the Department, ODOT Inspectors and Engineers are authorized to observe all work being performed to ensure compliance with the contract.  As the required inspection activity occurs, the Department has an obligation to inform the Contractor on a regular basis regarding the quality and compliance of the work performed.  Conversely, the Contractor also shares in the responsibility to provide information regarding construction problems or issues to the Department for timely resolution consistent with joint issue mitigation responsibilities (C&MS 108.02.F).

The primary goal of this manual is to present functional highway construction information in order to provide practical guidance to personnel involved in this effort.  The Department is responsible for monitoring and documenting construction activity in the project diary to ensure the intent of the contract is reflected in the final product delivered to the Department.  Secondly, timely and proper inspections are critical to ensure an acceptable level of project quality.  For these reasons, this manual has been developed to assist in ensuring that correct, accurate, and thorough administration and inspections of the work are performed consistently statewide.

Introduction to Construction Administration and Inspection

This manual provides construction personnel with information to effectively administer the project and to perform accurate inspections and documentation of the construction work items.  It is the duty of ODOT Project Engineers and Inspectors to become familiar with the contents of this manual.

Included in this manual is background information for the specific items of work.  This background information will help construction personnel understand various field problems and associated solutions.  Examples, problems and figures are provided as guidance throughout this manual.

This manual should not be considered a complete textbook detailing all aspects of construction.  In order to completely take advantage of the information in this manual, project personnel should be familiar with the Construction and Material Specifications, Standard Drawings, and other contract documents.

Unless specifically referenced in the contract, this manual is not a part of the contract with the Contractor.  The information contained in the manual does not replace, supersede, or modify any specification, plan, or proposal provisions of the contract.

As the representatives of the Department, ODOT Inspectors and Engineers observe the Contractors’ work to ensure compliance with the specifications.  Correct and accurate inspections are critical tools to ensure the quality of the work.  As ODOT inspects the work, Inspectors and Engineers document progress and communicate with the Contractor daily about the quality and compliance of the work.

When work is deficient or defective, many times the Department suffers significant financial losses due to one of the following reasons:

·         The instructions to the Contractor were in error or did not occur.

·         The Department testing was performed incorrectly.

·         Inspection forms or details are incomplete or conflicting.

·         No inspection occurred during the construction of the item.

All of the above are arguments that the Contractor could raise when asserting a claim.  Valid or not, these are reasons that will be debated when responsibility is discussed. 

Our goal is to minimize the Department’s responsibility in claim situations and maximize the quality of the work performed.  The Department needs to correctly monitor the construction activities and document those activities in the project diary to ensure the contract intent is carried through during the construction.  

General Documentation Requirements

Project Records

The Project Engineer or Inspector must set up a records system to adequately record the daily activities on the project.  These records should include the following, as applicable:

·         A folder for each reference number

·         Proposals / addendum folder

·         A folder for each change order

·         Supplemental specifications

·         TE-30 Material Inspection Reports

·         TE-45 Daily Concrete Reports

·         TE-31 Material Inspection Reports

·         TE-24 Material Certification Reports

·         Partnering file

·         Pre-construction and other Meeting notes

·         C-95 issues folder

·         Change order items pending

·         Issue folders (claims, etc.) / Waste Borrow Agreements

·         Correspondence from Contractor

·         Correspondence from others

·         ODOT correspondence to Contractor

·         ODOT correspondence to others

·         Delivered materials

·         CA-EW-5 compaction tests

·         Grade checks

·         Contractor storm sediment and erosion control checklist

·         Survey notes

·         Utility folders

·         Railroad folders

·         Estimate folder

·         CA-D-3 and CA-D-4 folders

·         C-92 / Payroll / Labor compliance forms

·         Schedule folder

·         MOT review folder

·         Value Engineering Proposals (VECP) File

General Guidelines for Documentation

Documentation consists of the written project records necessary to verify performance of the work item. Documentation is continuous and must be coordinated with the construction progress.

To meet the requirements for payment on Federal-Aid and state projects, the following two conditions must be met:

·         The final quantity has been determined in accordance with the specifications and the necessary weight tickets, measurements, calculations, etc. are validated properly. Procedures for meeting these conditions are contained in this handbook.

·         The work has been completed in substantial conformity with the plans and specifications, and this fact is documented and placed in the project files.

Procedures for meeting these conditions are contained in the referenced construction procedures handbooks and manuals.

As a rule, the Inspector's reports or related forms should contain information in sufficient detail to verify that construction is in substantial conformity with the plans and specifications.

Documentation shall be validated in every case with the following seven identifiers:

·         Date

·         Project Number

·         Item Number

·         Reference Number

·         Subject

·         Location

·         Signature or Initials

As items of work are completed by the Contractor, project inspectors are required to document the work as previously discussed.  Accepted quantities will be turned in for payment on the Daily Diary under the area entitled, "Pay Items," listing the reference number, extra work number if applicable, participation code, description of work, location, and quantity or lump sum amount.  It must be emphasized that all items turned in for payment must be supported by documentation kept in the project files under the appropriate contract reference number.

Substantiation

This manual describes in detail the requirements of documenting substantial conformity with contract requirements.  Substantiation includes the usage of specific forms and documentation of measurements and testing methods. Progressive project inspection and control records must be related to items being documented so that they readily substantiate and verify that documented quantities are placed in accordance with contract requirements.  These records are to be placed in the project file each day.

For the purpose of documentation, project records must be identified with the seven identifiers listed above.  These records must also show location data, include computations, and be filed in the project records.  Records will be on designated forms identified within this manual.

Measurement

Individual measurements will be made with sufficient accuracy and frequency to avoid unrealistic accumulations. The summary of final pay quantity is rounded off to the units shown in the proposal.  Include the seven identifiers listed above with a documentation record of each pay item on a designated form and file in the project records.

Sketches

Photos, video, sketches, and drawings may be used wherever they can aid in clarifying locations or dimensions.

Validation

The seven identifiers listed above must be included on tickets and tapes if no other documentation forms are used for the item. If separate forms are used (e.g., asphalt tickets used along with the Bituminous Concrete Inspection Form), initials should be on the tickets, and the seven identifiers are required on the form.

The printed weight ticket from automatic or semiautomatic scale operations is acceptable documentation.  Should material be delivered to the project without a verifiable weight ticket from the source, due to infrequent use or oversight, the material may be re-weighed or weight may be checked by comparison to measured volume in place.  Action taken will be recorded on the ticket.

Items paid for on a unit, lump sum, length, area, volume, or miscellaneous basis, either in place or from verified plan dimensions, will be validated by the initials of the person making or verifying measurements, calculations, and observations.

Where partial loads are involved, quantities will be determined from measurements in the vehicle or calibrated tanks.

Filing

All printed project records must be maintained in the field office in a file by project number.  Tickets and other bulky items may be filed separate provided they are referenced to the associated contract reference number.  Upon completion of the project, the entire file will be moved to the District Office and maintained for future reference.  All final quantity documentation will be delivered to the District Office in a timely manner at the discretion of the District Documentation Coordinator after completion of the physical work.  District project files will be maintained in a single, well-organized location for the time period outlined in the ODOT record retention schedule.

List of Forms

The following forms are called out in this manual.  The District may modify the forms ONLY if the modified forms contain all of the information listed on the standard forms.  Forms may be found online at the following website:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Admin/Pages/Documentation.aspx

Forms are also available in the Construction Inspection Forms Booklet.

CA-C-1

Concrete Control Test Form

CA-C-2

QC/QA Concrete QCP Checklist

TE-45

Concrete Inspectors Daily Report

CA-D-1A   

Field Calculation and Measurement

CA-D-1B   

Field Calculation and Measurement

CA-D-2

Field Calculation and Measurement

CA-D-3SM  

ODOT Inspectors Daily Report

CA-D-4SM

ODOT P.E. / P.S. Daily Report

CA-D-5

Daily Account of Force Account Work

CA-D-6

Pavement Repair and Sawing Measurement

CA-D-7

Short Term Work Zone Review

CA-D-8

Worksite Traffic Supervisor (WTS) Daily Inspection Report- 1/2, 2/2

CA-D-10

Contractor Signature Authorization

CA-D-11

Contractor Payment Certification

CA-D-12

Contractor Final Certification

CA-EC-1     

Weekly and Rain Event Checklist

CA-EC-2    

Seeding Calculations

CA-EW-1

Earthwork Quantity Calculations

CA-EW-2

Proof Rolling Documentation

CA-EW-3

Log of Test Pit Investigation

CA-EW-4

Moisture Density Curve Calculation

CA-EW-5

Nuclear Gauge Compaction Form

CA-EW-6

Nuclear Gauge Compaction with Aggregate Correction

CA-EW-7

Non-Stabilized Drainage Base Compaction

CA-EW-8   

Authorization of Undercuts

Typical Moisture Density Curves - Set C - May, 1949

Zero Air Voids Graph

CA-EW-9  

Rock Blasting Inspection Form

CA-EW-10   

Rock Blasting Drilling Log

CA-EW-11   

Blast Site Security Plan

CA-EW-12   

Daily Earthwork Inspection Form

CA-FP-1    

Warranty Asphalt Checklist

CA-FP-2     

Random Selection of Asphalt Field Samples (448, 403)

CA-FP-3    

Summary of Asphalt Concrete Quantities

CA-FP-4    

Asphalt Concrete Inspection

CA-FP-5    

Roller Capacity and Placement Rate Inspection Form

CA-FP-6    

Calculation of Liquid Asphalt Materials

CA-L-1

Report of Electrical Tests

CA-L-2

Report of Electrical Tests

CA-L-3

Report of Electrical Tests

CA-L-4

Report on Sign Lighting

CA-L-5

Report on High Voltage Direct Current Tests

CA-P-1

Pipe Construction Inspection Form - 1/2, 2/2

CA-P-2

Underdrain Construction Inspection Form 1/2, 2/2

CA-P-3

Drainage Structure Inspection Form 1/2, 2/2

CA-S-1

Inspection Record for Drilled Shafts

CA-S-2

Paint Thickness, QCP #5, #8, #10

CA-S-3

(BR-2-75) Pile Driving Log

CA-S-4

High Performance Concrete Pre-Pour Meeting  - 1/3, 2/3, 3/3

CA-S-5

Micro-Silica Overlay Pre-Pour Meeting - 1/3, 2/3, 3/3

CA-S-6

Class S or QC-2 Concrete Pre-Pour Meeting  - 1/2, 2/2

CA-S-7

QCS Inspection Documentation

CA-S-8

(BR-5) Piling Measurement Record

CA-S-11

QCS & Visual Standards Information

CA-S-12

Bridge Painting Quality Control Points (QCP #1 & #2)

CA-S-13

Abrasive Blasting (QCP#3)

CA-S-14

Disposal of Hazardous / Non-Hazardous Waste for Bridge Painting (QCP#4)

CA-S-15

Prime Coat Application (QCP#5)

CA-S-16

Bridge Painting Grinding Fins, Tears, Slivers and Caulking, (QCP #6 & #9)

CA-S-17

Intermediate & Finish Coat Application (QCP #8 & #10)

CA-S-18

Bridge Painting Destructive Test Log (QCP #11)

CA-S-19

Bridge Painting Final Review (QCP #11)

CA-S-20

Erection (Demolition) Procedure Checklist

CA-S-21

Sealing of Concrete Surfaces Checklist

CA-S-22

Bridge Deck Concrete Placement Dry Run Form (Outline)

CA-S-30

(D10-S-30) Reinforcing Steel Verification

CA-S-31

(D10-S-31) Air Tests for Superstructures

CA-S-32

(D10-S-32) Structure Temperature Record

CA-T-1

DLS Report Format - Weight-Based System

CA-T-2

DLS Short Report Format - Weight-Based System

CA-T-3

DLS Report Format - Stroke Counter System

CA-T-4

DLS Short Report Format - Stroke Counter System

CA-T-5

DLS Report Format - Flow Meter-Based System

CA-T-6

DLS Short Report Format - Flow Meter-Based System

CA-T-7

DLS Report Format - Thermoplastic System

CA-T-8

DLS Short Report Format - Thermoplastic System

C-85 Letter

Sample Final Estimate Letter

C-85 Final

Report of Final Inspection

C-85 LPA

Report of LPA Final Inspection

C-85 Partial

Report of Partial Inspection

C-85 Punchlist

Report of Punch List Completion

TE-31

Sample Data

TE-217

Bituminous Concrete Density Determination – 446 Cores

Daily Concrete Pavement Documentation Form

101 Definitions and Terms

General

Common words and terms used in this manual are defined in this section.  Definitions for other words or terms that may call for clarification in this manual are found in the “Construction and Material Specifications.”

AASHTO - American Association of State Highway and Transportation Officials.

ACFA - Actual Cost of Force Account.

ASTM - American Society of Testing and Materials.

Blue Book - Rental Rate Blue Book for Construction Equipment.

C&MS - The Construction and Material Specifications of the Ohio Department of Transportation.

Calendar Day - Everyday shown on the calendar.

Change Order - A written order issued by the Department to the Contractor, covering changes to contract terms and conditions, plans and/or quantities, within or beyond the scope of the Contract and establishing the basis of payment and time adjustment for the work affected by the changes.

Completion Date - The date, as shown in the contract documents, on which the work contemplated, shall be completed.

Construction Monitor - The DCA appointed ODOT employee responsible for primary construction administration coordination with the LPA and its designated employees, engineers, and contractors on Local let projects.

Contract Limits - The amount a contract pay item may be increased or the cost of a new item of work that may be added to a project without competitive bidding or Controlling Board review.  ORC 5525.14 sets these limits as:

                Original Contract Price                            Contract Limits

                $500,000 or lower                                   $25,000

                $500,001 to $2,000,000                          5% of Total Contract Price

                Over $2,000,000                                     $100,000

Contractor - The individual, firm, or corporation contracting with the Ohio Department of Transportation for the performance of prescribed work acting directly or through a duly authorized representative and qualified under provisions of the law.  Defined in C&MS 101.03.

Conversion - The adaptation of one unit of measure to another unit of measure.

CPM Schedule - The type of progress schedule outlined in Proposal Note 107 that delineates a critical path of work from the start of the project to the end of the project.

Critical Path - The critical path is defined as the longest path of activities in the project that determines the project completion date. The activities that make-up the critical path of activities are the “Critical Activities.”

DCA -District Construction Administrator.

DDD - District Deputy Director.

Density - The relation of weight to volume. The greater the weight to a given volume, the greater the density.

Department - The Ohio Department of Transportation.

Director - The Director of the Department of Transportation, the Executive head of the Department of Transportation, appointed by the Governor.

Documentation - Recording and filing evidence that the material or work is in conformance with specifications and in the amounts required.

ECFA - Estimated Cost of Force Account.

Elevation - The height as measured from a predetermined point denoted in the plans.

Engineer - The person representing the Department who is charged with the overall responsibility at the project site for seeing that construction is in conformance with plans and specifications and that all checks for job control and validation of pay items are documented and filed properly.

Engineer’s Punch List - Written list, by the Project Engineer or Project Supervisor (P.E./P.S.) of items not yet completed by the Contractor and corrective work.

Estimate - The District authorization of monetary payment compensating the Contractor for work in place or stored materials following Contractor certification to the Engineer that the work for which the progress payment is being made was performed in accordance with the contract.

EWCO - Extra Work Change Order.

Extra Work -   1. An increase in a bid item quantity for payment beyond Contract Limits.

                          2.  A new pay item.

FHWA – The Federal Highway Administration, a section of the U.S. Department of Transportation.

File - The complete project file in the field office in which is placed all progress records and documentation of pay items.

Final Estimate - The District authorization of monetary payment compensating the Contractor to the final value of the contract following the final inspection and acceptance of the project in accordance with current policies. The Final Estimate is signed by the District Construction Administrator.

Final Inspection Date - The date the Final Inspector physically inspects the project. This date is entered into SiteManager KETRK (Keycode 155).

Final Inspection Punch List - Written list, by the Final Inspector, of deficiencies found during the Final Inspection.

Final Inspector - The Professional Engineer with construction experience appointed by the DDD to perform Final Inspections. See part I. of this procedure and C&MS Section 101.03. This term includes the Final Inspector’s Back-up.

Final Measurements - A legal term used in ORC 5525.14 which means an increase in an original bid  item that was required to accomplish the originally planned work within the original work limits, but resulted in a payment on the bid item that exceeded the Contract Limits.  Change orders for Final Measurements are not subject to Controlling Board approval, but must be reported quarterly to the Controlling Board.  Final Measurements are not limited to pay quantities determined during finalization, but may occur any time during the project.

Final Package - Information submitted by the District to Central Office Capital Accounting that includes the transmittal IOC, Final Estimate, Final Report, and Summation of Extra Work Items.

Final Payment - The payment that is released when all the requirements of C&MS Section 109.12 have been fulfilled and the FHWA final voucher is issued.

Final Report - The document submitted by the District to Central Office Capital Accounting documenting the modifications to the original contract amount and certified by the District Construction Administrator and District Deputy Director.

Force Account - Payment for work directed by the Engineer based on the actual cost of labor, equipment, materials furnished, overhead, and profit in accordance with C&MS Section 109.05.

Inspection - Examination by observation, measurement, or tests to determine that materials and work are in conformance with specifications.

Inspector’s Daily Report - A form used by an inspector to document the activities performed by a Contractor.  The Inspector Daily Report is Form CMS-1, CA-D-3A or CA-D-3B.

Interim Completion Date - The date, as shown in the Contract Documents, on which a portion of the work contemplated, shall be completed.

Laboratory (Laboratory with “L” capitalized) - The Office of Materials Management of the Department of Transportation, 1600 West Broad Street, Columbus, Ohio 43223.  If reference is to the District laboratory, it is so designated.

Lane or Traffic Lane - A strip of pavement of specified width, usually 12 feet (3.6 m).

Lien - A Public Improvement Lien [ORC Section 1311.25]; the right to withhold payment from the Contractor as security for a debt to a material supplier, laborer, or subcontractor.

Local Public Agency (LPA) - Any other state agency, local political subdivision, board, commission, or other governmental entity identified under the Ohio Revised Code Section 5501.03, Paragraph C as being eligible for assuming the administrative responsibilities for Department improvement projects known as LPA or Local Let projects.

MOP - Construction Inspection Manual of Procedures.

NHS - National Highway System. The system of roadways so designated by the National Highway Systems Act of 1995. 

OAC - Ohio Administrative Code.

ORC - Ohio Revised Code.

P.E./P.S. - Project Engineer or Project Supervisor performing the duties of the Engineer as defined in C&MS 101.03.

P.E./P.S. Daily Report - A form used by the Engineer or Project supervisor to document the activities performed by a Contractor.  The P.E./P.S. Daily Report is Form CMS-2, CA-D-4.

Pay Item - A specifically described unit of work for which a price is provided in the contract.

Physical Work Complete Date - Last day of work by the Contractor, including work to complete the Final Inspector’s Punch List.  If there were no Punch List items, then this date is the same as the Final Inspection Requested Date.  This date is entered into SiteManager KETRK (Keycode 160).

Plans - The plans, profiles, typical cross-sections, working drawings and supplemental drawings, approved by the Director, or exact reproductions thereof, which show the location, character, dimensions, and details of the work.

Progress Samples - Samples taken by Laboratory or project personnel not engauged in job control sampling. Samples are obtained at random from materials delivered for incorporation in the work to provide an independent spot check on the reliability of the results obtained in job control sampling and testing.

Project - The specific section of the highway together with all appurtenances and construction to be performed thereon under the contract.

Project Engineer - Also called the Engineer. The person representing the Department who is charged with the overall responsibility at the project site for seeing that construction is in conformance with plans and specifications and that all checks for job control and validation of pay items are documented and filed properly.

Project Limits - Project limits are points on the mainline centerline of construction where the proposed improvement, as described in the project description on the title sheet of the plans (excluding incidental construction), begins and ends.  Incidental construction includes all work required to complete a project in addition to the primary purpose for the improvement.

Proposal - The offer of a bidder, on the prescribed form properly signed and guaranteed, to perform the work and to finish the labor and materials at the prices quoted.

PWC - Physical Work Completed.

Requested Date - The date the work is completed to the satisfaction of the P.E./P.S. and is ready for Final Inspection. This date is entered into SiteManager KETRK (Keycode 150).

RFI - Request for Information.

RWCO - Regular Work Change Order.

SiteManager - The Department-wide computer system for administration of construction projects.

Specifications - The directions, provisions and requirements contained in the State of Ohio, Department of Transportation Construction and Material Specifications as supplemented by the supplemental specifications and special provisions.

Standard Drawings - The Standard Construction Drawings issued by the Bureaus of Location and Design, Bridges and Design Services.

State Final Acceptance Date - The date of the Final Estimate Letter to the Contractor. This date represents that the requirements of ORC 5525.16, CFR 23 part 635, and C&MS 109.12 have been met. This date is entered into SiteManager KETRK (Keycode 370).

TAS - Testing Administration System, a part of SiteManager which provides support to all sampling, testing, and approval or disapproval of materials used on a project, to the time at which the contract has been finalized.

Time Extensions - Change in the contract provision that stipulates the date by which the work must be complete.  (Previously known as Postponement of Contract Completion Dates).

Tolerance - The allowable limits of variation from a specified measurement.

Transition - The distance in which a change is made gradually from one pavement cross-section to another.

Verification - The steps necessary to determine that the work or materials described are in conformance with plans and specifications.

Workday - A calendar day that the Contractor normally works.

Flexible Pavement Terms

Aggregate - Mineral material, such as sand, gravel, crushed stone, slag, or combinations hereof.

Asphalt Concrete - A mixture of aggregate and asphalt binder.  Types of asphalt concrete are 301, 302, 442, 446, and 448.

Batch Plant - A plant in which dry, hot aggregate and asphalt material are proportioned in fixed or batched quantities into a pugmill (mixer) for mixing.  Then the resulting asphalt concrete is either batched directly into a haul truck or stored in a storage bin for later use.

Asphalt Concrete Base - A type of asphalt concrete which is used as a base course in the construction of a pavement.  Two types of asphalt concrete base are 301 and 302.

Asphalt Binder- A thermoplastic binding material obtained as a residue in the distillation of petroleum, which may contain additives to enhance performance.

Bleeding - The rising of an excess of asphalt material to the surface of an asphalt concrete mixture.

Checking - Short transverse cracks, 1 to 4 inches (25 to 100 mm ) in length and 1 to 3 inches (25 to 75 mm) apart, which develop in the surface of the asphalt concrete mat during the compaction process.

Choke - Aggregate used for the purpose of filling the surface voids of a coarse aggregate mixture.

CMS - Cationic medium setting emulsion.  See the definition for emulsion.

Coarse Aggregate - Aggregate which is retained on the No. 4 (4.75 mm) sieve.

Compaction - A consolidation or compression of materials resulting in an increase in density of the materials.

Compression Rolls - The compaction load of a steel wheel roller, expressed in pounds per inch (kN/m), which is defined as the weight of the roller divided by the combined width of all the drums on the roller.  The compression rolls requirements for rollers are specified in 401.13.

Course - A layer or layers of a given material or mixture placed as a part of the pavement structure.

Cross-Section - In the field, elevations taken along a line at right angles to the centerline.  On a drawing, a profile of the existing ground at right angles to the centerline.  The drawing of an earthwork cross-section also shows the shape of the finished excavation or embankment at the same point.  A roadway cross-section shows the thickness and width of the pavement courses.

Cross-Slope - The transverse slope of the pavement, either crown or superelevation.  See section 401.19 for details on checking the cross-slope of a pavement.

Crown - The height of the center of the roadway surface above a straight line drawn between its edges.  See section 401.19 for details on checking the crown of a pavement.

Cut Back Asphalt - Asphalt binder which has been rendered fluid by fluxing it with a light volatile petroleum distillate.  Upon exposure to atmospheric conditions, the volatile distillate evaporates, leaving only the asphalt cement which reverts to its original semi-solid condition.  Cut back asphalts are classified as rapid curing (RC), medium curing (MC), or slow curing (SC).

Degradation - A reduction in aggregate particle size due to breakage and water.

Density - The ratio of the weight of a given material to its volume.

Drum Mix Plant - A continuous production plant in which cold aggregate is proportioned and dried in the first half of a drum and then mixed with bituminous material in the second half of the drum.  Then the resulting asphalt concrete is stored in a storage bin for later use.

Emulsion (Asphalt) - A suspension of extremely small droplets of asphalt in water in the presence of an emulsifying agent, which usually is a type of soap.  Upon exposure to atmospheric conditions, the water evaporates, leaving only the asphalt cement which has been modified by the emulsifying agent.  Emulsions are classified as rapid setting (RS or CRS), medium setting (MS or CMS), or slow setting (SS or CSS).  The letter “C” in front of an emulsion type (CRS, CMS, or CSS) denotes a cationic (positively charged) emulsion.  If the emulsion type does not start with the letter “C” (RS, MS, or SS), the emulsion is anionic (negatively charged) or non-ionic (neutral charge).  If the emulsion type is followed by an “h” (SS-1h, CMS-2h, etc.), the emulsion was made from a harder base asphalt cement.

Fat Spots - See the definition of bleeding.

Fine Aggregate - Aggregate which passes the No. 4 (4.75 mm) sieve.

Flushing - The drawing of asphalt material to the surface of an asphalt mixture due to the action of traffic.

Gradation - The distribution of particle sizes in an aggregate or asphalt mixture.

Grade - The rate of change of the profile elevations.  See section 401.19 for details on checking the grade of a pavement.

JMF - See the definition of job mix formula.

Job Control - Inspection and testing conducted to determine compliance of the materials and work with the contract requirements.

Job Mix Formula - The mix composition of an asphalt concrete approved by the Laboratory.  The job mix formula (JMF) of a mix can be obtained from the “BCJMF” screen in the TAS portion of SiteManager.  The JMF number of the mix needs to be known to use the “BCJMF” screen.

Keying - The interlocking of aggregate particles by compaction.

Laboratory - The Office of Materials Management of the Department’s Central Office in Columbus, which is also known as the Central Test Lab.

Marshall Mix Design - Volumetric mix design procedure used to establish the optimum asphalt binder content for an asphalt concrete.  The procedures for designing a mix using the Marshall mix design are contained in 441.02 and the Asphalt Institute Manual Series No. 2.

Mineral Filler - Limestone dust, Portland cement, or other inert mineral matter.  The specifications for mineral filler are contained in 703.07.

NAPA - National Asphalt Pavement Association.

NCAT - National Center for Asphalt Technology.

Odometer - An instrument used for measuring traveled distance.

Oscillating Wheel - The vertical movement of pneumatic tire roller’s wheels over irregularities in the surface on which the roller is operated, providing a kneading action.

PG (Asphalt) Binder - An asphalt binder which has been graded by the PG Binder system.  An asphalt binder has to be modified with an additive to meet some of the PG Binder grades.  An example of a PG Binder Grade is PG 64-28.  An example of a modified PG Binder Grade is PG 70-22M (See Asphalt Binder).

Placement Rate - The placement of paving materials on the basis of a given weight and area covered.  Placement rate is described in detail in section 401.21.

Plant - The plant where aggregate and asphalt material are mixed together or the plant which produces the aggregate or the asphalt material.

Pneumatic Tire Roller - A roller with three to five rubber tires mounted on two tandem axles.  The wheels that the tires are mounted to oscillate, which means they are capable of moving up and down independently of each other.  The pneumatic roller compacts a pavement using the combined force of weight and the kneading action of the oscillating wheels.  The specifications for a pneumatic tire roller are contained in 401.13.

Prime Coat - An application of asphalt material made on the surface of a pavement layer for the purpose of binding the surface particles together.  The specifications for a prime coat are contained in 408.

Profile - A line on a drawing which shows elevation of points along a selected route.  A profile usually shows both ground elevations and grade-line elevations.  See Section 401.19 for details on checking the profile of a pavement.

RAP - The abbreviation for reclaimed asphalt pavement, which comes from reclaimed asphalt concrete pavement.  The specifications for the use of RAP is contained in 401.04 and 441.03.

Raveling - The loss of aggregate from the surface of an asphalt mixture due to a lack of adequate compaction, segregation of the mixture, moisture damage, high dust content, or a lack of PG binder for binding the aggregate particles together.

Screed - A rectangular trowel on an asphalt paver used to cut off the asphalt mixture at the desired thickness, to smooth the surface, and consolidate the material.

Screenings - This is No. 10 size gravel, stone, or air-cooled slag.  The specifications for screenings are contained in 703.10.

Segregation - The separation of the coarse and fine particle sizes in an aggregate or asphalt mixture.

Shoving - The plastic deformation or displacement in an asphalt mixture in the direction of traffic movement.

Steel Wheel Roller - A roller which compacts asphalt concrete with static steel drums.  Types of steel wheel rollers are the three-wheel roller, tandem roller, trench roller, and vibratory roller.

Strike Off - A blade used to cut off material at the desired elevation or thickness.

Superelevation - The difference in elevation between the inside and outside edges of a roadway on a horizontal curve.  See section 401.19 for details on checking the superelevation of a pavement.

Superpave - Mix design procedure, which establishes material properties of an asphalt concrete mix by using a gyratory compactor and material requirements.

Surface Texture - A term used to describe the appearance of the surface of a pavement course such as sandy, coarse, open, dense, uniform, etc.

Surface Treatment - See the definitions for chip seal, prime coat, or tack coat.

Tachometer - An instrument for measuring the speed of rotation.

Tack Coat - An application of asphalt material made on a pavement surface for the purpose of bonding the existing course to the overlying course.  The specifications for a tack coat are contained in 407.  Tack coats are described in Section 6.

Tandem Roller - A steel wheel roller with two drums mounted on tandem axles, which compacts a pavement using the force of the roller’s weight.  The specifications for a tandem roller are contained in 401.13.

Three-Wheel Roller - A steel wheel roller with three drums, two drums mounted on the rear axle and a smaller drum mounted on the front tandem axle, which compacts a pavement using the force of the roller’s weight.  The configuration of the drums on a three-wheel roller allows it to compact longitudinal joints without interfering with traffic in the adjacent lane.  The specifications for a three-wheel roller are contained in 401.13.

Vibratory Roller - A steel wheel roller with one (single drum) or two (double drum) drums, which compacts a pavement using the combined force of weight and the vibration of the drum or drums.  The specifications for a vibratory roller are contained in 401.13.

Viscosity - Resistance to flow in a liquid.  The higher the viscosity, the greater the resistance to flow.

Yield - The area of a surface covered by a given quantity of material measured in square yards (square meters).

Concrete Terms

Absorption - The soaking up of moisture (water) by aggregate.

Admixture - A substance other than cement, water, or aggregate added to a batch of fresh concrete to alter one of the normal properties of concrete.

Aggregate - Mineral material, such as sand, gravel crushed stone, slag, or the combinations thereof, with which cement or bituminous material is mixed to form a mortar or concrete. "Fine Aggregate" may be considered as the material that will pass a 1/4-inch screen and "coarse aggregate" as the material that is retained thereon.

Aggregate Base - The layer of specified, compacted material placed on the subgrade to serve as a base for pavement.

Agitation - Slow stirring or turning over of freshly mixed concrete to keep it in workable condition until placed into forms.

Air Entrained Cement - Cement into which the air entrainment admixture has been incorporated at the cement plant when the cement was ground.

Batch - The combination of amounts of cement, aggregate, water, and admixture which will be mixed at one time in a mixer.

Batching Operation - Proportioning and assembling the materials which will comprise one batch.

Batching Plant - The plant either on or off the work site where the materials are assembled by batches for the mixer. Water and admixtures usually are added as the batch is introduced into the mixer.

Batch Weights -The individual weights of the cement, aggregate, and water used in each batch of concrete. Aggregate is adjusted for moisture content and specific gravity.

Bleeding - Flow of water to the surface of freshly placed concrete.

Bulkhead - A partition made of timber, concrete, or steel plate between stockpiles to prevent their intermingling.

A temporary form placed at the completion of a portion of concrete structure or pavement, or whenever production is interrupted for an extended period of time.

Cement - A mixture of clay, limestone, and other selected materials heated to high temperature to form clinker. The clinker is then ground into powder. When mixed with water, it forms a paste to surround and bind the aggregate into a solid and durable mass.

Charging - Filling. Charging a mixer is placing the ingredients for concrete into it.

Compacted - Made denser. When a material is compacted, the particles are forced together more tightly so that a given weight of material takes up less space.

Concrete Control Inspector - The Inspector at the job site who is responsible for the necessary inspections and tests to ensure concrete meeting specifications.

Counters - Meters on mixers which show the number of revolutions. Transit mixers may have two counters - one for mixing speeds and one for agitation speeds.

Cure - The treatment given concrete to ensure sufficient water and heat necessary for chemical action so that concrete attains the strength and durability for which it was designed.

Entrained Air - Millions of microscopic voids introduced into concrete through an admixture to permit the cured concrete to undergo freezing and thawing without damage.

Entrapped Air - Large air bubbles which enter concrete through mixing or handling. Being undesirable, they can be removed by vibrating, spading, or rodding.

Falsework - The bracing supporting concrete structural forms which are removed after the concrete has cured sufficiently to support its own weight.

Finishing - Shaping the surface of cement that is not shaped by forms. Also, it includes filling visible voids in the concrete after the forms are removed.

Footer - The concrete pad which spreads the load of a structure over an area of supporting earthwork.

Forms, Report - Printed sheets of paper which contain blank spaces for filling in desired information.

Forms, Structural - Molds of rigid material for receiving plastic concrete which will cast it to a specified shape and dimension.

Gradation - The classification of different sizes of aggregate within a given size of aggregate as determined by sieve tests.

High-Early-Strength Concrete - Concrete made with a special cement (Type III) that reaches design strength and hardness in considerably shorter time than concrete made with regular Portland cement.

Honeycombing - Large voids in the concrete which are due to inadequate spading or consolidating.

Intermingling - The unintentional dilution of one size of aggregate by aggregate of a different size as a result of improper storage or careless handling.

Job Control - Steps taken to keep quality and quantity of materials and work on a project within the specifications and plans.

Mixing - Combining the ingredients of a batch of concrete into a homogenous mass through raising and dropping action of a revolving drum.  Specifications cover the rate and number of revolutions which are acceptable for proper mixing.

Moisture Content - The percentage by weight of water contained in aggregate as compared to the same aggregate in a completely dry condition.

Mortar - A mixture of water, sand, and cement. Mixed with coarse aggregate, this mortar completely envelopes each particle of coarse aggregate to form concrete.

Paved - An area covered with a hard surface to support traffic or material storage.

Plant Bins - Bins at the hatching plant for temporary storage of aggregate and cement for use in proportioning concrete batches.

Proportioning Concrete - Determination of the amount of each ingredient used in a class of concrete with adjustments as determined by tests called for in the specifications.

Retarder - An admixture placed in concrete which slows the setting of the concrete.

Rodding - Consolidation of a concrete mix sample by the repeated insertion of the prescribed steel tamping rod.

Saturation - Condition of aggregate when it is completely soaked and will not absorb additional water.

Scaling - Peeling away of small amounts of surface concrete.

Segregation - The unintentional separation of the larger pieces of aggregate from the smaller pieces within one size of aggregate or within a mixture of sizes in fresh concrete.

Set or set-up - A stage reached by freshly placed concrete as it hardens and can no longer be worked or shaped.

Sieve Analysis - Determination of the gradation of an aggregate sample by passing through a series of screens with specified openings and weighing the separated particle sizes.

Slump - A measure of the consistency and workability of plastic concrete.

Spading - Repeatedly inserting a flat steel blade edgewise into fresh poured concrete for consolidation and to drive out entrapped air, particularly where the concrete meets the forms or imbedded objects.

Spading Blade - A small steel blade about the size of a nail file used in making Chace air determinations.

Spading Tool - A tool resembling a garden hoe with the blade straightened out in line with the handle which is used for consolidating concrete.

Spalling - The breaking away of hardened parts of concrete from the main body at surface points.

Specific Gravity - The ratio of weight of any volume of a substance to the weight of an equal volume of water.

Specifications - The directions, provisions, and requirements contained in the State of Ohio Department of Transportation Construction and Material Specifications as supplemented by the supplemental specifications and special provisions.

Stabilize - To make or hold steady and prevent fluctuations.

Stockpile - A large amount of aggregate placed in a pile for storage until ready for use.

Strike Off - Using a straightedge to scrape off excess concrete which may protrude above the mold or forms.

Subgrade - The portion of a roadbed upon which the pavement structure and shoulders are constructed.

Testing Equipment - That equipment furnished to the project for conducting field tests.

Test Weights - Ten 50-pound (22.7 kg) steel weights that must be readily available for checking weighing devices at concrete plants.

Ticket - A form record of quality, quantity, and other pertinent information which may accompany a shipment of construction materials to the project.

Validation - The signature or initials of an authorized individual on any form or ticket denoting that the information is as stated.

Verification - The steps necessary to determine that the work or materials described are in conformance with plans and specifications.

Water-Cement Ratio (W/C) - The proportion of an amount of water to the specified amount of cement used to produce concrete. Such amount of water is the sum of the calculated amount of water contained in the aggregates, plus all the water added both at the plant and at the site, less the calculated amount of water absorbed by the aggregates.

Yield - A check on the mix design made by dividing the total batch weight by the determined unit weight, weight per cubic yard (weight per cubic foot). The actual volume thus obtained is compared to the design volume.

Rigid Pavement Terms

Admixture - A substance other than cement, water, or aggregate added to a batch of fresh concrete to alter one of the normal properties of concrete.

Aggregate - Mineral material, such as sand, gravel, crushed stone, slag, or the combination thereof, with which cement is mixed to form a mortar or concrete. “Fine aggregate” may be considered as the material that will pass a 4.75 mm (No. 4) screen and “coarse aggregate” as the material that is retained thereon.

Batch - The combination of amounts of cement, aggregate, water, and admixture which will be mixed at one time in a mixer.

Batching Plant - The plant either on or off the work site where the materials are assembled by batches for the mixer.  Water and admixtures usually are added as the batch is introduced into the mixer.

Beam, Test - A beam of specified size molded on the job and later broken in a testing machine to determine the flexural strength of the concrete.

Bleeding - Flow of water to the surface of freshly placed concrete.

Cap - A short tube, closed at one end, placed on the oiled end of a dowel in an expansion joint to provide space for movement of the dowel in hardened concrete. A stop in the tube prevents it from being pushed all the way onto the dowel before the concrete hardens.

Cement - A mixture of clay, limestone, and other selected materials heated to high temperature and ground into powder.  When mixed with water, it forms a paste to surround and bind the aggregate into a solid and durable mass.

Contraction Joint - A joint which controls the location of a transverse crack and permits the slab to contract and expand with changes in temperature.

Construction Joint - A joint formed in concrete pavement at the end of the day’s production or any time production is interrupted for 30 minutes or longer.

Core - A cylinder of concrete cut from pavement with a hollow drill. Cores are 4 inches (200 mm) in diameter and are used to check the thickness and strength of the concrete.

Course - The depth of concrete pavement obtained in one pour.

Crown - The height of the center of the roadway surface above a straight line drawn between its edges.

Cure - The treatment given concrete to ensure sufficient water and heat necessary for chemical action so that concrete attains the strength and durability for which it was designed.

Curing Membrane - A compound sprayed over the exposed surface and edges of newly placed concrete to prevent the evaporation of water during curing.

Cylinder - A test sample of concrete molded into a cylinder 12 inches (600 mm) high and 6 inches (300 mm) in diameter, to be sent to the Laboratory for determination of strength and density.

Deformed Bar - A steel bar which has projections on its surface for increasing the bond between the concrete and the bar.

Density (Soil) - The density of soil is its weight-volume relationship, which usually is expressed in pounds of soil per cubic foot (kilograms of soil per cubic meter).

Dowel or Dowel Bar - A smooth steel bar extending across a concrete joint to transfer the applied load, prevent future misalignment of the slab, and permit movement at the joint.

Dowel Assembly - A cage or basket used to hold dowels in position during placement of concrete.

Edging - Rounding the edges of concrete pavement and hand-formed joints while the concrete still is workable, using an edging tool of specified radius.

Elevation or Grade - The height as measured from a predetermined point denoted in the plans.

Expansion Joint - A joint adjacent to a bridge or intersection to absorb expansion of concrete pavement and prevent expansive pressure on the bridge or intersecting pavement.

Fine Grading - Removing approximately 1 inch (25 mm) of the primary subbase and re-rolling to bring to exact grade upon which the concrete pavement is placed.

Finishing - Shaping the surface of concrete that is not shaped by forms.  Also, it includes filling visible voids in the concrete after the forms are removed.

Finishing Machine - A machine, which screeds, and a float for performing the final grade and smoothness of the concrete pavement to meet the requirements.

Float - A straight piece of wood or metal used to smooth the surface of plastic concrete. Small hand-held floats are called paddle floats.

Forms, Pavement - Metal plates secured together and to the subbase for shaping the sides of the pavement and controlling alignment, grade, and thickness.  Also, the forms serve as a track for paving equipment.

Grade (noun) - See Elevation.

Grade (verb) - To add or remove earth to obtain a desired level or slope.

Hand Finishing - Manually correcting irregularities left by the finishing machine, or performing those functions which cannot be accomplished by machine, such as edging or forming of joints.

Head - The roll of plastic concrete which forms ahead of a screed plate.

Honeycombing - Large voids in the concrete which are due to inadequate spading or consolidating.

Hook Bolt - A short steel bar with hooked ends joined by a threaded connection.  Used to fasten a concrete slab to another, which is constructed beside it later.

Inspection - Examination by observation, measurement, or tests to determine that materials and work are in conformance with specifications.

Joint Lock - The device at each end of a section of paving form for attaching the sections together.

Job Control - Steps taken to keep quality and quantity of materials and work on a project within the specifications and plans.

Joint Sealer - A compound for preventing entrance of water and solid particles into a joint. The sealer may either be preformed or liquid.

Laitance - An accumulation of fine particles on the surface of freshly placed concrete occurring when there is an upward movement of water through the concrete due to the presence of too much mixing water or excessive vibration.

Lane or Traffic Lane - A strip of pavement of specified width, usually 12 feet (3.6 meters).

Longitudinal Joint - A joint which extends lengthwise on the roadway, parallel to the centerline.

Mesh - A fabric of steel wires welded together at their intersections for placement in concrete pavement as distributed reinforcement.

Mesh Installer - A machine for imbedding wire mesh into freshly placed concrete pavement.

Mortar - A mixture of water, sand, and cement.  Mixed with coarse aggregate, this mortar completely envelopes each particle of coarse aggregate to form concrete. Also, mortar is used to fill honeycombing which becomes apparent upon removal of forms.

Oscillating - To swing back and forth, operating between fixed limits, such as the movement of a screed on a finishing machine.

Pin Template or Template - A device used to check the surface of the subbase.

Raveling - Slightly disturbing the surface of concrete pavement adjacent to sawing of a joint.

Random Cracks - Cracks which appear in concrete pavement due to contraction in the early stages of curing and follow no set pattern.

Rigid Pavement Inspector - An authorized representative of the Engineer to make detailed inspections and documentation of contract performance as it pertains directly to concrete paving operations.

Sawing - Using a circular saw to cut a groove in the surface of the pavement to control the location of transverse cracks.

Scaling - Peeling away of small amounts of the concrete surface.

Screed - A long metal plate moved across the surface of freshly placed concrete with a sawing motion to consolidate the concrete and rough finish it approximately to grade.

Segregation - The unintentional separation of the larger pieces of aggregate from the smaller pieces within one size of aggregate or within a mixture of sizes of fresh concrete.

Shim - A thin piece of stone, wood, or other material used to raise the object resting on it to the desired elevation. (Not permitted in adjusting forms to grade).

Slab - A continuous portion of concrete paving bounded by joints and/or the edge of the pavement.

Slip Form Paving - Concrete paving by use of a machine carrying its own forms between which low slump concrete is compacted sufficiently to retain its shape after the machine has progressed onward.

Slump - Measured in millimeters (inches) on a vertical axis. The amount that a sample of fresh poured concrete, which has filled a standard inverted cone, will sink down after the cone has been removed.  A measure of the consistency and workability of concrete.

Spading - Repeatedly inserting a flat steel blade edgewise into fresh poured concrete for consolidation and to drive out entrapped air, particularly where the concrete meets the forms or imbedded objects.

Spalling - The breaking away of hardened parts of concrete from the main body at surface points.

Spreader - A machine which distributes fresh concrete generally over the area between the forms.

Station Marker - A numeral impressed into the surface of newly finished concrete pavement and located at specified longitudinal intervals near the edge of the roadway for purposes of future location references.

Straightedging - Placing a 10 foot (3.0 meter) straightedge on the finished pavement surface to determine if the surface is within tolerance.

Strike Off - Using a straightedge to scrape off excess concrete which may protrude above the mold or forms.

Subbase - The layer of specified, compacted material placed on the prepared subgrade to serve as a base for pavement.

Subgrade - The portion of a roadbed upon which the pavement structure and shoulders are constructed after it is prepared.

Surge - The rise in the surface of plastic concrete following the release of compaction after the screed has passed over it.

Texturing - Slight roughening of the finished surface of concrete pavement to provide greater safety through increased traction to the tires of vehicles which will pass over it.

Thin-Bonded Patching - Repairing concrete pavement only to the depth of unsound concrete rather than the full-depth of the pavement.

Tie Bar - A deformed dowel or hook-bolt placed across longitudinal joints of concrete pavement near middle-depth to tie the slabs together and hold the joint closed.

Tying - Wiring together overlapped mesh that is hand-tied by use of rings similar to hog rings.

Tolerance - The permitted variation from a specified condition.

Traction Speed - The rate of forward movement parallel to the centerline by the paving equipment.

Transverse - A theoretical line running perpendicular to the longitudinal or centerline of a roadway.

Validation - The signature or initials of an authorized individual on any form or ticket denoting that the information is as stated.

Vibrator - A device for pulsating fresh concrete so that entrapped air is released, and the concrete settles uniformly about reinforcement and to the forms.

Wearing Plate - A small plate which drags over the top of the pavement forms or adjacent paving to control the height of the screed plate.

Windrow - An accumulation of material as a result of rolling up or sliding off to the side. Applies here to loose material just inside of the forms left by the subgrader in the fine grading operation.

Yield - A check on the mix design made by dividing the total batch weight by the determined weight per unit volume. The actual volume thus obtained is compared to the design volume.

Earthwork

Aggregate Correction Method - A method of compaction testing that modifies the one point proctor method. It accounts for the material retained on the 3/4-inch sieve.

Atterberg Limits - The moisture content of a soil at certain stages of soil behavior.

Balanced Project - A project where the amount of embankment is required approximately equal to the amount of excavation.

Benching - The excavation of the existing embankment steps into a slope where new embankment is being placed on the slope.  The benching connects the new embankment and the existing soil in the slope.

Blasting - The use of explosives to fracture rock or shale.

Borrow - Material obtained from approved sources that are required for the construction of the embankment.

CA-EW-12, Daily Earthwork Inspection Sheet – This form details the earthwork construction operations on the project. It details general project information, locations of the operations, construction equipment, soil types, lift thicknesses, and other information.

CA-EW-5, Nuclear Gauge Compaction Form – This form details the record keeping for compaction tests.  The one point proctor and test section methods A and B use this form.

CA-EW-6, Nuclear Gauge Compaction with an Aggregate Correction – This form details the record keeping for a compaction test. The aggregate correction method of compaction testing uses this form.

Canvas Shroud - A canvas curtain used to control dust during the spreading operation.

Cement - A burned and pulverized chemical that that reacts with silty and granular soils.

Centrifugal Force - The roller force or load on a base course or material that adds the weight and the vibration energies.

Checking - The cracking of a base course or stabilized subgrade due to over rolling.

Clearing - Cutting down trees and brush.

Compaction - Increasing the density of soil by mechanical means, involving the expulsion of excess air.

Compaction Equipment - Equipment used to compact materials.

Consolidation - The removal of water from a soil over time to increase its strength.

Construction Underdrains - Sacrificial underdrains placed to drain the subgrade.

Contractor Designed Chemically Stabilized Subgrade - Tests performed by the Contractor to determine the optimum percentage of chemical (cement, lime, or lime kiln dust) that will stabilize the soil.

Curing - The act of ensuring that the lime or cement stabilized soil is wet for at least five days.

Deflections or Rutting - The vertical movement of the subgrade during proof rolling.

Density - The proportion of soil mass or weight to the volume of the soil. It is commonly expressed in pounds per cubic foot.

Depth Checks - The measuring of the thickness of the base course or embankment material.

Disking - The act of using a disk to break up a material so that it may dry.

Dozer - A machine that pushes and levels material.

Drainage - Constructing the embankment to drain the water away as fast as possible.

Drainage Blanket - A system of coarse aggregate, fabric and pipe that is designed to drain large areas of the slope.

Dry Density – The density of a soil that uses only the weight of the soil. The density of the soil when the soil is completely dry.

Drying - The act of lowering the moisture content of a material by disking, plowing, or other means.

Earth Moving Equipment - Equipment used to move earthen materials.

Earthwork Volumes - The calculation of a three dimensional earthwork quantities.

Electronic Grade Control - Controls on construction equipment that controls the grade.

Embankment - A structure consisting of suitable materials and constructed in lifts to a predetermined elevation and cross-section.

End Area - The cross-sectional area on the plans that represents a two dimensional plane.

End Dumping - The direct loading of the base or embankment material from the truck to the subgrade or foundation.

Excavation - The removal of materials to predetermined elevations and cross-sections.

Excavator - A machine that removes material with a bucket.

Fine Grading - The act for trimming the surface to meet the specification tolerances.

Finished Surface - The top of the base or subgrade materials that has been fine graded or trimmed.

Footed Rollers - Rollers that knit the materials together. Primarily used for clayey materials.

Foundation - The location at the base of an embankment.

Gradation - The level of coarseness or fineness of a soil, referring to soil sizes.

Grader - A machine used to level surfaces.

Grading - The act of leveling the embankment surface to drain.

Granular Material Types - Granular Materials in Item 203 that have specific gradations to perform certain engineering functions.

Grubbing - Clearing by digging up roots and stumps.

Hydrated Lime - A finer form of lime.

Ingots - Heavy concrete weights in the proof roller.

Iron Slags - Air-Cooled Blast Furnace slag (ACBF) and Granulated slag (GS).

Lift Thickness - The thickness of the material when placed on a horizontal surface.

Lime - A by-product of limestone that reacts with clayey soils.

Liquid Limit - Moisture content at which a soil passes from a plastic to a liquid state.

Maintenance - The act of constructing an embankment that minimizes construction problems. For example, grading and draining to keep water off the embankment.

Moderately Soft Foundation - A foundation that is constructible with moderate changes to embankment construction techniques.

Moisture Content - The amount of water in a given soil expressed as a percent of the material’s dry weight.

Moisture Density Curve - A plot of the moisture content verses the weight of a soil. This plot determines their relationship.

Natural Granular Materials - Broken or crushed rock, gravel, sand, durable siltstone, and durable sandstone placed in 8-inch (200 mm) loose lifts.

Natural Soils - All natural earth materials, organic, or inorganic resulting from natural processes, such as weathering, decay, and chemical action.

Nuclear Gauge - A device that uses nuclear radiation to determine the soils’ density and moisture content.

Ohio Typical Density Curves - Curves that were developed in the 1930’s and 40’s that represent all the types of soils in the state. They are used with the one-point proctor method to pick the correct curve during compaction testing.

One Point Proctor Method - a method that determines the compaction of a soil. It requires making a proctor and using the Ohio Typical Density Curves to pick the correct curve.

Optimum Moisture - The water content at which the maximum dry density can be achieved by compacting an embankment material.

Partial Excavation Method - The act of removing only a portion of the soft material.

Pavement - The location above the subgrade that traffic runs on that is made of concrete or asphalt.

Plastic Limit - The moisture content at which the material breaks apart at a 1/8-inch diameter. Indicates how much clay is in the material. The moisture content at which a soil changes from a semi-solid to a plastic state.

Plasticity Index - The higher the PI, the more clay in the material. The numerical difference between the liquid limit and plastic limit.

Power Driven Mixer - A big roto-tiller used to mix the soil and the lime.

Prime Coat - An asphalt emulsion used to keep the lime soil moist for the cure period.

Proctor Hammer - A device that is used to compact a soil in a proctor mold. It weighs 5.5 pounds, compacts the soil 25 times for each soil lift in the proctor. The soil is placed in the proctor mold in three lifts.

Proctor Test – a procedure that uses a standard, compactive effort to determine or pick a soil moisture density curve.

Proof Rolling - The use of heavy rollers to test the subgrade stability.

Quick Lime - A coarser and more concentrated form of lime.

Random Material - Mixtures of suitable materials that can be placed in 8-inch (200 mm) loose lifts.

Rectangular Foot - A footed roller with rectangular feet.

Recycled Materials - Fly ash, bottom ash, foundry sand, recycled glass, tire shreds, RPCC, or RACP

Recycled Portland Cement Concrete (RPCC) - Recycled Portland cement concrete blended with natural soil or granular material.

Reclaimed Asphalt Concrete Pavement (RACP) - Recycled asphalt pavement blended with natural soil or granular material.

Rock - Sandstone, limestone, dolomite, glacial boulders, brick, and RPCC too large to be placed in an 8-inch (200 mm) loose lift.

Rock or Shale Subgrade Excavation - The 24 inches that is excavated below the pavement for drainage and uniform support.

Roller Pass - One pass over a given location.

Sand Blanket - The sand that is placed to drain the underlying soft material.

Saturated Embankment - Embankment that is full of water to the point of being unstable.

Scale – A weight measuring device used during compaction testing.

Scalping - Removal of remaining roots, sod, grass, agriculture crop, sawdust, and other vegetation so that the soil is completely exposed; however, topsoil should not be removed.

Scraper Plate - A device that is used to establish a location for the nuclear gauge.

Segregation - The separation of fine and coarse material in a base course.

Self-Propelled Spreading Machine - A piece of equipment that receives the base course from the truck and spreads it evenly on the subgrade.

Settlement - The compression of a soil into a more stable condition.

Severely Soft Foundation - Low lying areas with high or standing water that are not constructible with soil or standard construction techniques.

Shale - Laminated material with a finely stratified structure formed by the natural consolidation of a clay or silt. The material is sometimes cemented together.

Shale Compaction Testing – Compaction testing that uses a Bucket test to determine what compaction test to perform on a particular shale.

Sheepsfoot - An old footed roller that has 10 percent coverage per pass.

Side Drainage - Any ditches that drain the embankment away from the embankment construction.

Side Slopes - The embankment slopes that are perpendicular to the roadway (usually 2:1 slopes).

Slag Materials - Residual material from making iron or steel that must meet the requirements in 703.16.

Slide Repair - An area to be excavated for replacement.

Soil Classification - AASHTO classification of a soil determined from the gradation and characteristic of the different materials.

Spreading - Moving material in preparation for compaction.

Spring Drains - A system of coarse aggregate, fabric, and pipe that is designed to drain small areas of the slope.

Standard Count- a procedure performed on a nuclear gauge to ensure that the readings are accurate.

Steel Slags - Open Hearth (OH) slag, Basic Oxygen Furnace (BOF) slag, Electric Arc Furnace (EAF) slag, or Granulated slag.

Steel Wheeled Roller - Uses a drum with 100 percent coverage with one pass. Can be used with or without vibration. Used for granular and silty materials.

Stock Pile - A pile of material that has or will be approved by the Test Lab.

Straightedge - A piece of lumber with a level on it to check the grade.

Subgrade – The portion of the roadbed upon which the pavement structure and shoulders are constructed.

Subgrade Compaction - The compaction of the top 12 inches of the subgrade.

Suitable Material - Natural soil, natural granular material, granular material types, slag material, brick, shale, rock, random material, or other materials that are appropriate for use in embankment construction.

Tamping Foot - A footed roller that has 40 percent coverage with one pass and is highly productive. Can be used for soil, rock, or shale.

Test Rolling - The use of a proof roller to test the stability of the subgrade prior to undercutting or stabilizing the subgrade. Used when spot locations are detailed in the plans.

Test Section Method - A compaction method that uses the relative density between two nuclear gauge readings to determine the materials potential maximum density.

Test Section Method A - A compaction method that uses the relative density between two nuclear gauge readings to determine the materials potential maximum density. It is used when the material has a definitive moisture density curve.

Test Section Method B - A compaction method that uses the relative density between two nuclear gauge readings to determine the materials potential maximum density. It is used when the material does ‘not’ have a definitive moisture density curve. A field test section moisture density curve is developed with this method.

Test Section Method C - A compaction method that uses the relative density between two nuclear gauge readings to determine the material’s potential maximum density. It is used when the material is highly variable. It uses form CA-EW-7.

Total Excavation Method - Removing all of the soft material.

Waste - Excess material removed from the project limits.

Watering - The act of adding moisture to a material for proper compaction.

Weak Plane - An area in the embankment where the soil is weak and could slide apart.

Wet Density - the density of the soil that includes the weight of water and soil. It is also expressed as the total weight of the soil.

Zero Air Void Curve - A theoretical line that is used to ensure that the nuclear gauge readings are not dramatically incorrect. It plots the moisture density curve without the voids.

Landscape

Amendments - Mixed with the soil removed from the plant hole. To improve the soil texture or pH, add organic material. Sphagnum peat moss, shredded pine bark, yard waste compost, and sand are all accepted amendments.

Backfill - This soil and amendment mixture is placed back into the hole after the plant has been set (see C&MS 661.11).

Balled and Burlapped - This is one kind of method for digging field-grown plants with the ball of earth still intact in which they are growing. Can be supported by a wire basket and/or burlap and laced with bailing twine. Often denoted as B&B in plan notes. See appendix for correct plant/B&B sizes.

Bare Root - Plants shipped by this method are done so without the soil from which they were grown. This type of plant can be seedlings, perennials, roses, fruit trees, etc. Roots should be white and unbroken.

Caliper - This is measured as the width of a single stem plant. See Page 6 for instructions on how to measure.

Competing Leaders - Found at the top most branch. This condition is where the main stem (leader) has been cut or broken and has continued to grow into two main stems. One stem should be removed to eliminate the potential for future problems.

Conifer - Cone-bearing plants, mostly evergreen, but not always true.

Crown - The upper part of a tree, also called the canopy.

Deciduous - Term used to describe plants which lose their leaves at the end of a growing season. This typically occurs in the fall.

Fertilizer - A natural or synthetic material added to or spread on soil to increase its fertility. The three numbers indicate its percentage of ingredients. In order, these numbers are nitrogen, phosphorus, and potassium.

Foliage - This is the leaf structure of a plant, such as needles or deciduous leaves (can be composted).

Herbicide - A natural or synthetic product typically used to eradicate weeds. Product should be applied by a licensed applicator and as directed by the manufacturer’s label.

Mulch - Placed on top of the plants rootball. Mulch keeps the ground cool, retains moisture, prevents heaving, and breaks down providing nutrients to the root system (see C&MS 661. 13).

Multi-stem - Having two or more main stems; defined as clump or shrub form.

Root Crown - This is the union between the roots and the stem. Care should be taken not to bury this union with soil when planting.

Single Stem - Also called the central leader or trunk, tapers gradually from root crown to top.

Shrubs - Usually multi-stemmed with numerous side branches, can be evergreen or deciduous.

Tree Wrap - Placed around a deciduous tree trunk to protect it from frost cracking, sunscald, or insect damage (see C&MS 661.15).

105 Control of the Work

Overview of Construction Contracts – General ODOT Organization

Central Office

District Construction needs to communicate with the Central Office on many issues.  The primary contacts are within the Division of Construction and Division of Contracts. The Table of Organization for ODOT is shown below. 

http://www.dot.state.oh.us/SiteCollectionDocuments/ODOT_TO.PDF

The Central Office Division of Contracts responsibilities include policy and standard procedure development, support services, and quality assurance. More specifically, its role is to:

·         Work with other offices to develop specifications and policies that apply to the day-to-day operations at the project level.

·         Act as a liaison with other offices, the various trade organizations, and FHWA on matters concerning ODOT's specifications, policies, and procedures.

·         Act as a consultant to the Districts in matters concerning contract administration.

·         Provide training to the Districts in contract administration.

·         Review and report the effectiveness of various construction methods and materials and provide advice on their use.

·         Conduct Quality Assurance Reviews (QAR) to ensure that ODOT's policies, procedures, and specifications are being followed uniformly.

·         Develop the performance measures by which the Districts are judged.

·         Conduct the administrative closing of contracts.

·         Provide support to the Districts, Testing, and Estimating Offices.

The responsibilities described above are of a general nature. The Division of Construction also has some specific approval functions that relate directly to the District.  They are as follows:

·         Answer legal questions and provide dispositions regarding claims.

·         Answer pre-bid questions through the Office of Estimating.

·         Testify and report extra work to the State Controlling Board.

·         Create and publish the Construction and Material Specifications along with the quarterly publication of all other specifications.

·         Track and report on change orders and provide feedback to Production Offices.

·         Test materials and develop specification, including new product review.

·         Estimate analysis of trends, bid review, and change order support.

As mentioned above, the Division of Construction is responsible for the Office of Construction Administration, the Central Laboratory and the Office of Estimating.  The Office of Construction Administration has experts in the areas of concrete, asphalt, traffic, bridges, contracts, and scheduling who can provide advice to the Districts and initiate specification or policy changes.

The Division of Construction Management Policies and Standard Procedures can be found online at the following website:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Pages/ConstructionPolicies.aspx

District

All District responsibilities begin with the District Deputy Director (DDD). The DDD, through the Highway Management Administrator (HMA) and the District Construction Administrator, is responsible for the administration of all contracts sold for the construction, reconstruction, and maintenance of the highway system within the District.

While Central Office's responsibilities are primarily general in nature, the District's responsibilities are administration of all contracts. The following is a summary of various District responsibilities required by state policies and procedures as they relate to contract administration:

·         Ensure that all work done on each project is performed in accordance with the project's requirements (plans, proposal, specifications, supplemental specifications, special provisions, etc.)

·         Approve all change orders that do not require approval by the Director as defined in Section 109 of this Manual.

·         Approve all time extensions and waivers.

·         Review the contractor/subcontractor certified payrolls for compliance with the contract requirements.

·         Review the Contractor's performance and compliance with the contracts Equal Employment Opportunity requirements.

·         Approve all estimates for work completed on the projects.

·         Perform the final inspection and approve the final inspection report.

·         Review the project records to ensure that all requirements have been met.

·         Monitor Local Participating Agency (LPA) projects to ensure compliance with FHWA requirements.

·         Prepare and approve the Final Package on the project.

·         Issue the final acceptance letter and submit the finalized project to the Auditor.

In addition, the District is responsible for the following general project requirements and responsibilities:

·         Provide a description of the work through the plans, proposal, specifications, supplemental specifications, and special provisions.

·         Provide a method to pay for completed work.

·         Provide a project site with full access for the Contractor to begin work. This includes right-of-way purchases and utility relocations.

·         Furnish an adequate and trained inspection/engineering force at the project level.

·         Secure good workmanship by the Contractor. This involves the monitoring, by the project staff, of all operations for compliance with the documents described above.

·         Arrive at decisions in a thoughtful manner with due consideration of all facts involved.

·         Make decisions in a timely manner to avoid undue delay.

·         Promptly pay the Contractor for completed work.

·         Monitor the Contractor's compliance with the legal aspects of the contract, such as prevailing wage and equal employment opportunity requirements.

·         Review the Contractor's work zone traffic control to ensure the public can pass through the work zone with the least amount of interference.

·         Respond to any complaints or questions in a timely manner.

Almost everything done at the project level affects another party. Because of this, the project personnel are constantly subject to pressures from outside sources. Always be mindful of the needs of these parties, the effects of the project on them, their relationship to the project and their affect on the project.

District Construction Administrator

The general responsibilities and requirements assigned to each District rest in the hands of the District Construction Office and specifically the District Construction Administrator (DCA). This person, with the approval of the District Deputy Director and Highway Management Administrator, is responsible for the administration of the contracts involving the construction, reconstruction, and maintenance of the District's highway system as well as local projects involving state and federal aid on the state's system. The DCA is responsible for assigning personnel to projects for contract administration. In addition, the DCA will work to resolve any issues that arise on these projects at the lowest possible level.

County Manager

Each county is under the supervision of a County Manager. The County Manager will be involved with all work within the county and will ultimately be the owner of the construction end product.

Other Agencies

Although the primary parties to any contract administered by ODOT are the Contractor and ODOT, other political subdivisions may also be involved either directly or indirectly. During the administration of each project, these relationships should be recognized and addressed.

Federal Highway Administration

The Federal Highway Administration (FHWA) is involved in many projects administered by ODOT. Federal funds are available for many programs and are utilized by both ODOT and local political subdivisions for improvement to their roadway systems. Their involvement varies with the type of project and its location on the National Highway System (NHS). FHWA's philosophy for review of federal aid projects has evolved over the years and now is as follows:

·         Major projects on the National Highway System will continue to receive the most attention from FHWA. FHWA will be involved from preliminary design to finalization. This will include periodic reviews to monitor the project's progress and participation in the final inspection.

·         FHWA, with the advent of ISTEA, has taken a step back in the tight oversight that had existed on all federal aid projects. On most federal aid projects, both with ODOT or local participation, FHWA has minor on-site participation. FHWA does not get involved with the project specifically, but expects ODOT to administer these projects in accordance with the plans and specifications and then certify that this has been done.

·         FHWA will still participate in reviews of ODOT’s policies, procedures, and specifications. At the project level, this may involve a review of an individual process (paving, traffic control, etc.) that is also being studied statewide.

Local Participating Agency

Many contracts involve direct local participation. The Local Participating Agency (LPA) will provide funds for their portion of the contract and the remainder of the funds may be provided by either FHWA or ODOT or both. These projects may be administered by the Local or the Department.  If the Local administers the project, the Department will monitor the project through the District Construction Monitor.  See the Locally Administered Transportation Project Manual of Procedures for guidelines. 

If ODOT administers the project, the LPA will still have to live with the project after completion. Therefore, with this in mind, ODOT should invite the LPA to the preconstruction meeting and all progress meetings.  In addition, ODOT should keep the LPA informed about all changes to the contract.  This is especially true when dealing with changes requiring large increases in the local participation.

The LPA must be involved in the final inspection.  Additionally, the LPA must give their final approval and acceptance to the project.

Administration of Construction Contracts at the Project Level

In order to implement both the letter and spirit of any contract, it is necessary to have clearly defined lines of authority and communication between ODOT and the Contractor. This section will present a framework to establish these lines.

The purpose of this section is to give guidance to the project personnel on how to administer the physical work of the contract.

Authority / Responsibilities of the Engineer (105.01)

The Engineer is in charge of all details on the assigned project. The Engineer is the direct representative of the Department and has immediate charge of engineering details of each construction project.  The Engineer is responsible for the administration and satisfactory completion of the project.  The Engineer has the authority to reject defective work, suspend work being improperly performed, and order the replacement of defective material.

It is important to note that the Engineer’s acceptance does not constitute a waiver of the Department’s right to pursue any and all legal remedies for defective work or work performed by the Contractor in an unworkmanlike manner.

The Engineer is responsible for the following:

·         Assignment of the inspection duties at the project level.

·         Instruction of the inspection force in the requirements of the project and the items being constructed including:

o    Addenda, proposal and supplemental specifications, and equipment (e.g., concrete testing kit).

·         Review of materials to be incorporated in the work. This may involve rejection of materials.

·         Timely payment for work performed by performing the following activities:

o    Input daily diaries on SiteManager, review estimates, verify payrolls, and obtain approval of sampled materials.

·         Determining the need for change orders within the scope of the contract.

·         Monitoring the project and discussing progress schedule with Contractor's Superintendent.

·         Maintaining project records:

o    Construction daily diary, CA-D-3 or 4.

o    Work performed. Contractor's equipment, materials, and significant events of the day.

o    Job correspondence.

o    Letters from contractors, utility companies, and other public agencies, as well as any correspondence from District or internal agencies.

o    Minutes from project progress meetings, including who attended, items discussed, and resolutions to problems.

o    Other pertinent documents.

o    Shop drawings, working drawings, and erection procedures.

·         Addressing and resolving job site problems in a timely manner.

·         Providing the Contractor with specific information regarding the usage of contingency quantities or "as directed" items.

·         Reporting to District Construction Administrator any major change in conditions, traffic accidents, or status of project.

·         Determining final quantities, ensuring the Contractor completes the Punch List items, completing project files, and scheduling final inspection.

Authority / Responsibilities of the Inspector (105.09)

The Inspector is the front line ODOT representative at the project level.  The Inspector has authority to inspect all work performed and materials used. The Inspector also has authority to reject non-conforming materials and to suspend operations until problem is resolved by Engineer. The Inspector can neither alter the contract nor issue orders contrary to the contract.

The Inspector is responsible for the following:

·         Inspection of all work performed. This inspection will be done in accordance with ODOT policies and this manual and includes daily record keeping.

·         Reporting quantities of work satisfactorily completed in the units established by the contract.

·         Data entry into SiteManager, Inspector's daily diary, CA-D-3 or 4, AP-1, drawings of work performed

·         Inspecting and sampling the materials incorporated into the work.

·         Rejecting unsuitable materials and suspending operations until an issue is resolved by the Engineer or DCA.

·         Inspection of the material incorporated into the project.

·         Being familiar with manuals and specifications of items of work being inspected.

·         Communicating daily issues to the Engineer.

·         Communicating with Contractor to ensure proper installation of work.

The Inspector cannot waive the Department’s right to pursue any and all legal remedies for defective work or work performed by the Contractor in an unworkmanlike manner.

Authority / Responsibilities of the Contractor

The Contractor's Superintendent is responsible for the work.  He/she must be capable of reading and thoroughly understanding the plans and specifications and be experienced in the work. There will be only one superintendent who shall have full authority to execute instructions of the Engineer and shall be in charge of all construction operations regardless of who performs the work.

The Engineer should know if the Superintendent can agree to extra work, get the equipment needed to get the job done, and know if they can follow through with final quantities agreed on.

The Contractor must provide a superintendent on the project at all times.  The Superintendent is responsible for all aspects of the work, irrespective of the amount of work subcontracted.

The Contractor bears sole responsibility for the quality of work and compliance with the contract regardless of the Department’s level of inspection.

The Contractor is responsible for the following:

·         In order to submit a bid that adequately reflects the conditions of the contract, the Contractor must research all aspects of the contract, such as visiting the project site, understanding the plan notes, and reviewing all plan requirements.

·         The Contractor must notify ODOT of the project's starting date and keep ODOT informed of the proposed schedule of operations. This allows ODOT to anticipate engineering and inspection needs and therefore, efficiently manage staff.

·         The Contractor must provide a list of material suppliers. ODOT will review the proposed list and obtain required samples. The list should be submitted early to avoid delays associated with sampling and testing.

·         The Contractor must carry out the work on the project in a diligent manner utilizing adequate labor.

·         In order to manage the project efficiently and to avoid project related problems, the Contractor must be aware of all federal, state, and local laws that apply. Many of the legal requirements of the contract are addressed in the proposal, but the Contractor must also be aware of other regulations, such as safety, which is not thoroughly detailed in ODOT's specifications, but is extremely important. ODOT requires the Contractor to protect and indemnify ODOT from all claims and liability resulting from negligence or willful violations.

·         When open to traffic, the Contractor must maintain the project in order to permit the public to move safely through. This includes using clean, readable signs, traffic control devices, and maintaining the project free of debris.

·         Once notified of problems, the Contractor must respond quickly to correct the problem. This is extremely important when public safety is involved.

Coordination of the Contract Documents (105.04)

Contract documents are prepared to promote agreement between the various parts of the plans and specifications that control the work. In case of disagreement between the plans and specifications, the following will govern in descending order:

·         Addenda

·         Special provisions/proposal

·         Plans

·         Calculated Dimensions

·         Scaled Dimensions

·         Supplemental Specifications

·         Standard Specifications

The Contractor shall take no advantage of any apparent error or emission in the plans or specifications. In the event the Contractor discovers such an error or emission, the Contractor shall immediately notify the Engineer.

Proposal

The proposal details numerous bidding, EEO, regulatory, special issues, and general requirements of the contract.  The proposal may include details for incentives and schedule requirements.  It also includes a list of bid items and the wage rates that are in effect for the project.  The proposal language overrules all plan and specification items.

Plans

The plans show details of structures, the line, grades, typical cross-sections of the roadway, and the location and design of structures. The Contractor shall, at all times, keep one set of project plans available at the project site. No changes shall be made to the plans except as approved by the Engineer.

Working Drawings

The plans shall be supplemented by working drawings when required to control the work adequately. Working drawings shall be furnished by the Contractor. Working drawings shall not be prepared until the applicable field and plan elevations, dimensions, and geometries have been verified by the Contractor. Specific items of work shall require working drawings. These requirements are stated in the specification section that is applicable to the item of work. See table below for typical examples of number of copies and where to submit the different types of working drawings.

ITEM

DRAWING

COPIES

DESTINATION

501.05

Structural steel and other metal items, prestressed concrete members, precast concrete structural elements joint sealing devices and other similar items requiring either shop or field fabrication

3

Central Office

630

Overhead sign support

2*

District

630

Roadside sign support

2*

District

632

Signal poles

2*

District

632

Traffic signal heads

2*

District

*              Certified Working Drawings Section 625.06, 630.03

Construction and Material Specifications

Sections 200 thru 600 of the Construction and Material Specifications are used to obtain the workmanship compliance required for each item. These specifications are typically arranged in the following manner:

·         Description

·         Materials

·         Construction Requirements

·         Method of Measurement

·         Basis of Payment

Section 700 of the Construction and Material Specifications describes the material requirements. 

Supplemental Specifications (SS) are stand-alone specifications that usually have their own pay items. 

The SS800 is a specification called out on every project that provides corrections, revisions, and updates to the Construction and Material Specifications.

Cooperation with Utilities (105.07)

Utilities will be encountered on most construction projects. The proposal will include a utility note that designates the utility names and times that they will be relocated.  The plans should include the detailed locations of the utility changes. If the utility owners fail to relocate or adjust utilities as provided for in the contract documents and the Contractor sustains losses that could not have been avoided by the judicious handling of forces, equipment, and plant, or by reasonable revisions to the schedule of operations, then the Engineer will adjust the contract by change orders.  Change orders associated with utilities should properly denote one of the following reasons codes:

14,  UTILITY RELOCATION DELAY.

15,  IMPROPERLY LOCATED UTILITY.

16,  UNKNOWN UTILITY.

17,  DELAY CAUSED FOR REASONS OTHER THAN UTILITIES.

Haul Roads (105.13)

Prior to hauling equipment or materials, the Contractor will provide written notification to the Engineer of the specific roads or streets on the haul route.  The following procedure should be followed:

·         The Contractor requests, through ODOT, that certain local roadways be used for hauling material and equipment to and from the project.

·         ODOT reviews the request and contacts the LPA.

·         If there is no objection by ODOT or the LPA, the roadway is designated as a haul road.

·         The roadway's condition is reviewed prior to hauling.

·         If, during the course of the project, the roadway becomes dangerous, ODOT will have the Contractor repair it.

·         Once the project is completed, the condition is reviewed again.

·         The roadway will be restored to its original condition either through the contract or by other means.

Borrow and Waste Areas (105.16)

The purpose of this section is to establish uniform practices for administering borrow and waste areas on or off the right-of–way.  It is the Department’s policy to approve requests to locate borrow and waste areas providing that:

·         The location would not adversely affect the highway.

·         The material is disposed of legally.

·         The disposal minimizes the Department’s future liability.

·         All environmental laws are observed.

·         The offsite locations are serving the public and land owners best interest.

·         The areas are restored according to the contract.

Material from outside the right-of-way used in embankment construction is considered to be borrow even though it is not paid for as borrow.  Therefore, this section applies to all borrow and waste areas, including areas from which material is furnished and paid for under “203 Embankment,” as well as areas from which material is furnished and paid for under “203 Borrow.”

Requests from the Contractor to locate borrow and waste areas shall be directed to the Engineer, who shall either approve or disapprove the request.  Action on each request shall be based on the information contained in the plan submitted by the Contractor, approvals from other ODOT Offices, certifications from environmental consultants, and other supplemental information available to the Engineer.

See Section 107.10 for criteria for evaluating borrow and waste environmental and other significant issues.

General Approval

Specific considerations, which are made a part of the general conditions for approval include, but are not limited to the following:

1.        All of the general information listed in A through G of 105.16 is addressed in the Contractor’s submittal.

2.        For borrow and waste areas which will not become ponds when the work is completed:

a.        The area shall be graded to ensure positive drainage.

b.        Restoration of all borrow and waste areas shall include cleanup, shaping replacement of topsoil, and establishment of vegetative cover by seeding, and mulching according to 659.

3.        For pits which will become ponds when the work is completed:

a.        In general, ponds are not considered objectionable, and often are considered highly desirable by property owners and persons engauged in conservation of natural resources and wildlife.  The creation of additional ponds from borrow pits can provide enhanced environmental benefits providing that they are constructed properly to avoid shallow stagnant water and are left in a condition to present an aesthetically pleasing appearance.  If the pond is on the right-of-way, then approval should be sought from the County Manager and District Production since the District may not want to take the long-term responsibility for the pond.

4.        Borrow Pit Final Grading:

a.        The tops of the pit slope shall be at least 25 feet (8m) from the highway right-of-way.  This distance may be increased if there are slope stability or erosion problems.  Twenty-five feet (8m) has worked well in the past.

b.        Borrow pit slopes adjacent to the highway shall not be steeper than 3 to 1, and all other borrow pit slopes shall not be steeper than 2 to 1.

c.        The borrow pit must be left in a condition satisfactory to the Engineer to blend with adjacent topography when the work is completed.

Stability and Settlement Concerns

Slope stability problems resulting from borrow and waste area construction is the sole responsibility of the Contractor.  The Department is keenly interested in the Contractor’s filling and cutting operations.  The Department must assess the potential for settlement and future slides. The proper design and construction of the borrow and waste areas are provided in 105.16 and references in the Location and Design Manual.

Most of the stability and settlement issues can be evaluated by using the following general guidance:

1.        If the material is placed according to C&MS, use a maximum slope of 2:1.  Use a 3:1 slope if the embankment is higher than 30 feet (9 m).

2.        Only end dump in nonstructural locations.  Use a 4:1 slope if the material is end dumped.  These areas may need to be re-graded at some future time.  Large settlements should be anticipated if the material is end dumped in lifts greater than 3 feet (1 m).

3.        Areas with soft foundations should be closely evaluated when the fill height is greater than 20 feet (6.1 m).

4.        If the off-site location exceeds the above criteria, or when constructing a non-structural fill, then the property owner should be explicitly told in the agreement with the Contractor.  The borrow or waste agreement must explicitly state that the property owners know that these location may settle and potentially slide.  If this is not explicitly stated, then the public may be misled in believing that the final fill will be stable.  The Department has a stake in making sure that the property owner is not misled.

5.        For proposed locations in the right-of-way that exceeds the above criteria or looks suspicious, contact the District Geotechnical Engineer or the Office of Geotechnical Engineering.

Construction and Demolition Debris (105.17)

The EPA regulates materials that come from structure removal, pipe removal, clearing or grubbing, and tree and brush removal operations. The EPA encourages the reuse of construction materials. 

The OAC 3745-37, OAC-3745-400, and ORC Chapter 3714 regulate the use and disposal of this material.  The law is governed by the OEPA or the Local Boards of Health, whichever has jurisdiction.  The law governs the debris from construction sites that are not covered under solid or hazardous waste or other regulations.  Use the following links:

http://codes.ohio.gov/orc/3714

http://codes.ohio.gov/oac/3745-27-01

By the EPA definition, construction and demolition debris is the material resulting from the alteration, construction, destruction, rehabilitation, or repair of any manmade physical structure.  Those materials are those structural and functional materials comprising the structure and surrounding site improvements (e.g., fences, sidewalks).  The definition identifies structures that are included and materials that comprise the structure, which are considered debris.  Any materials that are removed prior to demolition or are not part of the structure and surrounding site will not be considered debris.

The contract documents may require TCLP (Toxicity Characteristic Leaching Procedure) testing of the debris prior to transport and disposal.

Debris does not include materials identified or listed as solid wastes, infectious wastes, or hazardous waste. 

The rule identifies other process materials (e.g., mining operations, non-toxic fly ash, etc.) that are not debris. 

The legal removal and disposal of all of the following materials are the responsibility of the Contractor.  The specifications have been radically changed to address these issues. All parties to the project should monitor the Contractor’s work to minimize the Department’s future liability.

Clean Hard Fill

Clean hard fill material (asphalt millings) or Portland cement concrete material (or mixtures of these materials with soil, aggregate etc.) coming from pavement or structural removal operations.  Clean hard fill may be used as:

·         Fill, recycled, or taken to an approved Construction and Demolition Debris Site.

·         Fill on or off the project provided the material is acceptable under Item 203.  If the material is being used as fill off the site, the OEPA or local board of health in the area of the filling operations needs written notification seven days prior to the filling operation.  See the definition of “on-site.”

·         These materials cannot be indiscriminately piled up and left.  These materials must be placed in fill areas not in disposal piles.

·         May be taken to a recycling operation for recycling and storage.  Storage must be less than two years.

Construction Debris

Construction Debris such as wood, plaster, etc. in whole or mixed with clean hard fill. 

These materials are:

·         Usually associated with building debris.

·         Do not meet the 203 embankment specifications and cannot be used in fill operations.

·         Must be taken to an approved construction demolition debris site or licensed solid waste disposal facility.

Landscape Wastes

This law also regulates the disposal of landscape waste that result from roadway clearing and grubbing operations.  Landscape wastes include brush, trees, stumps, tree trimmings, branches, weeds, leaves, grass, shrubbery, yard trimmings, crop residue, and other plant matter, excluding soil and garbage.  The Department of Agriculture and the local authorities regulate the transportation of this waste to prevent the spread of the Emerald Ash Borer and the Asian Longhorned Beetle.

These wastes may be re-used by:

·         Constructing a wildlife habitat according to published guidelines from the Ohio Division of Wildlife, U.S. Fish and Wildlife Services, or Natural Resources Conservation Services.  This is subject to local board of health or local OEPA approval.

·         Chipping waste into mulch and using or donating it for use on- or off-site.

·         Selling or donating the waste for non-burial beneficial purposes.

·         Using the waste for any beneficial use or re-use approved by the local OEPA Offices or the local board of health.

·         Using the waste as fill material on-site from which the waste was generated. Item 203, Embankment, does not allow these wastes in embankments or structural areas.  On-site placement is permitted in non-structural areas. See 105.16, Borrow and Waste, “Stability and Settlement Concerns,” in this manual. OEPA guidance for on-site means any location on the right-of-way.  This can be outside the construction limits or even on other state owned properties.  If large amounts of these wastes are to be generated, then the Designer may provide specific right-of way locations to dispose of these wastes. See the Borrow and Waste Areas (105.16) section, “Approval of Wasting on the Right-of-Way,” in this manual.

All landscape wastes associated with ODOT projects are required to be disposed of at an appropriate landfill. 

These wastes may be disposed of by:

·         Open burning (requires special permitting of OEPA, local authorities, special equipment, and site management).

·         Composting at an OEPA registered composting facility.

·         Sending material less than 4 inches (10.6 cm) in size to a sanitary landfill and materials greater than 4 inches (10.6 cm) in size to a construction and demolition debris landfill.  Leaves cannot be taken to a construction and demolition debris landfill.

Portland Cement Concrete Waste

In recent years, we have increased the amount of Portland cement concrete waste that is wasted on and off the right-of-way. 

Large accumulation of Portland cement concrete waste can cause high pH runoff in the range of 11 to 12.  Runoff with a pH of 12.5 is considered a hazardous waste.  Uncontrolled disposal of Portland cement concrete waste can cause significant environmental degradation in the ground water and surrounding water bodies. 

The potential for environmental problems are a function of the availability of water, geometry of the flow net, permeability of the material, and the distance to a water body or ground water.

To minimize these potential future environmental problems, the specifications have been changed.  In 105.17, the following is required (see Figure 105.17.A):

·         Mixing of the inner core of the Portland cement concrete waste with at least 30 percent soil. 

·         Covering the mixed Portland cement concrete waste with 3 feet (1 m) of soil on the top and 8 feet (2.4 m) on the sides.

·         Placing and compacting the Portland cement concrete waste according to 203.06.D.

Figure 105.17.A Typical Drawing of the Wasting of Portland Cement Concrete Waste

106 Control of Materials

Control of materials is a necessary and important part of every construction project. The intent is to ensure that only quality (specification) materials are incorporated into the work. The Contractor must order materials sufficiently in advance of related work to allow enough time for sampling and testing. The Contractor must identify the project and the specification item number on all material orders which are defined in the construction and material specifications. The specification provides the item which references the appropriate material specification (Section 700).  The material specification is used in conjunction with the material sampling and testing program manual to provide the proper procedure for material acceptance. Additional information may be found on the material code screen on SiteManager.

The following examples identify the different methods of accepting materials on the project and methods of testing acceptance.

·         Physical sample from the project which would require no additional information.

o    Cable, curing compound.

·         Electronic TE-24, material comes from pretested stock.

o    Concrete pipe, guardrail, fence bolts.

·         Pre-qualified or pre-approved list for pre-qualified materials:

o    Concrete sealers, Epoxy, Silane, functional alternates RPMS, and adhesives.

·         Material from brand name sources:

o    Loop detector sealant.

o    Trowelable mortar.

o    Caulk for OZEU.

o    Loop detector slot sealant SS 1048.

o    Cable splicing kit.

·         Materials from manufacturers’ certified test data:

o    Section 712.09, filter fabric Type D.

·         Material accepted on letter of certified test data:

o    Water line AWWA cert., Proposal 516 517 Proposal Note, 518.

·         Physical sample and certified test data:

o    Reinforcing steel.

·         Visual inspection:

o    Dumped rock, mulch

·         Acceptance of proprietary items:

o    Impact attenuator G.R.E.A.T.

·         Catalog cuts and shop drawings:

o    Electrical, traffic control items.

General

Control of Material (106) provides that all materials are to be inspected, tested, and in compliance with the specifications prior to incorporation in the work.  Minimum requirements for sampling materials are given in C&MS Section 700, Material Details.  Samples of materials taken to meet these requirements are called job control samples.  Job control samples also include samples taken as judged necessary to determine continued compliance of materials previously approved.  These samples always represent a definite quantity of material. 

Advance notice by the Contractor of the intended source of supply for specified materials is required to permit sampling and testing of the materials.  Evidence of the approval of the materials by the Laboratory is required.

The purpose of material sampling and testing and construction inspection is to determine that only approved materials are used and that the materials are processed and placed in accordance with all contract provisions.  Systematic record keeping is necessary to furnish documented evidence that this has been accomplished.  The minimum requirements for the necessary records are stated under the individual items of work covered in this section of the manual. 

The administration of the unit price contract requires the determination of pay quantities.  The contract states the method of measurement for each item of work and it is very important that each pay quantity determination be adequately documented.

Material Documentation Process

The District Construction Administrator will determine the extent of application of responsibilities for material compliance based on project staffing level and/or expertise. It may be applied on either a wholesale or project-by-project basis.

The Engineer may approve certain materials as listed below and may modify the project bill of materials. Materials that may be approved include:

·         Any materials that are on approved or pre-qualified lists.

·         Materials for which there are approved catalog cuts.

·         Proprietary materials.

·         Temporary applications.

·         Materials that require visual inspection only.

·         Materials under the control of the Office of Structural Engineering.

·         Any materials accepted as "small quantities" per Section 106.03.

The District Testing Engineer/Test Lab will perform the following functions:

·         Sample, test, review, and authorize samples for which the Engineer does not have the authority to approve.

·         Provide staff advice to Engineer concerning material requirements.

·         Perform independent reviews of material certifications by Engineer using current guidelines for documentation of final quantities.

·         Perform quality assurance reviews on active construction projects to ensure compliance with material approval requirements.

The material certification for the projects will be approved by the District Construction Administrator.

Procedures

SiteManager will be used to document material requirements.

·         Materials approved by Engineer.

o    Project personnel will complete appropriate documentation (TE 30, etc.) create sample IDs and assign materials to the proper reference numbers.

o    The Engineer must review and authorize/approve all samples.

·         Materials approved by District Testing Engineer or the Office of Materials Management.

o    Project personnel will complete appropriate documentation (TE 31 physical sample), create sample ID's, and assign material to appropriate reference numbers.

o    The Engineer must review all documentation for completeness, sign forms, and forward paperwork or physical samples to the District Lab.

o    The District Testing Engineer or the Office Materials Management, as appropriate, will review the documentation or conduct testing of samples and authorize materials.

·         Certification of Project Materials:

o    As final quantities are determined, the Engineer, using the C&MS, will ensure that the contract and material requirements are met.

o    After all final quantities and material issues are resolved, the Engineer will complete and sign the Material Certification Letter and forward it along with the final quantities list to the District Documentation Review Team.

o    The District Testing Engineer, in conjunction with the Documentation Team, will perform a review of the material requirements using the same guidelines as required for final quantities.

o    A final certification letter will be prepared and signed by the District Highway Administrator. This letter will be directed to the Division Administrator of the Federal Highway Administrator for Non-Certification Acceptance Projects (CAP) or to the project file for all other projects.

Quality Assurance Reviews

Personnel from the District Test Lab will conduct quality assurance reviews during the actual construction phase of projects. These reviews will ensure that Project Engineers are following the policies and procedures for material approvals and identify material deficiencies while corrective action is still possible. The Division of Quality and Human Resources will establish guidelines for performance of the quality assurance reviews.

Unacceptable Material (106.07)

In the event that unacceptable materials are incorporated into the work, these materials must be monitored to determine if they will function properly in the judgment of the Engineer. If so, the Engineer must follow the process to modify the contract to allow these materials to remain in place. See Non-Specification Material Supplement.

Delivered Material

All materials must be approved prior to invoice payments and all material must be inspected at the stock piled location. All materials being used are subject to inspection or tests at any time during preparation or use. Any material which has been tested and accepted at the source of supply may be subjected to a check test after delivery or a minimal visual inspection.

Samples, Tests, and Cited Specifications (106.02)

Flexible Pavement

The term flexible pavement, used throughout this manual, includes pavement or surfacing material construction composed of asphalt material and aggregate mixtures or various combinations of layers of these mixtures on layers of aggregate base or subbase.  Although designs may vary in the combination of these materials, flexible pavement functions in a definite manner under traffic loads.  It is the intent of the design that deflection of the pavement, in reaction to wheel loads, will not stress the materials to the point of fracture within the reasonable life expectancy of the pavement.

Except for chip seals and other surface treatments, the strength of all flexible pavement layers, including subgrade, is dependent upon the density of the material and the gradation of the particle sizes.  In addition, the strength of the subgrade and granular base material is dependent on moisture content, and the strength of asphalt mixtures is partially dependent on the quantity and viscosity of the asphalt material.  While the strength of granular base materials is less affected by moisture content than soil subgrade material, adequate drainage of this material is necessary to prevent saturation of soil subgrade material and loss of subgrade strength.

All flexible pavement courses, except microsurfacing, etc., are placed loose by means of spreading and leveling equipment and then compacted with compaction equipment.  The typical sections or other plan details specify the width and thickness of the individual courses.  For granular subbase and base courses, the thickness shown in the plans is the actual compacted thickness to which the course is to be constructed.  Normally, the thickness specified for all other courses is to be used to calculate a weight of material to be placed per unit of area.

Aggregate

Aggregate may be hauled to the paving site from approved stockpiles located at the source, on the project, or at some intermediate storage point.  In any case, it is necessary to maintain sufficient surveillance to ensure that loading is from approved stock and that identity of the stockpile is not altered by addition of material or other cause.  It also is necessary to inspect the aggregate for uniformity as it is being loaded or placed.  When such observations are made, they should be recorded for the project record.

Aggregate Stockpiling

Two fundamental requirements are included in 703.01 for aggregate stockpiles: separate identity and freedom from contamination.  In addition to these considerations, knowledge of the method used in constructing the stockpile is necessary to have an understanding of the characteristics of the material as it is drawn from the pile for use.

The characteristic of an aggregate most affected by the method of stockpiling is its gradation.  The larger size aggregate particles have a tendency to separate from the smaller size particles in parts of the stockpile; this is called segregation.  A reduction in aggregate particle size can occur due to breakage or wear; this is called degradation.

Segregation is more likely to occur in an aggregate having a relatively large particle size range from coarse to fine.  The amount of segregation of aggregate particle sizes usually depends on the degree of freedom the aggregate has to flow from one place to another during stockpiling or handling.  Usually, segregation is minimized when the stockpiles are formed by placing the aggregate in successive small mounds or layers.  Small pockets of segregated aggregate are not objectionable in the stockpile, when re-mixing occurs in the loading and spreading operations, resulting in a uniform appearance.  However, when these pockets are sufficiently large that non-uniform areas can be observed in the material placed on the grade, the results are unsatisfactory, and corrective measures ensuring uniform material in place are required.

Degradation of an aggregate may occur during stockpiling due to the action of hauling and spreading equipment operating on the stockpile.  Aggregate particles may be broken into smaller sizes by heavy compressive forces exerted by such equipment.  Also, excess fine particles may be produced by interparticle abrasion caused by repeated application of these forces.  Normally, however, degradation is severe only in the case of very brittle or very soft aggregate particles.

Liquid Asphalt Materials

The Laboratory maintains a certification program throughout the year with all participating liquid asphalt material producers.  Reference should be made to Supplement 1032 regarding forms used for identification of loads from approved stock.  Loads arriving without proper identification are not to be used until specification compliance can be determined.

Since liquid asphalt materials may become contaminated and errors in shipment may occur, it is necessary to observe the delivered materials.  Where there is a question concerning the quality of the material, the Contractor should be notified and a check sample should be taken.

Asphalt Concrete

The quality control of an asphalt concrete mix is performed by the Contractor in accordance with 401.02, 441, and/or 442.

Sources of Additional Information and Guidelines for the Control and Conduct of the Work

·         Standard Operating Procedures.

o    Standard Operating Procedures (SOPs) are technically focused, unit specific procedures which affect the management and operation of specific divisions and offices of the Department, with references to technical manuals and other procedural documentation used by the various operating units.

·         Supplemental Specifications.

o    These are detailed specifications which supplement or supersede the specification sections in the C&MS.

·         Manual of Procedures and other technical bulletins.

o    Manual of Procedures (MOP) are to provide construction personnel with information necessary to control the work to be performed in accordance with the requirements of the contract, the measurement of quantities for payment, and the documentation of compliance and measurements.

·         Standard Drawings.

o    The Department furnishes Standard Drawings which provide specific details on various aspects of construction on ODOT Projects.

107 Legal Relations and Responsibility to Public

107.01 Laws to be Observed

General

Federal Contracts

The Davis-Bacon Act, 40 U.S.C. 3142 et seq., as amended, requires that each contract over $2,000 to which the United States or the District of Columbia is a party for the construction, alteration, or repair of public buildings or public works shall contain a clause setting forth the minimum wages to be paid to various classes of laborers and mechanics employed under the contract. Under the provisions of the Act, contractors or their subcontractors are to pay workers employed directly upon the site of the work no less than the locally prevailing wages and fringe benefits paid on projects of a similar character. The Davis-Bacon Act directs the Secretary of Labor to determine such local prevailing wage rates.

In addition to the Davis-Bacon Act itself, Congress has added prevailing wage provisions to approximately 60 statutes which assist construction projects through grants, loans, loan guarantees, and insurance. These "related Acts" involve construction in such areas as transportation, housing, air and water pollution reduction, and health. If a construction project is funded or assisted under more than one Federal statute, the Davis-Bacon prevailing wage provisions may apply to the project if any of the applicable statutes requires payment of Davis-Bacon wage rates.

The geographic scope of the Davis-Bacon Act is limited to the 50 States and the District of Columbia. The scope of each of the related Acts, however, is determined by the terms of the particular statute under which the Federal assistance is provided. For example, Davis-Bacon prevailing wage provisions would apply to a construction contract located in Guam or the Virgin Islands funded under the Housing and Community Development Act of 1974, even though the Davis-Bacon Act itself does not apply to Federal construction contracts to be performed outside the 50 States and the District of Columbia.

State Contracts

Ohio Revised Code Chapter 4115 requires prevailing wages be paid on state funded public improvement projects that reach the threshold level for the project.  Thresholds are adjusted biennially by the Director of the Ohio Department of Commerce and can be found on the ODOT’s prevailing wage webpage.

EEO Contract Compliance/External Civil Rights

Authority

The authority for the administration of the contract compliance program is governed by the following Federal and State Codes and Executive Orders.  Ohio Administrative Code, 123:2 “Division of EEO for Construction,” Chapters 1 through 11 (Duties, Affirmative Action program, Compliance Reviews, Hearing, Monthly Reports and Certificate of Compliance); Ohio Administrative Code, 123:2-3-05 “Required Utilization Analysis and Goals”; United States Code, Title 23: Highways, Chapter 1: Federal-Aid Highways, Section 140 (a)   Equal Employment Opportunity; Code of Federal Regulations, Title 23: Highways, Part 230: External Programs, Subpart A:  Equal Opportunity of Federal and Federal-Aid Construction Contracts (including supportive services); Code of Federal Regulations, Title 23-Highways, Chapter 1: Sub-chapter C-Civil rights,   Part 200-Title VI, Program and Related Statutes–Implementation and Review Procedure; Code of Federal Regulations, Title 23-Highways, Chapter 1: Part 230-External Programs, Subpart D–Construction Contract Equal Opportunity Compliance Procedures; Code of Federal Regulations, Title 29, Part 1608--Affirmative Action Appropriate Under Title VII of The Civil Rights Act Of 1964, As Amended; 49 CFR, Part 26; and FHWA Federal Circular PR 1273 & PR 1316.

Definitions

Administering Agency

Any department, agency and establishment in the executive branch of government, including and wholly owned Government corporation, which administers a program involving federally and State assisted construction contracts.

Affirmative Action

The efforts exerted toward achieving equal opportunity through positive, aggressive, and continuous results oriented measures to correct past and present discriminatory practices and their efforts on the conditions and privileges of employment.  These measures include but are not limited to recruitment, hiring, promotion, upgrading, demotion, transfer, termination, compensation, and training.

A good faith effort to eliminate past and present discrimination in all federally assisted programs, and to ensure future nondiscriminatory practices.

Apprentice

(i) A person employed and individually registered in a bona fide apprenticeship program registered with the U.S. Department of Labor, Employment and Training Administration, Office of Apprenticeship Training, Employer and Labor Services, or with a State Apprenticeship Agency recognized by the Bureau, or (ii) A person in the first 90 days of probationary employment as an apprentice in such an apprenticeship program, who is not individually registered in the program, but who has been certified by the Office of Apprenticeship Training, Employer and Labor Services or a State Apprenticeship Agency (where appropriate) to be eligible for probationary employment as an apprentice.

Apprentice Permit

"Apprentice permit" means a permit issued by the Union to authorize a person desiring to achieve journey-person status to obtain skilled craft experience under supervision of a full journey-person.

Apprenticeship Program

A bona fide training program, registered with the Ohio State Apprenticeship Council, aimed at developing the skill level of a person until the person reaches full journey-person status (generally four years).  The training includes both school and hands on study of the craft.

Area-wide Plans

An Affirmative Action plan to increase minority utilization of crafts in a specified geographical area pursuant to “Executive Order 11246" or taking the form of an “Imposed” Plan.

Area workforce

Employees at all Federal-Aid, Federal or non-Federal projects in a specific geographical area as determined under CFR 23; Part 230.409(b)(9).

Bid Conditions

Contract provisions, which have been issued by the Ohio Department of Transportation, Office of Contracts.                                    

Commercially Useful Function

A Disadvantaged Business Enterprise (DBE) performs a commercially useful function (CUF) when it is responsible for execution of the work of the contract and is carrying out its responsibilities by actually performing, managing, and supervising the work involved.  To perform a CUF the DBE must also be responsible, with respect to material and supplies used on the contract, for negotiating price, determining quality and quantity, ordering the materials and installing (where applicable) and paying for the material itself.

Compliance

The condition existing when a contractor has implemented all of the standards set forth in the applicable rules and regulations governing equal opportunity and affirmative action laws of State and Federal government.

The satisfactory condition existing when a recipient has effectively implemented all of the Title VII requirements or can demonstrate that every good faith effort toward achieving this end has been made.

Conciliation Agreement

Agreement arrived by the Reviewing agency and the contractor, which outlines steps the contractor will take to bring his/her firm into compliance.

Construction Work

The construction, rehabilitation, alteration, conversion, extension, demolition, or repair of buildings, highways, or other changes or improvements to real property, including facilities providing utility services.  The term also includes the supervision, inspection, and other onsite functions incidental to the actual construction.

Contract

Any Federal or State assisted construction contract.

Contractor

Any person, corporation, partnership, or unincorporated association that holds a Federal or State assisted construction contract or subcontract regardless of tier.

Contractors’ Workforce

All employees on the payroll of and who are directly supervised by the contractor.

Corrective Action Plan

A contractor’s unequivocal written and signed commitment outlining actions taken or proposed within the time limits and goals, where appropriate to correct, compensate for, and remedy each violation of the equal opportunity requirements as specified in a list of deficiencies.

Disadvantaged Business Enterprise (DBE)

Small business as defined in “Appendix B” of Subpart D, Part 23, Title 49, Code of Federal Regulations, which is owned and controlled by persons who are citizens or lawful permanent residents of the United States, and who are members of a disadvantaged group including Black Americans, Hispanic Americans, Native Americans, Asian-Pacific Americans, and other individuals found on a case by case basis to be socially and economically disadvantaged.

Discrimination

A distinction in the treatment of a person based on race, color, religion, sex, national origin, age (40-70 years), or disability.

The act (or action) whether intentional or unintentional through which a person of the United States, solely because of race, color, religion, sex, or national origin, has been otherwise subjected to unequal treatment under any program or activity receiving financial assistance from the Federal Highway Administration under Title 23 U.S.C.

District Equal Employment Opportunity Contract Coordinator (DEEOCC)

A Federal or State employee regularly employed and experienced in civil rights policies, practices, procedures, and equal opportunity compliance review and evaluation functions.

Documentation

Those records and reports maintained by the contractor to verify claims relative to employees, payroll, subcontractors, etc.

Equal Employment Opportunity

The absence of partiality or distinction in employment treatment, so that the right of all persons to work and advance on the basis of merit, ability and potential is maintained.

Equal Opportunity Clause

The contract provisions set forth in CFR Chapter 60-1.4(a) or (b), as appropriate.

Equal Opportunity Compliance Review

An evaluation and determination on non-exempt direct Federal, Federal-Aid or State contractor, or sub-contractor’s compliance with equal opportunity requirements based on:

Equal Opportunity Requirements

A general term used throughout this document to mean all contract provisions relative to equal employment opportunity (EEO), sub-contracting and training.

FHWA

Federal Highway Administration

Fringe Benefits

Includes medical or hospital care, pensions on retirement or death, compensation for injuries or illness resulting from occupational activity, or insurance to provide any of the foregoing: unemployment benefits, life insurance, disability insurance, sickness insurance,  accident insurance, vacation or holiday pay.  Also includes defraying costs of apprenticeship or other similar programs or other bona fide fringe benefits. Fringe benefits do not include benefits required by other federal, state, or local law.

Good Faith Effort Deficiency

A contractor may be found in noncompliance when compliance review findings indicate that good faith effort actions taken, or lack thereof, by the contractor have not resulted in the employment of minorities and females in the workplace.

Good Faith Effort

Affirmative action measures designed to implement the established objectives of an Affirmative Action Plan.

Home Office Workforce

Employees at the physical location of the corporation, company, or other ownership headquarters or regional managerial offices, including “white collar” personnel (managers, professional, technicians and clerical) and any maintenance of service personnel connected thereto.

Imposed Plan

An affirmative action requirement for a specified geographical area made mandatory by OFCCP, and in some areas by the courts.

Journeyman

A person who is capable of performing all the duties within a given job classification or craft.

Local Public Agency (LPA)

Any other State agency, local political subdivision, board, commission, or other governmental entity identified under paragraph C of section 5501.03 of the Ohio Revised Code (ORC) determined to be qualified to assume the administrative responsibilities for Ohio Department of Transportation (ODOT) improvements projects.

Minority

A person who is a citizen or lawful permanent resident of the United States, and who is Black, Hispanic, Pacific Islander, Asian American, Native American or Alaskan Native.

New Hires

An individual who has a break in service (not on an employer’s payroll) for a period of 12 months or longer and the person affected is not a salaried employee, but belongs to a union craft.  Individuals compensated for training or incidental work which does not cause a break in unemployment compensation, i.e., paid by voucher check or petty cash, are considered new hires

if the individual’s break in service is 12 months or longer.  The time frame for a new hire shall be associated with the first project worked for that contractor regardless of whether it is public or private. When reporting new hires the contractor shall identify

that employee as a new hire on that specific project only. Subsequent work, barring a break in service of 60 days or more, would not qualify the employee as a new hire for that contractor.

Noncompliance

The condition existing when a recipient of federal or state funds or a contractor working on a state or federally funded project has failed to show good faith efforts to implement the requirements of the equal employment opportunity and affirmative action laws.

A recipient who failed to meet prescribed requirements and has shown an apparent lack of good faith effort in implementing the requirements of Title VII.

On-The-Job-Training

A program that includes the training and upgrading of minorities and females toward journey-person status.

Paper Deficiency

Any deficiency which can be corrected and verified by the reviewer within 10 days of the Exit Conference (i.e., EOE tagline, EEO/Sexual Harassment policy corrections).

Permit Person

A person signed with the Union who receives full benefits, but is in pre full member status, earning journeyman’s wages working for a specific time period (generally 78 weeks) after which the permit person is sold full membership. 

Persons/Protected Class

Where designation of persons by race, color, national origin is required, the following designations ordinarily may be used:  "Black Americans," which includes persons having origins in any of the Black racial groups of Africa; "Hispanic Americans," which includes persons of Mexican, Puerto Rican, Cuban, Dominican, Central or South American, or other Spanish or Portuguese culture or origin, regardless of race; "Native Americans," which includes persons who are American Indians, Eskimos, Aleuts, or Native Hawaiians; "Asian-Pacific Americans," which includes persons whose origins are from Japan, China, Taiwan, Korea, Burma (Myanmar), Vietnam, Laos, Cambodia (Kampuchea), Thailand, Malaysia, Indonesia, the Philippines, Brunei, Samoa, Guam, the U.S. Trust Territories of the Pacific Islands (Republic of Palau), the Commonwealth of the Northern Marianas Islands, Macao, Fiji, Tonga, Kiribati, Tuvalu, Nauru, Federated States of Micronesia, or Hong Kong;

"Subcontinent Asian Americans," which includes persons whose origins are from India, Pakistan, Bangladesh, Bhutan, the Maldives Islands, Nepal or Sri Lanka.

Preconstruction Meeting (Precon)

This meeting attended by the Prime Contractor and ODOT personnel is for a discussion of the details on constructing the project, bid proposal, specifications, plans, method of payment, and the Prime Contractor’s progress schedule.

Prevailing Wages

Means the basic hourly rate of pay, any contribution irrevocably made by a contractor or subcontractor to a trustee or to a third person pursuant to a bona fide fringe benefit fund, plan, or program, and the rate of costs to the contractor or subcontractor which may be reasonably anticipated in providing bona fide fringe benefits to laborers and mechanics pursuant to an enforceable commitment to carry out a financially responsible plan program, which was communicated in writing to the laborers and mechanics affected. Prevailing Wage Exemptions: The following work types are exempt from the payment of prevailing wages: mowing, herbicidal spraying, trash pick-up in maintenance yards, center line survey, sign inventory, tree trimming and tree removal (with no construction to follow).

Project Workforce

Employees at the physical location of the construction activity.

Show-cause Notice

A written notification to a contractor, based on the determination of the reviewer (or in appropriate cases by a higher level authority), that the contractor is in noncompliance with the equal opportunity requirements.  The notice informs the contractor of the specific basis for the determination and provides the opportunity with 30 days from the receipt to present an explanation as to why sanctions should not be imposed.

Site of Work

The physical place or places where the building or work called for in the contract will remain and any other site where a significant portion of the building or work is constructed, provided that such site is established specifically for the performance of the contract or project. Job headquarters, tool yards, batch plants, borrow pits, etc., are part of the site of the work, provided they are dedicated exclusively, or nearly so, to performance of the contract or project and provided they are adjacent or virtually adjacent to the site of the work.

Not included in the site of the work, are permanent home offices, branch plant establishments, fabrication plants, tool yards, etc., of a contractor or subcontractor whose location and continuance in operation are determined wholly without regard to a particular Federal or federally assisted contract or project. In addition, fabrication plants, batch plants, borrow pits, job headquarters, tool yards, etc., of a commercial or material supplier, which are established by a supplier of materials for the project before opening of bids are not on the site of the work.  Such permanent, previously established facilities are not part of the site of the work, even where the operations for a period of time may be dedicated exclusively, or nearly so, to the performance of a contract.

Trainee

A person who receives on-the-job training, whether through an apprenticeship program, or other programs approved or accepted by the Federal Highway Administration, and/or the appropriate State agency.

Unified Certification Program (UCP)

The UCP is a unified directory including all certified DBE firms who are available for the entire State of Ohio. The main advantages for the DBE firms are: one certification will enable them to be eligible to fulfill DBE goals set on any project with any governmental agency receiving Federal Transportation funding in Ohio; and the DBE firms will also have more visibility due to the unified state-wide directory.

Virtually Adjacent

The Federal regulations do not define what is considered “virtually adjacent”.  However, the Ohio Department of Transportation has determined that all work areas located within a 1-mile radius of the project site will be considered to be virtually adjacent.

Prevailing Wage

Central Office Duties

The Division of Construction Management shall ensure uniform administration of applicable prevailing wage requirements by the various districts, and perform the following functions:

A.      Provide liaison between the Department, and Department of Commerce Wage and Hour (DOCWH) and USDOL;

B.       Advise districts of any changes in prevailing wage laws, and aid in the resolution of any wage related problems;

C.       Provide training on prevailing wage enforcement to the District Prevailing Wage Coordinator (DPWC);

D.      Conduct Technical Process Reviews (TPRs) of District compliance with prevailing wage laws, regulations, and policies. These reviews should be conducted once every two years for each District;

E.       Prepare the Semi-Annual Labor Compliance Enforcement Report;

F.       Maintain a current list of DPWCs and provide it to Ohio Department of Commerce (ODOC) and USDOL;

G.      Monitor district field operations.  This should include a visit to each District at a minimum of once a year.  Additional visits may be required as circumstances may dictate. (ex. ongoing wage investigations);

H.      The Division of Construction Management will hold a statewide DPWC training meeting, twice a year, to review and ensure understandings of prevailing wage enforcement procedures, policies, regulations, and laws.  In addition, the Division of Construction Management will provide individual training to district personnel when requested.

District Duties

Reporting Requirements

Semi-Annual Labor Enforcement Report

Required Pursuant to Section 5.7 (b) of Regulation, Part 5 covering the time period of April 1st through September 30th and October 1st through March 31st.   This report is due to Central Office on or before October 20th and on or before April 20th.  The report is due to FHWA on or before October 31st and on or before April 30th.

Monthly Prevailing Wage Enforcement Report

Due by the 7th of the following month.  The report contains the following items: district, date, prevailing wage coordinator, report month, number of projects currently working, number of on-site visits conducted, number of investigations completed/ongoing and the date, project number, project location, contractor name, number of employees involved, wage complaints and action or resolution for each investigation is listed.

Wage Classifications

Wage rates for Federal-aid projects are determined by the Secretary of Labor in accordance with Federal-aid requirements.  Contractors shall use only the classifications set forth in the contract on payrolls submitted to the District Office.  Wage and fringe payments for each classification shall be in accordance with the U. S. Department of Labor Regulations, Title 29, Subtitle A, Part 5, Sections 5.5, 5.31 and 5.32 and Form FHWA-1273 Part IV.  If the contractor must use a classification not listed in the contract, said classification must be added to the contract. 

The procedure for requesting additional classifications is as follows:

A.      The District Prevailing Wage Coordinator will require the prime/sub-contractor to complete federal Standard Form 1444 detailing the work classification to be added to the contract.  Standard Form 1444 can be found at web site:  www.dol.gov/whd/contracts/dbra.htm

B.       Prime contractor should have all interested parties sign the request.  This includes the subcontractor (if applicable) and the employee affected or a union representative who can list the proper classification and wage for the work being performed. 

C.       Prime contractor returns the form along with any supporting documentation to the District Prevailing Wage Coordinator for final review and signature.  The District Prevailing Wage Coordinator submits the form to:

                                Administrator, Employment Standards Administration

                                Wage and Hour Division

                                U. S. Department of Labor

                                Washington, DC 20210.

Requests take approximately 30 days to process.  In the meantime, the contractor should pay a reasonable rate for the work being performed. Supporting documentation should include a detailed description of the work being performed, the equipment being used and the union classification covering the work, if available.

Site Visits

The District Prevailing Wage Coordinator is responsible for visiting the projects in his/her area on a regular basis.  These project visits are conducted primarily as a tool to “spot check” the prime and subcontractors for prevailing wage compliance, as well as responding to a complaint or problems found on submitted payrolls.

The District’s minimum monitoring schedule shall be based on the duration of the project as follows:

Actual Project Duration

Minimum Required Site Visits

Less than two months

1

Two or more months

Every other month beginning with the first month

It should be noted that this is a minimum requirement for monitoring.  Circumstances may dictate that more site visits be required on a particular project.

All interviews shall be conducted using the Standard Interview Form that is located on the ODOT Central Office Prevailing Wage Website. Copies of the completed interview forms for each interview performed should be included in the DPWC’s project file.

Wage Complaints

When a valid wage complaint is discovered or received, documentation is the key element to a successful resolution.  If the matter is not resolved, this documentation is the beginning of the paper trail for either the U.S. Department of Labor or the Department of Commerce Wage and Hour.  In the event of a wage complaint from an employee, it is important to have the following items in the file:

A.      The employee’s formal statement detailing the complaint;

B.       Any check stubs that the employee has provided;

C.       Any on-site reviews that may have been conducted on the subject project;

D.      Copies of the Daily Diaries in Site Manager;

E.       Copies of any communication to the prime contractor regarding the possible violations.

It is also important to keep the employee’s name confidential as long as possible, so that the employee is not subjected to retaliation. 

Wage Violations

Discrepancies and/or Underpayments on the Payrolls

Some underpayments and other errors can appear on the face of the payroll (i.e., do not involve falsification). In these cases, DPWC will contact the employer and/or the prime contractor and provide instructions as to what steps should be taken to correct the payroll and to pay any back wages that may be due to the affected workers.

Indications of Falsification on Payrolls

Information reported on payrolls that indicate willful falsification suggests much more serious violations in terms of the amount of back wages that may be due and the number of employees affected. Such cases most often warrant investigation which can include on-site interviews with the workers, mailing questionnaires to employees, taking written statements or complaints, and other methods to gather and assess the facts of the case.

In the event that a wage violation that indicates falsification is found or reported, the following procedure shall be followed:

A.      Send a letter to the prime contractor with a copy to the Central Office Prevailing Wage Manager explaining the violations discovered.

1.        If the violation involves an incorrect rate, the correct rate(s) must be listed with the total amount of money due to each employee.

2.        If the violation involves incorrect fringes that are owed to the union, the correct amount owed to the union must be listed for each employee.

3.        If the violation involves a discrepancy in the number of hours paid to an employee, the correct number of hours must be determined through review of inspector diaries, project supervisor records, on-site interviews, or any other relevant documentation.  The corrected hours must be listed with a total amount due for each employee.

4.        If the violation involves a misclassification issue, each employee in dispute must be listed with the work that he/she performed, the date(s) in question, the proper classification, and correct rate of pay.

B.       The prime contractor must be given a date to respond to the allegations (2 weeks is recommended).  The response from the prime contractor to the District Office may include corrected payrolls or other documentation.

C.       If the corrections require additional payments to employees, the payment amounts to each employee shall be approved in advance by the District Office and the District Office will coordinate the payments to each employee.  The District Office must copy Central Office on all communications between the Contractor(s) and the District Office. These additional payments shall be in the form of checks cut by the appropriate contactor (either prime or sub) to each employee and sent to the District Office for distribution.  Once received, the District Office will make copies and distribute the checks by one of the following methods: (a) certified mail w/ return receipt requested (b) employee pick-up at the District Office with signature of receipt or (c) hand delivery with a signed receipt by the District.  In the event the investigation involves multiple districts or is being handled by Central Office directly, the payments will be sent to Central Office.  The Prime Contractor will be required to provide a copy of the cancelled checks when they become available.  Once these copies are received, a letter will be generated to the Prime Contractor informing them of the successful completion of ODOT’s investigation.  If the Prime Contractor or its sub-contractor is not cooperative during the investigation or is a repeat offender of similar violations, Central Office will evaluate any further sanctions against the contractor.

D.      If the Prime Contractor does not respond to the letter from the District Office, the money must be withheld from the next project estimate.  Another letter must be sent out to the Prime Contractor with a copy to the Central Office Prevailing Wage Manager immediately explaining the reason for the withholding.  If there are no remaining funds to withhold, monies may be withheld from any other federal project that the Prime Contractor is working.  However, this can only be done with prior approval from Central Office.

E.       If a response is not received after a withholding of funds, the matter should be turned over to Central Office to evaluate further sanctions against the contractor (See federal circular 1273).

Wage Modifications

Wage Modifications are made to state funded projects.  Notification of these modifications must be made within 7 days of receipt from the Department of Commerce.  Failure to do so obligates ODOT for the payment of back wages.

State Funded projects are subject to changes in the prevailing wage rates throughout the duration of a project.  The following is the order in which the Wage Modifications are dispersed: 

A.      The Wage Change notifications are sent to all Prevailing Wage Coordinators by e-mail from the Department of Commerce, Wage and Hour.

B.       After receipt of the notification, the Wage Coordinator will then go to the Wage and Hour website:

(http://wagehour.bes.state.oh.us/w3/webwh.nsf?Opendatabase),

Download and print the corresponding rates.

C.       Modifications are e-mailed out to the affected prime contractors on all state funded projects with instructions to notify all of their subcontractors.  A copy is kept for the office file and a copy is sent to the Project Engineer/Supervisor.

D.      The modifications must be mailed within 7 working days after the receipt of notification.

E.       The modified rates shall be posted on the project bulletin board.

F.       The contractors’ certified payrolls shall be checked against the modified rates when they become effective.

Withholding Project Estimates

When a contractor fails to provide documentation such as Certified Payrolls, or has not paid an employee(s) the correct wages, it may become necessary for the District to withhold money from the project estimate to cover any possible deficiencies.  The ODOT is authorized to withhold project estimates according to 29 CFR Subtitle A, §5.5(3) and 5.9. Central Office will require the Districts to take the following actions with regards to withholding money from project estimates:

A.      Delinquent Wages: Withhold an amount equal to that owed to an employee(s), plus 100%, until restitution has been made.

B.    Delinquent Payrolls: Withhold the estimated amount of the payroll, plus 100%.  Continue to withhold this estimated amount, until the delinquent payrolls have been received.

C.    Unapproved Subcontractors: Withhold 100% of the money for the work type(s) performed by that subcontractor, until a valid C92 is in place, and the Supplemental Payrolls have been submitted.

Written notice must be provided to the contractor prior to withholding any funds.

The following contract provision is required for Federal-aid construction contracts:

                Withholding:

The SHA shall upon its own action or upon written request of an authorized representative of the DOL withhold, or cause to be withheld, from the contractor or subcontractor under this contract or any other Federal contract with the same prime contractor, or any other Federal-assisted contract subject to Davis-Bacon prevailing wage requirements which is held by the same prime contractor, as much of the accrued payments or advances as may be considered necessary to pay laborers and mechanics including apprentice, trainees, and helpers, employed by the contractor or any subcontractor the full amount of wages required by the contract.  In the event of failure to pay any laborer or mechanic, including any apprentice, trainee, or helper, employed or working on the site of the work, all or part of the wages required by the contract, the SHA contracting officer may, after written notice to the contractor, take such action as may be necessary to cause the suspension of any further payment, advance, or guarantee of funds until such violations have ceased.

Certified Payrolls

Certified payrolls are required to be submitted by all prime contractors for the prime contractors and their subcontractors, beginning with the first day of work on the project.  The contractors are required to submit their certified payrolls electronically to the following e-mail address:

certified.payrolls@dot.state.oh.us

Listed below are step-by-step instructions for processing certified payrolls, once submitted to the district via the e-mail address:

A.      Establish and maintain for each project a file of audited certified payrolls submitted by each Contractor, Subcontractor, and Vendor.

B.       Certified Payrolls can be accessed through the certified payroll SharePoint site located on the ODOT portal site.

C.       On a weekly basis, a list will be randomly generated for each district to identify the payrolls that are required to be audited by the DPWC.  This list identifies the minimum number of payrolls that are required to be audited; however, circumstances may dictate that more payrolls require an audit (ex. wage investigation, etc.).

D.      Check and ensure that payroll certificate of compliance is signed by the appropriate company officer or proper designee. 

E.       The name of the contracting company submitting the payroll, must be the same as on the signed contract or the awarded C-92.  For example, a parent company may not submit payrolls in its name, on behalf of a subsidiary company.

F.       Check for completeness and accuracy of the payrolls as to the names, addresses, identification number of each worker, job classifications, hourly wage rates, daily and weekly hours worked during the payroll period, gross weekly wages earned, deductions made from wages, and net weekly wages paid the employee.

G.      If the employee worked on more than one job, they are only required to show the ODOT project hours on the payroll.  The total gross wages an employee earned for the week can go above the ODOT wages, but ODOT wages must be separate.  

H.      If the Contract Work Hours and Safety Standards Act is applicable and an employee worked in excess of forty hours in any workweek, ensure that the employee was paid one and ½ times their regular rate.  Fringes are paid for the total hours worked and is not subject to time and a half.

I.         Examine certified payrolls for noteworthy discrepancies such as a disproportionate number of laborers, apprentices or helpers on the project.

J.        Check for contributions to fringe benefit plans.

K.       Check to ensure that each payroll submitted, is accompanied by a “Statement of Compliance” as required by the Copeland Act on Federal projects and the Ohio Revised Code, Chapter 4115 on State Projects.  The Statement of Compliance is passed out at all preconstruction meetings to the prime contractor with the requirement that the prime forwards to their subcontractors.  

L.       Checking the payrolls: Check wages for federal projects.  The wages in the proposal are for the duration of the project. State projects are subject to change. The wage modifications are sent to the Prime Contractor when State Wage and Hour updates and sends the changes to the Prevailing Wage Coordinator of each District.   Wage extensions - periodically check the contractors’ extension for each craft.  Classifications are to be broken down on payrolls, Group 1-5 or type of equipment operating for each employee.  Check for apprentice’s and laborer trainees.  All apprentices have to be registered with the The Ohio State Apprenticeship Council (“OSAC”) and have an “Apprentice Certification”. The Apprenticeship Agreement Form from the Union is not acceptable.  If the employee is not a “Certified Apprentice” he or she must be paid full Journeyman’s wages.

M.     Spot check against the Project DWR located on the Sharepoint Site to determine if the hours and classifications reported matches the projects records of work performed during the period.

N.      Statute requires that all contractors and subcontractors must submit Certified Payrolls “not less often than once a week”.

O.      Fringes are a part of the wages.  The contractor must furnish a copy of its fringe break down for each classification.  This can go on the contractor’s letter head stationary and submitted with each payroll. All contractors are required to pay fringes in cash (via check) to the employee or a “bona fide” fringe benefit fund, plan or program that the contractor makes no direct or indirect profit.  The wages and fringes have to equal rates in the proposal. 

P.       If a working foreman spends more than 20 percent of the time performing laborer or mechanic duties at the job site, the hours spent in these activities must be paid at least the hourly rate specified in the contract wage determination for the appropriate laborer or mechanic classification(s). 

Q.      The first day of work on the project is when the trailer and/or office is set up, when signs are put up or when the electrical poles for signals for project are installed.   The first day of the payroll and the daily diary first day should match.     

Delinquent Payrolls

The following steps should be utilized when trying to obtain delinquent payrolls:

A.      Request the payrolls by phone followed by written notification, informing the prime contractor that money will be withheld from the estimate if payrolls are not received within the next week.

B.       If payrolls are not received in the stated manner, then it is the District’s responsibility to withhold money from the estimate, until payrolls are received. (see section on withholding project estimates)

C.       Each time monies are withheld, written notification should be sent to the prime contractor informing it of the situation.  If the problem is with a subcontractor, a copy of each written notification should also be sent to the subcontractor.

Bulletin Board

ODOT is required to ensure that the Project Bulletin Boards are placed at the field office and are in a location easily accessible to both the employee and the general public.  For mobile operations (i.e. guardrail or asphalt), the bulletin board information may be kept on the outside foreman’s vehicle, not inside the cab, and/or the staging area provided that the general public and all employees have safe easy access to the material.  The following is a sample of the first page of the two checklists that have been developed to assist with ensuring the proper posters are on the jobsites.  The complete checklists can be found on the Office of Contracts Website.

Pre-Construction Meetings

The District Prevailing Wage Coordinator or a designee is expected to attend all pre-construction meetings regarding the status of the project.  The District Prevailing Wage Coordinator or a designee should obtain a copy of the sign-in sheet from each meeting for documentation of attendance.

Pre-Construction Meetings are the first contact ODOT has with the contractor with respect to a specific project.  They are held prior to the beginning of a construction project, and are attended by a representative of the prime contractor, representatives of ODOT (usually an engineer), EEO, Prevailing Wage, Right-of-Way, and Project Personnel, any interested landowners, utility companies, and subcontractors.  During this meeting all expectations of the contractor are discussed along with any special issues concerning the project.

It is important during this meeting to direct the contractor to the wage rates link in the back of the proposal, all the requirements of payroll submittal and the bulletin board on the project, as well as informing the contractor that wage interviews will be taking place at the project site. Also, you must document that this information was given to the contractor in the meeting minutes.

The following items must be included in the preconstruction packet:

A.      Statement Of Compliance Form

B.       All applicable posters

C.       Prevailing Wage Guidelines Letter

D.      Blank Federal/State Payrolls

E.       Blank C-92 (optional)

F.       The posters and wages from the proposal.  The contractor is responsible for inserting the company EEO Policy and name and phone number of the EEO officer.

G.      A summary of the EEO requirements as outlined in the contract.

H.      Contractor’s guideline for participation in the ODOT OJT Program.

I.         A sample Subcontractor notification letter outlining the contract EEO requirements.

Apprentice and Trainee Requirements

The District Prevailing Wage Coordinator must perform the following functions with respect to Apprentices and/or Trainees:

A.      Review certified payrolls for apprentices on the job; 

B.       Verify that the wage paid is in compliance with the contract wage rate for the level of apprenticeship and the classification worked and that the appropriate ratios are met accordingly;

C.       Request from the contractor a copy of the apprenticeship certification (not the Union Apprenticeship Agreement).  If the contractor does not have the apprentice certification, then the employee will be paid as a full journeyman;

D.      If Apprenticeship Certification is not received within 90 days of the employee beginning work on the project, full journeyman wage will be paid the employee;

E.       The DPWC will maintain a separate file of the apprentice certification forms in the DPWC office.  A copy of the apprentice form should be included in each project file for documentation;

Administrative Closures

After a period of 2 years has elapsed since the end of a project, and the DPWC has made numerous attempts to collect the necessary payroll documentation that is required to close-out a project, an administrative closure may be necessary. The procedure for effectuating an administrative closing for both Federal and State projects is outlined below.

Federal

On federally funded projects, Central Office is to send a detailed account of the paperwork that was missing in order to close-out the project, the steps taken in trying to obtain the missing paperwork, and a summary of any monies still being held on the project.  The facts and details of the project will be submitted to Central Office, by the DPWC.  A letter is then sent to FHWA requesting permission to administratively close out the project.

State

On state funded projects, the District office is to send a detailed account of the paperwork that was missing in order to close-out the project, the steps taken in trying to obtain the paperwork, and a summary of any monies still being held on the project.  A letter is then sent to the state Prevailing Wage Manager in Central Office, requesting permission to administratively close out the project.

Local Public Agency (LPA) Projects

ODOT will be monitoring LPA projects in each District.  The ODOT will randomly check between 20-25 percent of jobs equal to or in excess of $500,000.  The District LPA Coordinator can provide information of newly awarded LPA projects.

The ODOT’s role is to provide guidance to the LPA with respect to EEO and Prevailing Wage issues.  District Coordinators are not to perform any of the functions that they typically would on an ODOT project, such as interviewing employees or collecting or reviewing Certified Payrolls. It is strongly encouraged that LPA pre-con meetings be attended in order to ensure that all pertinent information related to EEO and PW is disseminated to the appropriate contractor personnel.

Listed below are a few points that must be discussed with the LPA:

A.      Is the LPA receiving certified payrolls from the prime contractor and all subcontractors on a weekly basis?

B.       Is the LPA reviewing those payrolls for accuracy, to ensure that the correct wages are being paid to the employees?

C.       Does the LPA have apprentice certifications for all employees listed as “apprentices” on the certified payrolls?

D.      Are all posters and the company’s EEO policy displayed? 

E.       During the Pre-Construction meetings, are the contractors made aware of all Prevailing Wage and EEO requirements, and provided all necessary forms and posters?

F.       If there is a DBE goal on the project, is the DBE performing a “commercially useful function”?

G.      Is the LPA correctly crediting the DBE participation (60% for materials, trucking at 100% only when performed by DBE owned trucks)?

H.      Document the results of your visit in a report and keep these reports in a file for LPA oversight.

I.         Report any LPA deficiencies to the District LPA coordinator.

Trucking

Site of Work

Laborers and mechanics must be paid prevailing wage rates and fringe benefit rates at the site of work. Site of work is defined in the Federal code of regulations as follows.  Title 29 CFR 5.2 (l)(1) states "The site of the work is the physical place or places where the building or work called for in the contract will remain; and any other site where a significant portion of the building or work is constructed, provided that such site is established specifically for the performance of the contract or project”.

Title 29 CFR 5.2 (l)(2) states that other work areas not located on the site of permanent construction (e.g. job headquarters, tool yards, batch plants, borrow pits, etc.), may be part of the site of the work " . . . provided they are dedicated exclusively, or nearly so, to performance of the contract or project, and provided they are adjacent or virtually adjacent to the site of the work.”

The Federal regulations do not define what is considered to be “virtually adjacent”, however the Ohio Department of Transportation has determined that all work areas located within a 1-mile radius of the project limits will be considered to be virtually adjacent. Any non Owner-Operators who are hauling materials within the Site of Work as described above, are entitled to the appropriate prevailing wage rate.

Truck drivers are covered by Prevailing Wage requirements and provisions in the following circumstances:

A.    Drivers of a contractor or subcontractor for the time spent working on “the site of the work.”

B.     Drivers of a contractor or subcontractor for the time spent loading and/or unloading materials and supplies on the site of the work.

C.     Truck drivers transporting materials and supplies from a facility that is a part of the “site of the work” and the actual construction site.

Exemptions

Truck drivers who come onto a site of work location to drop off construction materials are often exempt from the payment of prevailing wages.  If however, the total of all time that a driver spends on-site (as described above), loading and unloading materials, is equal to or greater than 20% of their total work week, he or she would be entitled to the appropriate prevailing wage rate for that time. 

Owner Operators

The legal test that is utilized to determine if the owner-operator is in fact an independent contractor stems from the right to control test.  An owner-operator has the right to agree or disagree upon whether he or she chooses to work on a particular project.  The owner-operator should evidence this relationship by a written contract. 

Additionally, an owner-operator makes a significant financial commitment when he or she purchases or enters into a bona fide lease agreement.  The term of that lease must be substantial (in the proximity of 1 year or longer), and not subject to cancellation at any time. A lease agreement which simply provides the driver a percentage of revenue is not a bona fide lease agreement. In short, the financial commitment must be real.

Furthermore, the legitimate owner-operator must assume all responsibility for the maintenance of the equipment, and bears the principal burden of the operating costs such as fuel, repairs, supplies, vehicle insurance, permit fees, and personal expenses while on the road.     

Driver documentation such as a driver’s license, vehicle registration, insurance, and lease agreements will be reviewed by ODOT project personnel.  It also must be demonstrated that there is no close or continued supervision of the operation of the truck by the company leasing the truck. 

In some cases, an owner-operator has more than one truck employed on a contract and must be a subcontractor.  The other truck operators are not classified as an owner-operator and are subject to the appropriate prevailing wage rate.  

Certified payrolls, including the names of such owner-operators do not need to show the hours worked or the rates paid, only the notation “owner-operator”.  This position does not apply to owner-operators of other equipment such as bulldozers, backhoes, cranes, etc.

Equal Employment Opportunity Contract Compliance

General

Policy, Purpose and Scope

It is the policy of the Ohio Department of Transportation to require full utilization of all opportunities to assure the increased participation of minorities, females and disadvantaged persons in all phases of the highway construction industry.

Objective

The primary objective is to standardize the evaluation of the contractors’ affirmative action efforts to comply with the Code of Federal Regulations (CFR), Title 23, Part 230, and  Title 23: Highways, Chapter 1: Sub-chapter C-Civil Rights, Part 200 Title VI.

Applicability

This procedure is applicable to all Federal-Aid Highway construction projects, Appalachian Highway construction projects, and other State supervised cooperative highway construction projects.

Central Office Duties

The Division of Construction Management shall ensure uniform administration of applicable Equal Employment Opportunity (EEO) policies for ODOT’s statewide EEO contract compliance program and Disadvantaged Business Enterprise (DBE) Program as it applies to ODOT highway construction projects in accordance with Code of Federal Regulations (CFR) 23, Part 230, Subparts A-D and CFR 49, Part 26, Subparts A-F and perform the following functions:

·         Act as liaison between Central Office’s Office of Contracts and DEEOCCs and their supervisors (District Construction Administrators – DCAs).

·         Develop and implement policies and procedures to adjust and improve ODOT practices statewide as needed to comply with state and federal laws, rules, regulations and procedures as they relate to external civil rights.

·         Develop Technical process Reviews of District EEO records and work practices to provide Department-wide consistency, validate policy compliance and determine best practices. 

·         Maintain contact with DEEOCCs and appropriate construction project site employees to verify contract compliance and ensure DBE firms are performing commercially useful functions.

·         Review and process requests for partial waiver of DBE and EDGE goals on both ODOT and Local Let projects and monitor project goal attainment.

·         Serve as Local Public Agency (LPA)/DBE liaison for Office of Contracts with Office of Local Programs, Federal Highway Administration (FHWA) and District EEOCCs to ensure local entities are in compliance with federal regulations regarding LPA program-related contracting responsibilities.

·         Coordinate and provide training to DEEOCCs regarding federal EEO compliance and Departmental policies and procedures.

Responsibilities of the District Equal Employment Opportunity Contract Coordinators

The DEEOCC is responsible for executing the enforcement/compliance activities associated with EEO on construction contracts.  The DEEOCC participates in on-site inspections to determine contractor compliance under all relevant rules and regulations.  They initiate and process documents on Contract Compliance/Affirmative Action, conducting interviews both on-site and in the contractor’s office.  They attend and participate in Preconstruction, Progress and Contract Compliance review meetings.  In conjunction with District, Central Office and FHWA Division personnel, the DEEOCC conducts Compliance Reviews, reviews EEO reports, monitors Disadvantaged Business Enterprise activities, prepares ODOT reports to FHWA, and conducts investigations.  The DEEOCC attends training on EEO programs and requirements.  The DEEOCC attends workshops and uses contract documents, FHWA and State regulations, and related forms to coordinate and execute their responsibilities under the External Civil Rights Contract Compliance Program.

Specific Equal Employment Opportunities Responsibilities

The contractor and all his/her subcontractors holding subcontracts not including material suppliers, of $10,000 or more, will comply with the following minimum specific requirement activities of equal employment opportunity:

    The equal employment opportunity requirements of 23 CFR, Part 230, Subpart A.

    Special Provisions of FHWA PR 1273. 

The contractor will include these requirements in every subcontract of $10,000 or more with such modification of language as is necessary to make them binding on the subcontractor.

On-Site Monitoring

Purpose

The purpose of on-site monitoring is to determine the contractor’s compliance with the contract’s affirmative action obligations.  The DEEOCC has the primary responsibility of conducting on-site monitoring of active projects within the districts. 

Safety Rules

The DEEOCC should follow the ODOT safety policy.  Request and review this information prior to going on-site.

How to Conduct On-Site Monitoring

In the case of routine on-site monitoring, it is suggested that your name be added to the construction daily diary.  If there is no trailer on the project site, note the date and time of the on-site review.  In the event that the on-site visit is of a more covert nature, it is at your discretion whether you identify yourself to project personnel prior to conducting employee interviews.  Verify the following at each on-site:

A.      All bulletin board requirements are in place on the project and posted in an area readily accessible to present employees and applicants for employment.  Please note findings on EEO Project On-Site Visit Report;

B.       The EEO policy of the Prime Contractor is posted along with the EEO poster. The text of the EEO policy will be as required in the Special Provisions, or one that includes equivalent wording in addition to describing other general or specific procedures to implement equal opportunity. The DEEOCC must ensure that the company EEO Policy is spread out so all of the pages are visible.  The EEO Policy must be signed by the company’s chief policy-making official and must identify the company’s EEO Officer and his/her phone number;

C.       All employee facilities are desegregated;

D.      Minorities/females are employed and integrated into the various crafts of the project/area workforce;

E.       The contractor's and/or subcontractor's supervisors have been advised of the contractor's EEO commitments (complete Superintendent Interview Form).  Also, determine whether employees have been advised in meetings or by personal notice that EEO requirements will be honored (complete employee interview form);

F.       The contractor has personnel on the project in an apprenticeship or on-the-job training program. If so, those minority/female employees are in the training program;

G.      The contractor, or an authorized representative, periodically conducts inspections and/or reviews to ensure that discriminatory working conditions and/or employment practices do not exist on the project site; and

H.      The contractor's EEO Officer visits the project site and is known to State project personnel.  

Explanation of Interview Forms

EEO Project On-Site Report:

Record all On-Site Observations (bulletin board information; equitable toilet facilities; indication of harassment or intimidation).  Obtain from the prime and subcontractor’s superintendent/foreman the headcount of employees working on the day of the on-site visit.  Document any additional observations/comments.

Superintendent/Supervisor’s Interview Form: 

Complete questions 1-10 when interviewing a superintendent regardless of whether the superintendent works for the Prime or a subcontractor on the project.

Complete questions 11-16 when interviewing the Prime’s superintendent.

Complete questions 17-20 when interviewing the DBE subcontractor’s superintendent.

Interview each superintendent at least once during the construction season. 

DBE Commercially Useful Function Project Site Review Form (CR-6):  This form is to be completed when there is a DBE working onsite or when the DBE delivers materials to the project.  A new form shall be completed for each DBE subcontractor working on or supplying for the project.   Additional forms shall be completed each time a new/different DBE foreman or superintendent joins the project.

Incident Report and Complaint Intake Form (Cr-4 and Cr-5)

If during the on-site, potential EEO violations are observed, i.e., inappropriate graffiti, offensive language, racial slurs, inappropriate jokes, harassment, etc., the DEEOCC will document the observations using form CR-4.  Where necessary, the DEEOCC shall obtain additional information from the contractor or field personnel.  The DEEOCC is responsible for bringing these issues to the attention of the contractor for resolution. The contractor must provide to the DEEOCC copies of all resolutions/outcomes.  The DEEOCC will keep this documentation in a file separate from the project file.

When an allegation of discrimination and/or harassment, i.e., a formal complaint, is brought to the attention of the DEEOCC, the DEEOCC shall complete the Discrimination Intake Form (CR-5) and forward it to Central Office, Office of Contracts.  The DEEOCC shall keep all aforementioned documentation in a file separate from the project file.  Central Office shall be notified of repeated discriminatory issues involving the same contractor. 

ODOT’s On-The-Job Training Program

Objective

Training and upgrading of minorities, females and disadvantaged persons toward journey-person status is the primary objective of the On-the-Job Training Program.

Highlights

The program is not project specific.        Tracking is done on an annual basis.       All contractors (prime and sub) are eligible to participate.       Training is permitted on any contract held by the contractor, whether or not it is Federal funded, provided the contractor holds one (1) Federal funded project during the year.        ODOT does not provide any monetary reimbursement.

Training Requirements

The minimum length and type of training for each classification will be as established in the training/apprenticeship program selected by the contractor.  Each trainee must have a training program approved by ODOT.  Contractors registering their apprentices/trainees in ODOT’s OJT program must be involved in at least one Federal project per calendar year in order to get FHWA training credit.  All ODOT OJT trainees not registered in a union apprenticeship program must be approved by the DEEOCC.

The contractor shall submit to the DEEOCC in the company’s home office district and outline of the type of training to be conducted.  The intent of these provisions is to provide real and meaningful training in the construction crafts.  Off-site training is permissible only when it is an integral part of an approved training program and does not comprise a significant part of the overall training.  Apprentice and On-the-Job Training are permissible in the following crafts:  equipment operator, carpenter, cement masons, iron worker, truck driver, electrician, and laborer.  Training in the laborer classification may be permitted provided that significant and meaningful training is provided and approved by the state agency.  Training is also permissible in lower level management positions such as office engineers, estimators, timekeepers, etc. where the training is oriented toward construction applications.  Training is not permitted in the following classifications:  bookkeeper, clerk/typist, secretary, etc.

A contractor not registered as a training agent with the Ohio State Apprenticeship Council may choose to adopt an existing ODOT training program.  Adoption of an ODOT approved training program will ensure the trainee has successfully completed a sufficient number of hours of training.  The contractor shall estimate, outline and submit to the ODOT DEEOCC the total number of hours that it will take for the trainee to complete the program and ensure that trainee’s skill is comparable to journeyperson level.  The contractor must ensure that the company maintains equipment and fully trained journey level workers at all times to train apprentices or On-the-Job Trainees in the work processes.  A training program approval letter shall be sent to the contractor by the DEEOCC.  The ODOT approval letter shall be valid certification that the contractor is an approved training agent and shall be prima facie proof of compliance with this requirement.  The ratio of apprentices to journey level workers shall be in accordance with the accepted standard for the particular craft or occupation.

Reporting Requirements       

A CR-1 report is to be completed by the Contractor on each trainee registered in ODOT’s OJT Program and submitted to the DEEOCC in which the contractor’s home office is located.

The DEEOCC shall report each apprentice/trainee in the COREP program as soon as the CR-1 report is received by the district.  Work hours should be reported when the trainee ends work for the year, terminates employment, or reaches journey-person status.  Keeping the report current is vital to the Office of Contract’s ability to respond to questions by special interest groups.

CR-1 reports should be submitted by the contractor at the following times:

·         When the trainee begins work with the contractor;

·         When the trainee’s employment is terminate;

·         At the end of the calendar year, with a year to date summary of the work hours performed by the trainee; and

·         When the trainee reaches journey-person status.

The contractor is required to submit to the district a year-end CR-1 report no later than January 5th.  This report shall cover the trainee’s work for the preceding year.  The contractor should submit the reports to the district in which the contractor’s home office is located.  The DEEOCC shall send year-end reminder letters to the contractor in mid-December requesting final hours.

Apprentice Certification

All Contractors shall submit to the district in which the company’s home office is located their own Training Program for approval or the Apprenticeship Certificate from the Ohio State Apprenticeship Council. 

All ODOT OJT Trainees must have the appropriate certification.  It is the responsibility of the Contractor to obtain Apprenticeship Certificates from the Ohio State Apprenticeship Council.  The union apprenticeship agreement is not acceptable verification of an apprentice’s enrollment in a union sponsored training program.  Copies of all Apprenticeship Certificates, regardless of whether they have registered in ODOT’s OJT program, must be submitted to the DEOCC in the company’s home district each time an apprentice is hired by the Contractor. The DEOCC shall advise the Contractor whose apprentices are not registered with ODOT’s OJT Program that they must register those apprentices in the ODOT OJT Program.  The DEOCC shall then compare the information found on the CR-1 report with those OSAC certificates received to ensure that all trainees/apprentices are registered in ODOT’s OJT program.

Subcontractor Notification

Prime contractors are required to notify their subcontractors in writing of their EEO obligations on the project.  A copy of the notification shall be sent to the DEEOCC.

Forms PR-1391 and PR-1392

Requirements

Form PR 1391 is to be completed annually by each contractor and each subcontractor holding contracts or subcontracts exceeding $10,000 except as otherwise provided for under 23 U.S.C. 117. The employment data entered should reflect the work force on board during all or any part of the last payroll period preceding the end of the month of July.

The DEEOCC should send a reminder letter to all contractors with home offices in their district no later than July 15.  The reminder should say that the report is due to the district no later than August 10.   Reports should be gathered by each district for only the contractors with home offices in their district.

The DEEOCC should check each report for accuracy and completeness.  Contact the contractor for corrections and incomplete reports.

When completing the 1392 report, count only the number of contracts and the dollar amounts of the prime contractor.  Counting the subcontractor’s project numbers and dollar amounts would result in inflated figures, as these totals are already covered on the prime report.

Contract Compliance Review Procedures

The reviewing officer will also make a physical tour of the project site and meet with employees in each trade.

Criteria for prioritizing the Contractors to be reviewed

When selecting contractors for review, priority in scheduling reviews shall be based on the following:

·         Contractors whose workforce holds the greatest potential for employment and promotion of females and minorities, particularly in the higher skilled crafts and occupations;

·         Contractors working in areas that have a significant minority and female labor force within the recruitment area;

·         Contractors who have not been reviewed in the last 36 month (36) months;

·         Contractor participation or nonparticipation in ODOT’s On-the-Job Training program;

·         Where compliance with the equal opportunity requirements is questionable;

·         Reviews specifically requested by the FHWA;

·         Contractors who are continually delinquent in sending necessary EEO reports to the DEEOCC or who routinely fail to achieve DBE goals; and

·         Contractors who during the on-site visit the DEEOCC determines has failed to inform their personnel of the company’s affirmative action practices.

When performing the Contract Compliance Review, the DEEOCC shall also consider the geographic area from which the contractor recruits employees, i.e. reasonable recruitment area, an hour’s drive from the project and the county in which the Federal project is located.  When reasonable, reviews shall be conducted prior to or during peak employment periods.

Contractor Notification

The contractor will be notified of the CCR in writing by certified mail with return receipt requested or by e-mail attachment. If the Contractor’s Self Analysis Packet is sent by e-mail attachment, request that the contractor send a “received” e-mail.  If a “received” e-mail is not returned to the DEEOCC within 48 hours the DEEOCC must call the contractor to verify that the Self-Analysis Packet was received, the contractor opened it and is able to read it. 

The suggested notification time line is to send by certified mail to contractor six weeks prior to the review.  The six week breakdown is as follows:

·         5 to 7 days for the contractor to receive the certified notification letter.

·         Two weeks for the completion of the Contractor’s Affirmative Action Evaluation (Contractor’s Self-Analysis Packet) and supporting documentation.

·         5 to 7 days for return mail from contractor.

·         Two weeks for the DEEOCC to analyze the data and prepare for the review. to the on-site meeting

**Notification sent by e-mail may, at the reviewer’s discretion, be sent four weeks prior to the on-site meeting.  This notification shall include the scheduled review date and a list of authorities.

The contractor notification will also include and detail the purpose of the review, required attendees and a list of required documents. 

Superintendent’s Interview Form

Considering the confidential nature of the question on the Superintendent’s Interview Form ODOT requests that the interview form be mailed directly back to the reviewer one week prior to the compliance review on-site.  If mailing the notice, include a self-addressed stamped envelope for the Superintendent’s Interview Form.

NOTE:    A Contractor’s Self-Analysis Packet shall be sent with the notification letter.

The contractor will be requested to provide a meeting place on the day of the visit.  Reviews should be held at the jobsite only if the contractor office is located out of the state of Ohio.  Generally, the contractor does not keep the required documents necessary to complete an EEO contract compliance review at the project site.

The DEEOCC will notify all joint venture participants that the analysis set is to be completed as one (1) contractor, not separately.

The contractor will be requested to supply all of the following information to the DEEOCC prior to the review.  The Contractor’s Self-Analysis Packet, all back up documentation and the signed and notarized affidavit shall be kept intact.  These originals become a legal document and may not be altered in any manner.   It is mandatory that this information be copied and the copies placed in a review notebook prior to the on-site visit.  It is suggested that the original Contractor’s Self-Analysis Packet be stored in a separate area from the review notebook.  Please see section “Instructions for Creating Contract Compliance Review Notebook”.

The Contractor’s Self-Analysis Packet.

The contractor’s self-analysis packet shall include the following:

·         Contractor’s EEO policy and Contractor’s Sexual Harassment Policy; 

·         A BLANK copy of the company’s purchase order and subcontract agreement.  For subcontractors this should be the documents used by the Contractor and not by the prime;

·         Documentation of the solicitations to all DBE contractors contacted as potential subcontractors, vendors, or suppliers for the project(s) being reviewed;

·         Contractor’s employment application, if one is utilized;

·         A statement of the status of any action pertaining to employment practices taken by the Equal Employment Opportunity Commission (EEOC), Ohio Civil Right Commission (OCRC), or other Federal, State, or local agency, against the contractor or any of their employees;

·         A list of promotions made during the past six months, which includes name, race, national origin, sex, previous job held, job promoted into, and corresponding wage rate; and

·         A list of construction employees (master payroll) who worked for the company during the review period (including project supervisory personnel).  Include the name, date of hire, job classification, wage, race, national origin, and sex.          

Current Form PR 1391

Names and titles of personnel that will be representing the contractor's firm at the on-site review 

Transfer this information to Page 1 of the final determination packet, hereafter known as the Affirmative Action Evaluation (AAEVAL).

Documentation showing current EEO Officer’s job duties and responsibilities 

This should include all duties not just those pertaining to EEO/AA.   What experience does the EEO Officer have which would qualify as EEO related?  If no previous experience is identified, what training has been provided?  What has the EEO Officer done to increase his/her knowledge of the program?  What authority does the EEO Officer have to accomplish program objectives?  Ascertain if the EEO Officer has been given the authority to implement program objectives formally or informally. 

Obtain the following information:

·         List of all members of the contractor’s staff who are authorized to hire, supervise, promote, and discharge employees or make recommendation for such actions; and 

·         Documentation of indoctrination of this staff regarding company EEO obligations;

·         A list of company personnel responsible for recruitment; and 

·         Documentation showing training of recruitment personnel on company EEO hiring procedures.

If required, review union agreement for exclusive referral clause and EEO provisions.  In the event the contractor has a valid bargaining agreement providing for exclusive hiring hall referrals, he is expected to observe the provisions of that agreement to the extent that the system permits the contractor’s compliance with equal employment opportunity contract provisions. 

If for any reason the contractor is being uncooperative and will not respond to deadlines, letters, phone calls, etc. from the district, the contractor will be found in noncompliance and the Central Office Deputy Director of the Division of Construction Management will be notified.  The Deputy Director of the Division of Construction Management will issue a show cause notice scheduling the contractor’s show cause meeting.  The meeting will be scheduled within 30 days of the date of the show cause letter.

Criteria for Determining Type of Review

The following criteria shall be used to determine whether a contract compliance review is conducted on-site in person by the DEEOCC or via a desk audit:

On-Site Criteria

Desk Audit Criteria

Contractor has never been reviewed.

Follow-up review.

Contractor was in “non-compliance” during last review.

Contractors repeatedly found “in-compliance.”

If preliminary review of the Contractor’s Self-Analysis Packet and supporting documentation indicate the contractor should be found in “non-compliance” the review defaults to an automatic on-site.

Contractors with only paper deficiencies (deficiencies that can be corrected within 10 days of the review or less).

If Contractor fails to submit the Self-Analysis Packet and/or supporting documentation for the desk audit, the review defaults to an automatic on-site.

A contractor submitting a complete packet with all supporting documentation which indicates good faith effort has been made in all categories.

If the Self-Analysis Packet received from the Contractor or the desk audit demonstrates minimal good faith effort, the review defaults to an automatic on-site, e.g., no recruitment documentation, no utilization of minorities and females when there were known hiring opportunities and insufficient documentation was provided to justify the non-hiring of minorities and females.

If the Contractor’s Self-Analysis Packet and/or the supporting documentation are grossly incomplete, the review defaults to an automatic on-site.

Contractors found in “non-compliance” by other agencies.

Contractors with formal charges of discrimination pending.

When the DEEOCC has been notified of possible discrimination (harassment, intimidation, possible coercion on the job site).

Preliminary Analysis (Phase I)            

The reviewing officer shall consider the following information:

·         Does the contractor have an EEO policy and how it is disseminated?

·         Who is responsible for the company’s EEO functions and are they effective in his/her role?

·         How does the contractor recruit minority and female employees?

·         How does the contractor ensure that the company does not discriminate?

·         On what basis does the contractor train and promote employees?

·         How does the contractor monitor subcontractors to ensure the EEO and affirmative action programs are implemented?

·         To what extent does the contractor use Disadvantaged Business Enterprises?  Are DBE subcontractors utilized on non-goal projects?              

·         What types of records and reports are maintained by the contractor to monitor affirmative action progress?

·         What type of documentation is maintained by the contractor to show Good Faith Efforts were made to secure minority and female employees?

Before the onsite verification and interview, the reviewer shall analyze the employment patterns, policies, practices, and programs of the contractor to determine whether or not problems exist by reviewing information relative to:

·         The contractor’s current workforce; 

·         The contractor’s relationship with referral sources, e.g., unions, employment agencies, community action agencies, minority and female organizations, etc.;

·         Verify that recruiting phone calls, faxes or letters to unions, job service, vocational schools and other sources were actually made by calling the source named in good faith effort documentation. If sources have no knowledge of contractor's efforts, note this to be discussed at the on-site conference;             

·         The minority and female representation of recruitment sources;

·         The availability of minorities and females with requisite skills in a reasonable recruitment area;

·         The status of complaints or action pertaining to employment practices taken by the Equal Employment Opportunity commission (EEOCC), Ohio Civil Rights Commission (OCRC) or other Federal, State or Local agency, against the company or any of its employees;

·         The company’s I-29 reports covering the review period.  View on the web at http://eodreporting.oit.ohio.gov/searchEODReporting.aspx;

·         Participation of the contractor in OJT programs;

·         Previous compliance reviews.  A review of previous review reports can assist the reviewing officer in identifying problem areas uncovered in the past and following up on these areas;

·         On-site interviews; and

·         Verification of Commercially Useful Function (CUF).

By examining this information, it can be determined whether potential problem areas exist in the contractor’s employment patterns, policies, practices, and programs.

Preliminary Analysis (Phase II)

The following sections are to be used as a reference tool when reviewing the Contractor’s Self-Analysis Packet.  Ask yourself the questions listed in each category.  If you do not have a clear understanding of each section of the contractor’s Self-Analysis Packet, discuss those sections during the review with the contractor keeping those questions in mind.  These questions should not be specifically asked during the review.  Instead, discuss in detail the pertinent section of the Contractor’s Self-Analysis Packet until you can answer the questions listed below.

Contractor/Project Information

Principal Policy and EEO Officer:  The people listed should be in attendance during the On-Site visit portion of the compliance review.  The Principal Policy Officer may attend just the beginning and ending portions of the review if the EEO Officer has the authority to administer the contractor’s EEO/Affirmative Action Program with the authority to hire, discipline, layoff and terminate employees.         

Review the dollar amount for size and whether the contractor/subcontractor may have opportunity to hire for their portion of the contract. 

Check whether the review is being conducted prior to or after the contractor/subcontractor’s peak employment period.  Where possible, it is advisable to conduct the review prior to peak employment period, in case corrective action in hiring is noted during the review.

Check the percentage of project complete.  When reviewing a subcontractor, this figure should represent the portion of the subcontractor’s work only.

Note who is listed as the Superintendent for the project.  Is this the person you have seen and interviewed on the project?

Contractor Project List

Review the list of projects to determine how much work the contractor/subcontractor has in the Economic Area/County under review.  If the majority of the contractor’s work is in a different Economic Area/County than the one under review, note this in the summary narrative of the review.             

Union and Recruitment Data

Review the list of unions with which the contractor has a collective bargaining agreement. The reviewer should become familiar with the collective bargaining agreements of each union.  Do any of the unions listed have exclusive referral?   

Contractor’s Outside Recruitment Sources

Review the list of outside recruitment sources to determine if the contractor utilizes recruitment sources other than the unions. 

Recruitment

Review the recruitment sources supplied by the contractor.  Does the contractor recruit solely from the union?  Note in the review summary if the contractor has not recruited outside the union.  Does the contractor list outside recruitment sources, but has not contacted any?  Did the contractor supply documentation of recruitment and support efforts, including two way communications?  How has the contractor conducted systematic and direct recruitment or support to either the Union or other entities (indirect recruitment)?  Please note: Support of local and national community action and community service programs designed to improve the employment opportunities of minorities and females can also serve to assist the Union(s) that have signatory agreements with the Contractor. 

Does the contractor have a plan of action to recruit minorities and females, if his/her regular recruitment source(s) fails to provide minorities and females for his/her workforce?  Obtain documentation from the contractor of all recruitment efforts made, both to and from those sources. 

Support of community groups is an example of indirect recruitment.  Community-funded groups which are concerned with equal employment opportunity and affirmative action are also important sources for recruitment for contractors.  These sources must be contacted and documentation must reflect such contact.  Examples of community funded groups are the Urban League; National Association for the Advancement of Colored People (NAACP); League of United Latin American Citizens (LULAC); and the National Organizations of Women (NOW).

Does the contractor have an adequate applicant pool of minorities and females to select from? 

If a contractor is signatory to a Union it does not eliminate the contractor’s obligation to make good faith efforts to hire minorities and females or support those local community resources which can assist the Contractor in resolving employment problems.

Did the contractor state that they recruit solely from the union?  Did the contractor state that the union could not fill requests for minorities and females? 

Please note the following: 

23CFR, Part 230, Subpart A, Appendix A, (8)(d).

“In the event the Union is unable to provide the contractor with a reasonable flow of minority and females referrals within the time limit set forth in the collective bargaining agreement, the contractor will, through independent recruitment efforts, fill the employment vacancies without regard to race, color, religion, sex, or national origin; making full efforts to obtain qualified and/or qualifiable minority group persons and females.  The U.S. DOL has held that it shall be no excuse that the union with which the contractor has a collective bargaining agreement providing for exclusive referral failed to refer minority employees.  In the event the union referral practice prevents the contractor from meeting the obligations pursuant to Executive Order 11246, as amended and these special provisions such contractor shall immediately notify the State Highway Agency.” 

Although the Contractor may not hire “off the street”, it must provide evidence of its efforts to assist the Unions’ own Affirmative Action obligations. 

Note whether the contractor has notified outside recruitment sources, vocational schools and community organizations of apprenticeship or other training opportunities for minorities and females. The contractor must offer this notification not later than one month before the date of acceptance of applicants for these programs. 

Additionally, the Contractor should provide evidence of its support of local and national community action and community service programs designed to improve the employment opportunities of minorities and females.  Documentation of the Contractor’s support of community action and service programs may include copies of checks, advertisements in brochures, or letters confirming the donation of equipment, the participation of company employees, etc.

Where the Contractor can provide little or no evidence of support of such programs, the DEOCCC should identify suitable programs and appropriate means of support as corrective actions. Evaluation of compliance with this requirement, and a decision to cite the contractor, requires professional judgment by the DEOCCC. Assessing the contractor's compliance in this area is similar to assessing compliance with the requirement to develop and execute action-oriented programs.

Consideration of females and minorities not currently in the workforce; 41 CFR 60-2.13(j): The Contractor must give consideration to minorities and females not currently in the workforce having requisite skills who can be recruited through affirmative action measures. This means that, among other things, the Contractor should utilize, as recruitment sources, agencies such as those which offer pre-apprenticeship training or direct employment placement to veterans, displaced homemakers, individuals in rehabilitation programs, and other individuals who, for one reason or another, have been out of the workforce. The DEOCC should ask for documentation that the contractor supports, participates in or requests employment referrals from such agencies. In addition, the Contractor may also have taken action, such as establishing part-time, job-sharing, or flex-time programs, establishing onsite day care programs, etc., to attract and retain in employment skilled individuals who would otherwise be excluded from gainful employment. Note whether the contractor encourages internal recruitment of minorities and females.    

Hiring

Efforts to hire and promote females and minorities into “non-skilled”  positions such as superintendents, foremen and other core employees (administrative personnel, engineers, inspectors, quality assurance personnel) are to be evidenced by all contractors.  The Contractor’s Good Faith Efforts for Internal Placements may include the contractor's efforts to:

·         Disseminate information about internal opportunities (Are job openings posted? If so where, when, how long, and for which jobs or classes of jobs?);

·         Provide training opportunities (including apprenticeship programs, on-the-job training, and tuition reimbursement);

·         Provide counseling and encouragement to minority/female employees to apply for internal openings;

·         Recruit externally into feeder job groups; and/or

·         Review selection criteria and selection procedures with responsible officials and managers to ensure that they are familiar with the Contractor's EEO policies, that the selection criteria are applied in a nondiscriminatory manner, and that the selection criteria do not have a discriminatory impact.

Training

Training programs and requirements may be overlooked by reviewing officers as tools to address areas of minority/female underutilization.  List all OJT and/or apprenticeship programs the contractor is participating in and how effective the programs have been in training minorities and females.  Obtain list of trainees enrolled by the contractor on the project being reviewed.  How has the contractor advised employees and applicants for employment of available training programs and entrance requirements for each? Who is responsible for this?  How has the contractor utilized training programs to increase minority/female representation in trades where they are being underutilized? Go back to those trades identified earlier in the review where underutilization exists.  Are trainees being trained in trades for which there is a shortage of qualified personnel?  The intent here is to ensure the most effective use of training programs. How has the contractor periodically reviewed the training and promotion potential of minority/female employees? Are employees interviewed? By whom? How often?  Is particular attention paid to minorities/females in the lower skilled classifications?  List specific examples of instances where contractor has encouraged employees to apply for training and promotion.  What procedures are in effect to ensure that each trainee is provided with a copy of the training program that the trainee is to follow (applicable to nonunion contractors)?

On-the-Job Trainees (OJT)

Are the OJTs listed registered with the Ohio State Apprenticeship Council?  If the contractor is nonunion, has the training program been submitted and approved by the contractor’s home ODOT District?  Does the training plan mirror the field work outline of a similar craft union’s apprenticeship program?  Has the home ODOT district EEO Coordinator received CR-1's on all trainees listed?  Where applicable, have OSAC certificates been received by the ODOT district overseeing the project under review?   Does the list of On-the-Job Trainees include minorities and females?  This information will indicate whether the contractor is taking a proactive approach to exposing youth to the construction trades.   This type of exposure can include working in the construction yard, shop or office.

Reminder - utilization is based on hours worked,

not the number of employees hired.

Project and Statewide New Hires and Hours

Review the list of new hires to see when the minority and female employees were hired.  Were they part of the contractor’s workforce prior to work commencing on the project under review or were the minorities and females hired specifically for that project?  Compare the new hire dates of the minorities and females with the non-minority males.  Were the females and minorities hired after most positions were filled?  When conducting your on-site project visits, did you interview any of the minorities or females shown on the new hire list?  If not, ask the contractor where the minorities and females were working.  Check the master payroll for layoff dates.  Were the minorities and females laid off first?  Look for discriminatory patterns.

When reviewing all of the contractor’s hours worked (both public & private), make note whether the hours of work for minority and female employees was reasonable.  If percentages are low, ask the contractor why they are low and what good faith efforts were made to increase the hours.

If deficiencies are within the skilled crafts when comparing to the census data check the New Hire list for opportunities for hire.  If the New Hire listing indicates “new hires” placed in the deficient craft, review the breakdown of new hires.

Were minorities and/or females included in the new hires?  If opportunities for new hires existed and no minorities and/or females were hired, the contractor should be found deficient in this craft and this deficiency should be identified in the AAEVAL under recommendations.

If no opportunity for new hires existed, the contractor should not be found deficient in this craft.

Although both female and minority utilization is to be discussed with the contractor during the review, cite the contractor’s deficiencies for final determination as follows:

·         Cite deficiencies noted in the census area only. 

·         Cite female deficiencies noted in the statewide utilization figures only. 

Census Data Website Links 

The census data for the county in which the project is located (identified in the proposal), shall be used as a guide in determining optimal minority and female utilization.

Minority and female utilization obligations by craft per county (applicable to project): 

http://www.dot.state.oh.us/Divisions/ContractAdmin/Contracts/Construction/CountyAvailability-ByTrade.pdf

Statewide utilization obligations by craft (applicable to the Contractor’s statewide workforce): 

http://www.dot.state.oh.us/Divisions/ContractAdmin/Contracts/Construction/StatewideAverages-ByTrade.pdf

Using the census data, locate the contract requirements for minority and female utilization per craft for the county in which the project is located.  Compare the project specific female & minority utilization percentages with the county census data.

Compare the contractor’s statewide female & minority utilization percentages with the statewide utilization as shown on the website: 

http://www.dot.state.oh.us/Divisions/ContractAdmin/Contracts/Construction/StatewideAverages-ByTrade.pdf

If the contractor’s minority and female utilization percentages are less than indicated in the census data, compare those utilization percentages with the contractor’s opportunities to hire.  Use this information to assist in determining if the contractor has made a good faith effort to hire minorities and females. 

NOTE:  Compliance with the goals will be measured against the total work hours performed per craft not the number of employees hired.       

Cite the contractor’s deficiencies for final determination as follows:

·         Minorities on the project, per craft;

·         Females on the project, per craft;

·         Minorities utilized statewide, per craft; and

·         Females utilized statewide, per craft.

EEO Analysis Questionnaire

FHWA Federal Circular PR 1273 states that EEO orientation sessions should be held not less than every 6 months.  Project site EEO meetings should be conducted on a regular basis.  Documentation of the meetings should include the date of meeting, the subject discussed and signature of those in attendance.

Company Personnel Operations

The contractor should have supplied to the reviewer copies of documentation supporting the Company’s personnel actions detailed the Self-Analysis Packet.

If any of the supporting documentation provided to you by the contractor has not changed since the last review, resubmission will not be required.          

Promotions

If the contractor answers “no” to any of the questions, ask the following: 

·         How do minority and female employees get promoted?

·         How do company employees become foremen/superintendents?

As outlined in PR 1273 the company shall hold EEO meetings with all employees having responsibility for hiring, assignment, layoff, termination or other employment decisions not less than once every six months.

All meetings shall be documented with time, place, attendees, subject matter and disposition of subject matter.

As required by Contract Provisions, Federal-aid construction contracts, Federal Circular PR 1273, Part 3B.  “All new supervisory or personnel office employees will be given a thorough indoctrination by the EEO Officer, covering all major aspects of the contractor's EEO obligations within thirty days following their reporting for duty with the contractor.”

Ensure that the company’s EEO Policy is not a policy only on paper, but is actively adopted and implemented by all supervisory personnel. Supervisory personnel can be held liable for violations of this policy and the excuse of “not knowing” will not excuse them from this liability.

The Reviewer shall request a copy of the new hire packet to ensure that it contains all required documents.  

The selection of employees to receive advanced skill level training shall be based on the following factors:

·         The relevancy of the training to current and projected assignments in terms of organizational requirements;

·         The relevancy of the training to identified individual developmental needs;

·         Evidence of the candidate's ability and desire to undertake and complete successfully a comprehensive advanced skill level training program;

·         Evidence of the candidate’s ability to undertake and complete successfully advanced skill training on his or her own time;

·         Training shall be made available to all eligible employees

The process used when considering workforce promotions shall be free of discrimination and shall be based on merit and job related criteria.

The process used when evaluating the workforce for layoffs shall be free of discrimination and shall be based on job related criteria.

Termination policies shall be disseminated to all employees at time of hire.  The contractor’s reasons for terminating an employee shall be documented. 

EEO Policy/Sexual Harassment Statements and Dissemination

The compliance officer should review the contractor’s EEO policy to ascertain whether it is equal to or greater than the policy required by contract provisions, PR 1273. Each policy must include the name and contact information for the company’s EEO Officer.  Additionally, each policy must be signed by the company’s chief executive officer. 

How does the contractor disseminate his EEO policy to all of his employees, i.e., meetings, employee handbooks, paychecks, bulletin boards etc.?  Determine how effective these procedures are.  Employee interviews may be used to follow-up on the effectiveness of procedures.  Are the policies discussed with field personnel?  Does the person responsible for discussing these policies with field employees have a thorough knowledge of the policies?           

Determine how and when new supervisory or personnel office employees are indoctrinated on all major aspects of the contractor's EEO obligations (must be done within thirty days following their reporting for duty).   

Are EEO/AA meetings held not less than once every six months?  

Deficiencies shall be noted in the AAEVAL and discussed with the contractor at the EEO Contract Compliance Review. 

Construction Employment Data

Did the contractor’s project workforce include minorities and females in each craft?  If not, were there new hires for this project in the underutilized craft?  Were the new hires minorities or females?  Did the contractor demonstrate good faith efforts to hire minorities and females in the underutilized crafts?

Did the contractor’s OHIO workforce include minorities and females in each craft?  If not, were there new hires in the underutilized craft?  Were the new hires minorities or females?  Did the contractor demonstrate good faith efforts to hire minorities and females in the underutilized crafts?

Subcontracts, Purchase Orders, Lease Agreements

What efforts has the contractor exerted to solicit bids from and to utilize minority and female subcontractors?  What were the results?  What efforts has the contractor made to solicit bids from or to negotiate with such firms?   NOTE:  Failure of the contractor to solicit quotes from DBE owned firms when there is no DBE goal on the project may be construed as discrimination.   If this situation is noted, please request an explanation from the contractor.

The contractor must have a procedure in place for ensuring subcontractor compliance with the EEO provisions of the contract.  The contractor should also have a plan of action to be taken when a subcontractor consistently fails to comply with the EEO contract provisions.

Sample acceptable procedures for ensuring subcontractor compliance, may include, but are not limited to:

·         Daily project site monitoring by the contractor under review of sub/sub-subs project personnel for representation of minorities and females.

·         Monthly review by the contractor under review of the sub/sub-sub’s project specific monthly utilization report (Input 29 report).

·         Review of certified payrolls submitted by sub/sub-sub.

Sample acceptable actions taken when it is noted that a subcontractor consistently fails to comply with the EEO obligations of the contract.  These may include, but are not limited to:

·         Reviewed contractor shall address the situation with the subcontractor’s superintendent.  Document action taken.  Reviewed contractor shall report all actions taken to their company EEO Officer.

·         If deficiencies are noted during the review of the Input 29 reports or the certified payrolls, the reviewed contractor shall notify the non-compliant contractor’s EEO Officer.

·         Additionally, the reviewed contractor should notify the ODOT DEEOCC regarding the non-compliant subcontractor when corrective action is not taken.

DBE Subcontractor/Supplier Verification

Review the information regarding the DBE requirement of the contract.  Has the contractor fulfilled the contract provisions?  If not, has there been a problem with obtaining DBE’s?  Is DBE work pending on the contract or was it completed by a non DBE contractor?  When will the DBE portion of the contract be completed?  Who are the DBE’s scheduled to complete the contract requirements?  If the requirement has not been fulfilled, verify the information given by the contractor with the ODOT Project Engineer in charge of the project under review.  Note findings in the narrative summary of the review packet.

Nonsegregated Facilities

Applies to contractors, subcontractors, and material suppliers on all Federal-aid contracts and related subcontracts of $10,000 or more.  The intent of this provision, also derived from Title VI, is to ensure that past discriminatory practices of providing separate facilities or prohibiting minority’s access to facilities are eliminated.  By entering into the contract, the organizations and firms certify that they maintain nonsegregated facilities that conform to requirements of 41 CFR 60.1.8. The prime contractor is required to obtain a similar certification from each subcontractor and supplier, as applicable.  One exception to the nonsegregated facilities provision is for the disabled when the demands for accessibility override (e.g., disabled parking). In addition, single-user or separate bathrooms or dressing facilities are also allowable for privacy purposes.

Safety

It is a condition of this contract, and shall be made a condition of each subcontract, which the contractor enters into pursuant to this contract, that the contractor and any subcontractor shall not permit any employee, in performance of the contract, to work in surroundings or under conditions which are unsanitary, hazardous or dangerous to his/her health or safety, as determined under construction safety and health standards (29 CFR 1926) promulgated by the Secretary of Labor, in accordance with Section 107 of the Contract Work Hours and Safety Standards Act (40 U.S.C. 333).

When reviewing the contractors Safety program pay particular attention to the following:

Does the contractor have an active safety and health program in place that deals with general safety and health program elements, as well as management of hazards specific to a construction work site?  Is one person clearly responsible for the overall activities of the safety and health program?  Is there a safety committee or group made up of management and labor representatives that meet regularly and report in writing on activities?  Is there a working procedure for handling in-house employee complaints regarding safety and health?  Are employees advised of the successful efforts and accomplishments that the company is making to ensure a safe, healthy workplace?  Are employee incentives considered for employees or work groups who have excelled in reducing workplace injuries and illnesses?

If the contractor's safety policy does not clearly identify the above listed items, the reviewer shall recommend that consideration be given to improving and developing that particular area and updating the safety manual.

Contractor’s Affidavit

The Contractor’s Affidavit MUST be completely filled out, signed and notarized.

Explanation of the Contractor’s Supporting Information

In addition to the Contractor’s Self-Analysis Packet, the contractor’s EEO Contract Compliance Review Notification Letter requests the following items be sent to the reviewer (supporting documentation that has not changed since the last compliance review will not need to be re-submitted).

EEO Policy/Sexual Harassment Statements and Dissemination

The DEEOCC must ensure that the EEO policy meets the minimum requirements outlined in FHWA 1273.  The EEO policy should include the company EEO Officer’s name and contact information.

The Sexual Harassment policy shall include the definition of sexual harassment, and the repercussions of violating the policy.  The policy must state that violations will result in penalties up to and including termination. 

Both polices must be signed by the company’s Chief Executive Officer.  Policies shall be disseminated to and reviewed with all new hires and current employees not less than once every six months.  Additionally, the policies shall be posted on company home office and on-site bulletin boards.

Subcontract, Purchase Order & Lease Agreement

Any recipient of Federal or State funds must inform all lower tier (subs, sub -subcontractors, material suppliers, lessors of equipment) of the  EEO requirements of the contract by written notification (see subcontractor notification letter requirement in Preconstruction Conference section) and inclusion of the Federal Circular PR 1273 in all transaction documents, i.e.,  purchase orders, subcontracts and lease agreements.

 Equal Opportunity Employer Tagline

“Equal Opportunity Employer” is the tagline that appears on all official company documents (letterhead, purchase orders, etc.).  “EOE” may be substituted for “Equal Opportunity Employer” in company advertising.  The DEEOCC must verify that this tagline appears.

Disadvantaged Business Enterprise (DBE) Subcontractors & Material Suppliers

The contractor shall provide to the reviewer documentation of Disadvantaged Business Enterprises contacted as potential subcontractors, vendors or suppliers for the project being reviewed. Were DBE’s used above and beyond the goal of the project?  Did the contractor use DBEs when there was no contract requirement?   If the contractor utilized DBE’s above and beyond the requirement or when there was no DBE contractual requirement, note the contractor’s good faith efforts in the appropriate area of the Final Determination Packet and in the summary under Observations.

Subcontract agreements between the contractor and the applicable DBE on project(s) being reviewed.

The purpose is to verify the participation as required by the Contract Bid Proposal and C-92's.

Promotions

A list of promotions made during the review period, including race, national origin, and sex, of the employee, previous job held, job promoted into and corresponding wage rate.  Were all those promoted white males?  If so, ask the contractor why minorities and females were not considered for promotion. Determine from the contractor’s answer whether there appears to be any discrimination.

Master Payroll

A list of construction employees who worked for the company during the review period (include project supervisory personnel).  When were minorities and females hired and laid off?  Are these dates consistent with hire and layoff dates of white males in the same classifications?  Determine whether there appears to be any discriminatory pattern.

I-29 Reports

Submitting the I-29 reports is no longer a requirement of the Contract Compliance Review process as the Form I-29 may be viewed on line at http://eodreporting.oit.ohio.gov/searchEODReporting.aspx   However, information in the reports is important and shall be reviewed prior to the onsite visit.  Do the reports indicate that minorities and females were utilized throughout the year as equally as white males?  The appearance of a discriminatory pattern may not indicate discrimination.  Does the contractor’s workforce include apprentices?  Have the apprentices been registered in ODOT’s On-the-Job Training Program?  Is the ratio of apprentice to journeyperson within the prevailing wage ratio for each craft?  All issues shall be discussed with the contractor during the on-site visit and the results of the discussion documented in the appropriate area of the Final Determination Packet and in the summary under Observations. 

Names and Titles of Personnel Who Will Be Representing the Contractor’s Firm at the On-Site Review

EEO Officer’s Duties and Responsibilities:

·         The contractor will designate and make known to the SHA contracting officers an EEO Officer who will have the responsibility for and must be capable of effectively administering and promoting an active contractor program of EEO and who must be assigned adequate authority and responsibility to do so.

·         Indoctrination of staff that are authorized to hire, supervise, promote, and discharge employees or make recommendations for such actions.

·         The contractor shall provide documentation of the indoctrination of staff regarding the company’s EEO obligations.

List of Company Personnel Responsible for Recruitment

The contractor shall provide documentation showing training of recruitment personnel on the Company’s EEO hiring procedures.

Documentation showing training of recruitment personnel on company EEO hiring procedures;.

Contract bid proposal(s) for the projects being reviewed.

Information pertinent to the review is obtained from reviewing the contract proposal, i.e., DBE goal, wage rates, utilization information, safety.

Leasing/Rental Agreements

Review lease/rental agreements the contractor has for equipment leased/rented. The purpose is to verify: that equipment and/or operator on site is not regularly used by or do not regularly work for the prime contractor or another subcontractor on the project; verify that equipment leased by a DBE subcontractor is not owned by the prime on the project.  Ensure that the EOE tag line appears on all lease/rental agreements.

Conducting a Formal EEO Contract Compliance Review

Review of the entire Contractor’s Self-Analysis Packet occurs at this meeting.

Discuss any items which need further clarification.

Obtain all back up documentation not previously provided.

During the Exit Conference discuss all contractor deficiencies.

Onsite Verification and Interviews

Phase III of the review consists of the construction or home office site visit(s).  During the initial meeting with the contractor, the following topics shall be discussed:

Objectives of the Visit

The material submitted by the contractor, including the actual implementation of other employee referral source system and any discrepancies found in the material.

Physical Inspection

The DEEOCC will make a physical tour of the office, shop, and project site to determine that:

·         EEO posters, EEO policy, and the name and phone number of the company EEO Officer are displayed in conspicuous places (bulletin board information) in the office shop or other in-house locations.

·         Facilities are provided on a non-segregated basis (e.g. work areas, washrooms, time clocks, locker rooms, storage areas, parking lots and drinking fountains).

·         Reported employment data is accurate.

·         Meetings have been held with employees to discuss EEO Policy, particularly to new employees.

·         Employees are aware of their right to file complaints of discrimination.

·         Project on-site visits may be conducted prior to review.

Exit Conference

During the exit conference with the contractor, all preliminary findings shall be discussed.

Minor deficiencies shall be corrected and submitted to the reviewer within 10 days of the Exit Conference.                        

Compliance Determinations

The evidence obtained at the compliance review shall constitute a sufficient basis for an objective determination by the DEEOCC conducting the review of the contractor’s compliance or noncompliance with contractual provisions pursuant to 23 USC; 23 CFR Pts. 200, 230, 633; 29 CFR; Civil Rights Act of 1964, as amended; Special Provisions of FHWA 1273; Title VI; and FHWA EEO Special Provisions implementing the Federal-Aid Highway Act of 1968, where applicable.

A contractor shall be considered to be in-compliance when the equal opportunity requirements have been effectively implemented or there is evidence that every good faith effort has been made toward achieving this end.  Efforts to achieve this goal shall be result-oriented, initiated and maintained in good faith, and emphasized as any other vital management function.

Examples of effective implementation of EEO requirements are:                           

·         The contractor’s equal employment opportunity (EEO) policy meets the minimum guidelines as outlined in FHWA PR 1273.

·         Dissemination of the policy and education of supervisory employees concerning their responsibilities in implementing the EEO         policy.

·         The EEO officer has the authority and responsibility to effectively administer the EEO requirements.

·         Evidence of the contractor’s recruitment activities, especially those activities which establish minority and female recruitment and referral procedures.

·         Participation in ODOT’s on-the-job training program, especially when minorities and females are utilized.

·         The contractor’s review of all personnel actions to ensure equal opportunities.

·         The contractor’s efforts to recruit minorities and females from the unions with which the contractor holds collective bargaining agreements.

·         Contractor’s efforts and implementation to provide non-segregated facilities, as required by contract provisions.

·         The contractor’s procedures for monitoring subcontractors and their utilization of minority and female subcontractors and/or subcontractors with substantial minority and female employment.

·         The adequacy of the contractor’s records and reports.           

A contractor shall be considered to be in-compliance when the equal opportunity requirements have been effectively implemented or there is evidence that every good faith effort has been made toward achieving this end.  Efforts to achieve this goal shall be result-oriented, initiated and maintained in good faith, and emphasized as any other vital management function.

If a contractor is determined to be in-compliance, the DEEOCC shall, within 15 days, prepare and submit to Central Office Deputy Director of the Division of Construction Management, the AAEVAL.  Preparation of the review packet includes:        

·         Completion of the AAEVAL

·         Submitting the AAEVAL to the District Construction Administrator (DCA) for concurrence and signature

·         Sending signed copy of AAEVAL to Central Office Deputy Director of the Division of Construction Management for final concurrence

A contractor shall be considered to be in noncompliance when:            

·         The contractor has discriminated against applicants or employees with respect to the conditions or privileges of employment

·         The contractor fails to provide evidence of every good faith effort to provide equal opportunity

·         The contractor fails to meet Voluntary Corrective Action Plan (VCAP) requirements

Once the onsite verification and exit conference have been completed and a compliance determination made, the contractor shall be notified of the compliance determination in writing by the ODOT Office of Contracts.  This written notification shall be sent to the contractor within 30 days following the receipt of the completed review packet from the DEEOCC.                                        

Show Cause Notification

If a contractor is found to be in noncompliance, action efforts to bring the contractor into compliance shall be initiated through the issuance of a show cause notice sent by the Deputy Director of the Division of Construction Management.  The notice shall advise the contractor to show cause within 30 days why sanctions should not be imposed.

A Show Cause Notice shall be issued when a determination of noncompliance is made based upon:

·         The findings of a compliance review, or

·         The results of an investigation which verifies the existence of discrimination, or

·         If the contractor failed to meet conditions of CAP.

The scheduled location, date and time of the Show Cause Meeting shall be furnished to Central Office Deputy Director of the Division of Construction Management by the DEEOCC.   Central Office may attend the Show Cause Meeting.  Likewise, the District may request Central Office presence.

Show Cause Procedures

During this 30-day period stated in the Show Cause Notice, the DEEOCC will be required to attempt conciliation with the contractor. These conciliation and negotiation efforts shall be directed toward correcting the contractor’s deficiencies and initiating a Corrective Action Plan (CAP).

A CAP addresses the deficiencies identified in the Show Cause Notice. The plan must specify what action is going to be taken and when that action can reasonably be expected to be completed. If there is insufficient time remaining to correct the deficiencies on the project(s) found in noncompliance, it should be addressed in the CAP that the contractor is required to meet the conditions of the CAP until a follow-up review can take place on a future project(s). Each item in the plan should correct the deficiencies stated in the Show Cause Notice.

Show Cause Meeting

The contractor’s final CAP will be submitted to the DEEOCC and discussed at the Show Cause Meeting.   Additionally, the contractor will be required to submit monthly reports as part of the process to correct the deficiencies stated in the Show Cause Notice (SCN).

Once the CAP is accepted by Central Office and the DEEOCC, it becomes the contractor’s CAP and the contractor will be notified that the plan is accepted and should be implemented.

If the contractor fails to develop, sign and implement a CAP within the 30-day period stated in the SCN, the Department shall impose such sanctions as it or the Federal Highway Administration may determine to be appropriate, including but not limited to:

·         Letter of reprimand.

·         Withholding of payments to the contractor under the contract until the contractor complies.

·         Cross-withholding from future projects.

·         Contract termination, cancellation (in whole or in part) and/or other remedies available by law including suspension, revocation, and/or debarment.

Factors to be considered in issuing sanctions include, but are not limited to:

·         The magnitude and the type of offense.

·         The degree of the contractor’s culpability.

·         Any steps taken to rectify the situation.

·         The contractor’s record of performance on other projects.

·         Whether the contractor falsified, misrepresented, or withheld information.

If the contractor implements a CAP, it will be considered that the contractor is in-compliance providing the monthly reports and other documentation required by the CAP indicate that real progress is being made toward eliminating the deficiencies identified in the SCN or that a good-faith effort is being made CAPs can be amended if the contractor has carried out each committed action and those actions are not producing the intended results. Following the Show Cause Meeting, a copy of the accepted CAP along with an IOC outlining the events of the Show Cause Meeting will be forwarded to the Deputy Director for the Division of Construction Management (ECRM) for final concurrence.  The IOC shall contain the following:

·         The date of the Show Cause Meeting,

·         Those in attendance,

·         The major deficiencies discussed,

·         A summary of the corrective action to be taken to resolve the deficiencies, and

·         Tentative timeframe for the Follow-up Review to be held.

Rescission of Show Cause Notice

When the CAP is accepted by ODOT, Office of Contracts, the SCN is rescinded. The CAP remains in effect until a follow-up review can be conducted. Follow-up reviews will be conducted by the DEEOCC.

Follow-Up Reviews

A follow-up review is an extension of the initial review process to verify the contractor’s performance of corrective action and to validate progress report information.  Follow-up reviews shall only be conducted on those contractors where the initial review resulted in a finding of noncompliance and a show cause notice was issued.

A follow-up review should be conducted on the contractor’s workforce at the earliest possible opportunity, and if the contractor is in a declining workforce, at the earliest possible date of the construction season, whichever allows the contractor the best opportunity to implement its CAP. 

Follow-up reviews shall be conducted in the same manner as the initial review report, addressing only the deficiencies found during the initial review.  If the time-frame for the follow-up review and the contractor’s formal compliance review fall in the same calendar year the reviews may be combined.  Mark the review as both a follow-up and a formal compliance review.

Notice of pending follow-up review should be sent in the same manner as the original review notice with the following exceptions. The notice should address only the deficiencies found during the review.  Only send the contractor the sections of the Self-Analysis packet that are necessary for determining the corrective measures taken by the contractor to date. 

Request from the contractor only those items necessary for determining the corrective measures taken to date. 

It is not necessary to reassess aspects of the company which were in-compliance during the initial review.  Send the completed follow-up review, including a narrative summary to Central Office.

Follow-up review reports shall cover the following:

·         deficiencies identified during the review,

·         contractor’s corrective action plan,

·         contractor’s corrective measures to date, and

·         reviewer’s findings and recommendations.

The Office of Contract’s procedure for processing follow-up reviews is the same as the processing of the initial reviews, except that if the contractor is already in show cause and is found to still be deficient, Central Office will, within thirty (30) days, recommend that the contractor be brought to formal meeting.  The Deputy Director for the Division of Construction Management will immediately request a formal meeting with the Contractor and include the DBE Program Manager for the Office of Contracts.

Hearing Process

When such procedures as show cause issuance, conciliation conferences and formal meetings have been unsuccessful in bringing contractors into compliance within the prescribed 30 days, the Deputy Director for the Division of Construction Management (or other appropriate level) shall immediately recommend, through channels, that the Department of Transportation obtain approval from the FHWA for a formal hearing.  The contractor should be notified of the action.  At this hearing, the contractor will be given the opportunity to offer a rebuttal to the findings.

Recommendations to the FHWA for hearing approval shall be accompanied by full reports of findings and case files containing any related correspondence.  The following items shall be included with the recommendations:

·         Copies of all Federal and Federal-Aid contracts and/or subcontracts to which the contractor is party,

·         Copies of any contractor or subcontractor certifications,

·         Copy of show cause notice,

·         Copies of any corrective action plans, and

·         Copies of all pertinent Manpower Utilization Reports, if applicable.

SHAs through FHWA regional and division offices will be advised of decisions and directions affecting contractors by the FHWA Washington Headquarters, Office of Civil Rights, for the Department of Transportation.

Responsibility Determinations

In instances where requests for formal hearings are pending FHWA approval, the contractor may be declared a non-responsible contractor for inability to comply with the equal opportunity requirements.

SHAs shall refrain from entering into any contract or contract modification subject to E.O. 11246, as amended, with a contractor who has not demonstrated eligibility for government contracts and federally assisted construction contracts pursuant to E.O. 11246, as amended.       

Comprehensive Compliance Reviews

General

Comprehensive compliance reviews shall be implemented to determine employment opportunities on a county-wide and area wide rather than an individual project basis.

Methodology

Section of a Target Area 

In identifying the target area of a comprehensive compliance review (e.g. county area, or an entire State), consideration shall at least be given to the following facts:

·         Minority and female workforce concentrations.

·         Suspected or alleged discrimination in union membership or referral practices by local unions involved in highway construction.

·         Present or potential problem areas.

·         The number of highway projects in the target area.

Determine the review period.  After the target area has been selected, the dates for the actual onsite reviews shall be established.  It is suggested that the review period cover the previous calendar year.  Additional year-to-date information may be required, if necessary.

Contractor Notification

Those contractors selected for onsite review shall be sent a notification letter as described previously in this manual.                          

Onsite Reviews

Compliance reviews shall then be conducted in accordance with the requirements set forth in Section 230.409. 

Compliance Determinations

Upon completion of the comprehensive review, a compliance determination shall be made.  A show cause notice or compliance notification shall be sent (as appropriate) to the reviewed contractor.  The compliance determination shall be based on the contractor’s target area workforce (Federal and Federal-Aid).                

AAEVAL Final Determination Report

DEEOCC has 15 days to submit the completed AAEVAL Final Determination Report to Central Office.

Sample Corrective Action Plan

Deficiency 1:  Sources likely to yield minority employees have not been contacted for recruitment purposes.

Commitment: We have developed a system of written job applications at our home office which readily identifies minority applicants.  In addition to this, as a minimum, we will contact the National Association for the Advancement of Colored People (NAACP), the League of United Latin American Citizens (LILAC), Urban League, and the Employment Security Office within 20 days to establish a referral system for minority group applicants and expand our recruitment base.  We are in the process of identifying other community organizations and associations that may be able to provide minority applicants and will submit an updated listing of recruitment sources and evidence of contact by (Date).

Deficiency 2:  There have been inadequate efforts to locate, qualify and increase skills of minority and female employees and applicants for employment.

Commitment: We will set up an individual file for each apprentice or trainee by (Date) in order to carefully screen the progress, ensure that they are receiving the necessary training, and being promoted promptly upon completion of training requirements.  We have established a goal that at least 50 percent of our apprentices and trainees will be minorities and 15 percent will be female.  In addition to the commitment made to deficiency number 1, we will conduct a similar identification of organizations able to supply female applicants.  Based on our projected personnel needs, we expect to have reached our 50 percent goal for apprentices and trainees by (Date).

Deficiency 3:  Very little effort to assure subcontractors have meaningful minority group representation among their employees.

Commitment: In cooperation with the Regional Office of Minority Business Enterprise, Department of Commerce, and the local NAACP, we have identified seven minority owned contractors that may be able to work on future contracts we may receive.  These contractors (identified in the attached list) will be contacted prior to our bidding on all future contracts.  In addition, we have scheduled a meeting with all subcontractors currently working on our contracts.  This meeting will be held to inform the subcontractors of our intention to monitor their reports and require meaningful minority representation.  This meeting will be held on (Date) and we will summarize the discussion and current posture of each subcontractor for your review by (Date).  Additionally, as requested, we will submit a PR-1391 on (Date), (Date), (Date).  Finally, we have committed ourselves to maintaining at least 20 percent minority and female representation in each trade during the time we are carrying out the above commitments.  We plan to have completely implemented all the provisions of these commitments by (Date).

EEO/DBE/PW Compliance Enforcement on Local Public Agencies (LPA) Projects

DBE Subcontract Agreements/Purchase orders must be submitted to the DEEOCC for review and approval prior to the execution of the contract between the LPA and the Prime contractor.

The Contractor is required to use DBE firms certified by ODOT to perform the type of work subcontracted. A listing of certified DBE firms is available on the Office of Contracts’ website. The Contractor shall identify how they will meet the DBE / EDGE goal and in the event the Contractor is unable to meet the goal, the ODOT waiver process must be followed. The Contractor makes the waiver request first to the LPA.  The LPA forwards the request with recommended action to the DEEOCC.  The DEEOCC then makes recommendation and forwards the request to ODOT’s Office of Contracts. Only ODOT has the authority to grant a waiver.  The Prime Contractor must contract with DBE Subcontractors prior to the signing of the contract with the LPA. Each DBE subcontract or material supply agreement must be submitted to and approved by the ODOT DEEOCC prior to the DBE beginning work on the project.

Upon receipt of a C-92 (Request to Sublet) and the signed subcontract agreement or purchase order for a DBE firm that is to be used for goal, the DEEOCC is to verify that the firm is certified as a DBE through the UCP website (www.OhioUCP.org).  The DEEOCC is to verify that the DBE firm has been assigned the proper NAICS code(s) for the work that is detailed in the Subcontract Agreement or Purchase Order.  If it is for material supply, the DEEOCC must review the type of material that is to be supplied and compare it with the NAICS code assigned to the firm.  The DEEOCC must obtain information from the DBE firm via the LPA regarding whether any items listed are intended to be drop shipped.  NO DROP SHIPMENT CAN OCCUR WITHOUT PRIOR APPROVAL FROM ODOT.

If the DBE is a regular dealer only 60% of expenditures may be counted toward the DBE goal, provided that the supplier performs a commercially useful function in the supply process. The entire expenditure may be counted toward the DBE goal only if the DBE supplier is a manufacturer that produces the goods from raw materials or substantially alters them before resale.

Examine the amount that is to be supplied by the DBE Material Supplier - use "standard industry practice" guidelines to determine whether any amount may be dropped shipped.  If a portion is allowed to be dropped shipped, the remaining material must come from the DBE material supplier's yard or the DBE material supplier must use their own equipment to transport it from the manufacturer.

Any questions that you have should be directed to the LPA.  The LPA will then contact the DBE firm and relay the information to the DEEOCC

The LPA should contact the DBE BY E-MAIL DIRECTLY to get this information

Information obtained by the LPA will be forwarded to the DEEOCC.  The DEEOCC will then make a determination regarding approving or not approving the DBE firm.  The DEEOCC will advise in writing (via e-mail to LPA) of the approval or non-approval of the DBE firm.

The Quarterly Report of Payments Made to DBE firms must be submitted to the DEEOCC by the LPA on a quarterly basis.

DPWCs and DEEOCCs are required to perform a joint review of all active LPA projects.  Review of project documentation are to be conducted at a minimum of once per construction season per project.  

DPWCs and DEEOCCs are required to maintain a project folder for each LPA project working in their district.  This project folder will include the following:

1.        A copy of the project proposal/contract document

2.        Copies of all PW/EEO Questionnaires submitted monthly by the LPAs.

3.        Copies of all LPA project documentation reviews completed by the DPWC / EEOCC

4.        Copy of final Wage or DBE Affidavits of Subcontractor Payment for completed projects.

5.        Copies of all DBE sub-contract agreements and any other project related DBE goal attainment information.

The DPWCs /EEOCCs are to provide each LPA with any necessary forms, posters, payroll information, employee Prevailing Wage Notification forms, apprentice and trucking guidelines and CUF/DBE information.  These are to be distributed to the prime contractor by the LPA during the pre-con meeting.

Disadvantaged Business Enterprise (DBE)

General

The Disadvantaged Business Enterprise Program (DBE) is a legislatively mandated USDOT program codified in 49 CFR §26, et seq. The DBE Program applies to recipients of Federal-aid highway dollars expended on federally-assisted contracts.  The U.S. Congress established the DBE program in 1982 to ensure nondiscrimination in the award and administration of DOT-assisted contracts, help remove barriers to the participation of DBEs in DOT-assisted contracts, and assist the development of firms that can compete successfully in the marketplace outside of the DBE program.

Certification

The ODOT uses the certification standards of Subpart D of part 26 of the Code of Federal Regulations and the certification procedures of Subpart E of part 26 of the Code of Federal Regulations to determine the eligibility of firms to participate as DBEs in DOT-assisted contracts. To be certified as a DBE, a firm must meet all certification eligibility standards.

For information about the certification process or to apply for certification, firms should contact:        

Ohio Department of Transportation

DBE Services Section

Division of Construction Management, Mail Stop 4110

1980 W. Broad Street

Columbus, Ohio 43223

                                Tel. 1-800-459-3778

Goals, Good Faith Efforts and Counting Contract Goals

The ODOT will establish contract goals on those DOT-assisted contracts that have subcontracting possibilities. DBE goals are set on federally funded projects in excess of $500,000.00.

Good Faith Efforts

A determination of “good faith efforts” becomes necessary when at the time of contract award, the low bidder does not propose to meet the DBE project goal and if, during the execution of the contract, the planned subcontracts to DBE firms do not materialize.  The bidders must have exerted efforts that were of an intense, aggressive and sincere nature of the specific project far beyond any simple paper work exercise to demonstrate a good faith effort in achieving the project goal. It is the contractor’s responsibility to submit the information necessary for ODOT to ascertain compliance with the good faith efforts requirement.  The Department is responsible for submitting to the FHWA its conclusions and recommendations based on an analysis of the information.  

Good faith efforts should include, but not be limited to:

A.      Attending any pre-bid meetings at which DBE’s could be informed of contracting and subcontracting opportunities;

B.       Advertising in general circulation, trade association, and minority focus media concerning the subcontractor opportunities;

C.       Providing written notice to all certified DBE’s who have capabilities pertinent to the work of the contract that their interest in the contract is solicited.  This notice shall be in sufficient time to allow the DBE’s to respond to the written solicitation;

D.      Following up initial solicitations of interest by contacting DBE’s to determine with certainty if the DBE’s are interested;

E.       Selecting portions of the work to be performed by DBE’s in order to increase the likelihood of the DBE goals being achieved.  This may include, where appropriate, breaking down contracts into economically feasible units to facilitate DBE participation;

F.       Providing interested DBE’s with adequate information about the plans, specifications, and requirements of the contract;

G.      Negotiating in good faith with interested DBE’s.  The evidence of such negotiations should include the names, addresses, and telephone numbers of DBE’s that were considered, a description of the information provided regarding the plans and specifications for the work selected for subcontracting, and a statement as to why additional agreement could not be reached for DBE’s to perform the work;

H.      Not rejecting DBE’s as unqualified without sound reasons based on a thorough investigation of their capabilities;

I.         Making efforts to assist interested DBE’s in obtaining bonding, lines of credit, or insurance as required by the recipient or contractor;

J.        Making efforts to assist interested DBE’s in obtaining necessary equipment, supplies, materials, or other related assistance or services; and

K.       Effectively using the services of available minority community organizations; minority contractors’ groups; local, State, and Federal minority business assistance offices; and other organizations as allowed on a case-by-case basis to provide assistance in the recruitment and placement of DBE’s.

L.       Utilization of Bid Express Small Business Network to post sub-quote requests, located and advertise directly to certified and prequalified DBE’s, and produce a good faith form from the system.

Counting

When a DBE firm participates in a contract, only the value of the work actually performed by the DBE is counted toward DBE goals. DBE participation is counted toward goals via the following method:

A.      Count the entire amount of that portion of a construction contract that is performed by the DBE’s own forces. Include the cost of supplies and materials obtained by the DBE for the work of the contract, including supplies purchased or equipment leased by the DBE (except supplies and equipment the DBE subcontractor purchases or leases from the prime contractor or its affiliate).

B.       Count the entire amount of fees or commissions charged by a DBE firm for providing a bona fide service, such as professional, technical, consultant, or managerial services, or for providing bonds or insurance specifically required for the performance of a DOT assisted contract, toward DBE goals, provided the fee is determined to be reasonable and not excessive as compared with fees customarily allowed for similar services.

C.       When a DBE subcontracts part of the work of its contract to another firm, the value of the subcontracted work may be counted toward DBE goals only if the DBE’s subcontractor is itself a DBE.  Work that a DBE subcontracts to a non-DBE firm does not count toward DBE goals.

D.      Count expenditures to a DBE contractor toward DBE goals only if the DBE is performing a commercially useful function on that contract.

Good Faith Efforts When a DBE is Replaced/Substituted

A prime contractor may not terminate a DBE subcontractor (or an approved substitute DBE firm) without Prior written consent from ODOT Central Office. This includes, but is not limited to, instances in which a prime contractor seeks to perform work originally designated for a DBE subcontractor with its own forces or those of an affiliate, a non-DBE firm, or with another DBE firm.

The Prime contractor must demonstrate that it had good cause to terminate the DBE firm.  Good cause includes the following circumstances:

A.      The listed DBE subcontractor fails or refuses to execute a written contract;

B.       The listed DBE subcontractor fails or refuses to perform the work of its subcontract in a way consistent with normal industry standards. Provided, however, that good cause does not exist if the failure or refusal of the DBE subcontractor to perform its work on the subcontract results from the bad faith or discriminatory action of the prime contractor;

C.       The listed DBE subcontractor fails or refuses to meet the prime contractor's reasonable, nondiscriminatory bond requirements.

D.      The listed DBE subcontractor becomes bankrupt, insolvent, or exhibits credit unworthiness;

E.       The listed DBE subcontractor is ineligible to work on public works projects because of suspension and debarment proceedings pursuant 2 CFR Parts 180, 215 and 1,200 or applicable state law;

F.       ODOT has determined that the listed DBE subcontractor is not a responsible contractor;

G.      The listed DBE subcontractor voluntarily withdraws from the project and provides to ODOT written notice of its withdrawal;

H.      The listed DBE is ineligible to receive DBE credit for the type of work required;

I.         A DBE owner dies or becomes disabled with the result that the listed DBE contractor is unable to complete its work on the contract;

J.        Other documented good cause that ODOT determines to be just cause for termination of the DBE subcontractor. Provided, that good cause does not exist if the prime contractor seeks to terminate a DBE it relied upon to obtain the contract so that the prime contractor can self-perform the work for which the DBE contractor was engaged or so that the prime contractor can substitute another DBE or non-DBE contractor after contract award.

Before transmitting to ODOT its request to terminate and/or substitute a DBE subcontractor, the prime contractor must give notice in writing to the DBE subcontractor, with a copy to ODOT, of its intent to request to terminate and/or substitute, and the reason for the request.

The prime contractor must give the DBE five days to respond to the prime contractor's notice and advise ODOT and the contractor of the reasons, if any, why it objects to the proposed termination of its subcontract and why ODOT should not approve the prime contractor's action. If required in a particular case as a matter of public necessity ( e.g., safety), ODOT may provide a response period shorter than five days.

In addition to post-award terminations, the provisions of this section apply to pre-award deletions of or substitutions for DBE firms put forward by offerors in negotiated procurements.

When a DBE subcontractor is terminated, or fails to complete its work on the contract for any reason, ODOT requires that the prime contractor make good faith efforts to find another DBE subcontractor to substitute for the original DBE. These good faith efforts shall be directed at finding another DBE to perform at least the same amount of work under the contract as the DBE that was terminated, to the extent needed to meet the contract goal you established for the procurement.

ODOT will identify within the Contract a provision for appropriate administrative remedies that it will invoke if the prime contractor fails to comply with the requirements of this section.

The requirements of this section also apply to DBE bidders/offerors for prime contracts. In determining whether a DBE bidder/offeror for a prime contract has met a contract goal, ODOT will count the work the DBE has committed to performing with its own forces as well as the work that it has committed to be performed by DBE subcontractors and DBE suppliers.

Waiver Process for DBE Goal

It is the policy of the Ohio Department of Transportation that Disadvantaged Business Enterprises (DBEs) shall have equal opportunity to compete for and perform subcontracts which the Contractor enters into pursuant to this contract. The Contractor must use its best efforts to solicit bids from and to utilize DBE subcontractors with meaningful minority groups and female representation among their employees. Consequently, the requirements of Title 49 CFR Part 26 and Ohio Revised Code §5525.011 apply to this contract. The Contractor must ensure that the DBE subcontractor(s) is performing a “commercially useful function” as defined in CFR 26.55.

The percentage indicated on the front cover of the bid is the percent of the awarded Contractor's bid which must be subcontract to certified ODOT DBE firms. The percentage goal may be met if the awarded Contractor is DBE certified.

In order to be assured that the Contractor complies with this contract requirement the Contractor shall provide certified payrolls from its DBE subcontractors where appropriate. When the Contractor utilizes a service, for example trucking, to satisfy a part or its entire contractual goal, the Contractor, when requested, must provide a copy of each canceled check issued to the DBE service provider until the gal amount is reached. The Department shall total the amounts of the canceled checks and compare that total to the subcontract agreement by the parties and the C-92 issued to the Contractor for the work to be performed by the DBE subcontractor.

The Contractor must document the progress and efforts being made in securing the services of DBE subcontractors. In the event the Contractor is unable to meet the DBE Goal placed on this project, a request for a waiver of all or part of the goal may be made to the Office of Contracts. The written request must indicate a good faith effort was made to meet the goal and be sent to the Administrator, Office of Contracts, 1980 West Broad Street, Columbus, Ohio, 43223. There will be no extension of time for the project granted if the Contractor wishes to avail himself of this process. If an item of work subcontracted to a DBE firm is non-performed by the Department or the subject of an approved VECP, the Contractor may request a waiver for the portion of work excluded.

The Contractor must provide the following information and documentation when requesting DBE goal waiver:

1.        Dollar value and % of DBE goal. Dollar value and % of waiver request. 18 Project No. 110597.

2.        Signed copy of each subcontract or purchase order agreement between the prime and DBE subcontractor utilized in meeting the contract goal.

3.        Copy of dated written communication, fax confirmation, personal contact, follow up and negotiation with the DBE’s.

4.        Copy of dated written communication and/or fax confirmation that bidder solicited and provided DBE’s with adequate information about the plans, specifications and requirements of the contract in a timely manner to assist them in responding to a solicitation.

5.        Copy of dated written communication and/ or fax confirmation of each noncompetitive DBE quote that includes the dollar value of each reference item and work type.

6.        Copy of dated written communication and/ or dated fax confirmation of DBE’s that were not interested in providing a quote for the project.

7.        Documentation of all negotiating efforts and reason for rejecting bids.

8.        Documentation of good faith efforts (GFE) to meet the DBE subcontract goal, by looking beyond the items typically subcontract or consideration of subcontracting items normally performed by the prime as a way to meet the DBE goal.

The Administrator will review the submitted documentation and issue a written decision within ten (10) business days. The Contractor may request administrative reconsideration within 14 days of being informed that it did not perform a GFE. The Contractor must make this request in writing to the following official:

Ohio Department of Transportation

Attention: Administrator, Office of Contracts

1980 West Broad Street, Mail Stop 4110

Columbus, Ohio 43223

The reconsideration official will not have played any role in the original determination that the contractor did not document sufficient good faith effort.  As part of this reconsideration, the contractor will have the opportunity to provide written documentation or an argument concerning the issue of whether it met the goal or made adequate good faith efforts to do so. ODOT will send the contractor a written decision on reconsideration explaining the basis for finding that the contractor did or did not meet the goal or make adequate good faith efforts. The result of the reconsideration process is not administratively appealable to the US Department of Transportation. However, it is appealable to the Franklin County Court of Common Pleas.

Sanctions

The Ohio Department of Transportation will issue sanctions if the Contractor chooses not to request a waiver, the Contractor fails to comply with the contract requirements and/or fails to demonstrate the necessary good faith effort.  The Ohio Department of Transportation may impose any of the following sanctions:

1)       letter of reprimand;

2)       liquidated damages computed up to the amount of goal dollars not met;

3)       cross-withhold from future projects;

4)       contract termination and/or 19 Project No. 110597;

5)       other remedies available by law including suspension, revocation, and/or debarment.

Factors to be considered in issuing sanctions include, but are not limited to:

1)       the magnitude and the type of offense;

2)       the degree of the Contractor’s culpability;

3)       any steps taken to rectify the situation;

4)       the Contractor’s record of performance on other projects including, but not limited to:

a)        annual DBE participation over DBE goals;

b)       annual DBE participation on projects without goals;

c)        number of complaints the Ohio Department of Transportation has received from DBEs regarding the Contractor; and

d)       the number of times the Contractor has been previously sanctioned by the Department of Transportation; and

5)       whether the Contractor falsified, misrepresented, or withheld information.

Commercially Useful Function

General

The prime contractor is responsible for ensuring that those DBE’s committed to perform work under the contractor’s contract perform a commercially useful function (CUF).  Failure to fulfill this obligation will be considered a breach of the contract.

The prime contractor will be given credit toward the DBE contract goal only when the DBE performs a commercially useful function.  The ODOT will consider that a commercially useful function has been performed when (1) a DBE is responsible for the execution of a distinct element of the work by actually performing, managing and supervising the work involved in accordance with normal industry practice (except where such practices are inconsistent with the DBE regulations and these guidelines) and (2) the firm receives due compensation as agreed upon for the work performed.  Regardless of whether an arrangement between the contractor and the DBE represent standard industry practice, if the arrangement erodes the ownership, control and independence of the DBE or does not meet the commercially useful function requirement, the contractor shall receive no credit toward goal.

Management

The DBE must manage the work it has contracted.  The management shall include scheduling work operations, ordering equipment and materials (if materials are part of the contract), preparing and submitting payrolls and all other required reports and forms, and hiring and firing employees, including supervisory employees.  The DBE must perform the work of the contract with its own work force.  Unless precluded by State or Local policy, a limited portion of the work may be subcontracted (first or second tier subcontracting) consistent with normal industry practices.

The DBE must supervise the daily operations of the work contracted.  There are only two acceptable ways for the DBE to supervise the daily operations.  The DBE owner may act as superintendent and directly supervise the work, or a skilled and knowledgeable superintendent employed by and paid wages by the DBE must directly supervise the work.  If the latter is used, the DBE owner must be actively involved in making the operational and managerial decisions of the firm.  Basically, this means that all administrative functions must be performed by personnel responsible to or employed by the DBE at facilities or locations under the control of the DBE.

Workforce

The DBE shall supervise and perform the work of the contract with workers on its payroll and under the direct supervision of the DBE.  The DBE or his/her superintendent must, on a full time basis, supervise and control work on the contract.   The supervision of the contract work by personnel normally employed by another contractor or by personnel not under the control of the DBE constitutes failure to perform a commercially useful function.

Except in the instances defined below, the DBE shall perform its work with employees normally employed by and under the DBE’s control.  In all instances the DBE shall be responsible for its payroll and labor compliance requirements concerning all workers under its control.  Under the following conditions a DBE may use other means to perform the work:

A.      On a limited basis when a contract requires specialized knowledge (such as asphalt paving, soil cement, etc.), a DBE may be allowed to augment his or her work force with personnel which normally works for another firm.  In each case, the DBE shall request in writing and secure ODOT’s approval of the arrangement prior to commencing the work of the contract.

B.       If allowed by State or local policy, the DBE may enter into a subcontract under normally accepted industry practices.

C.       Prior to allowing any arrangement, the State shall ensure that:

1.        The arrangement is not designed to provide the DBE with the basic labor requirements of the contract.

2.        The arrangement is on a limited basis and not long term, repetitive or continuing.  Long term, continual, or repetitive use by a DBE firm of personnel primarily employed by a non-disadvantaged firm will be construed as an attempt to artificially inflate DBE participation and will not be allowed.

3.        Exclusive of the arrangement, the majority of the DBE’s work force and his or her superintendent/foreman are regular employees of the DBE.

4.        The arrangement should be indicative of normal industry practices and should not represent a significantly greater portion of the contract work than would be expected on the basis of normal industry practices.

Equipment

A DBE may lease equipment consistent with standard industry practice.  A DBE may lease equipment from the prime contractor, provided a rental agreement separate from the subcontract specifying the terms of the lease arrangement is approved by the ODOT prior to the DBE starting the work.  If the equipment is of a specialized nature, the lease may include the operator.  If this practice is generally acceptable within the industry, then the operator can remain on the lessor’s payroll.  The operation of the equipment should be subject to the full control of the DBE.  Such an arrangement should be for a short term and involve a specialized piece of heavy equipment readily available at the job site.

For equipment that is not specialized, the DBE is expected to provide the operator and to be responsible for all payroll and labor compliance requirements.

No credit will be given for the cost of equipment leased or rented and used in the DBE firm’s work when payment for those costs is made by a deduction from the prime contractor’s payment(s) to the DBE firm.

Materials

The DBE shall negotiate the cost, arrange delivery of, and pay for the materials and supplies required for the work of the contract.  Invoices for materials should be invoiced to the DBE firm and not to the prime contractor. The ODOT will periodically review invoices for materials to ensure compliance.

A prime contractor may occasionally find it necessary to pay suppliers directly for materials used by his/her subcontractors.  When such a payment arrangement is available to all subcontractor relationships and not restricted to just DBE’s, then counting the cost of materials actually incorporated into the project by the DBE subcontractor toward DBE participation will be allowable, provided the DBE participates in scheduling the delivery of the materials and is fully responsible for ensuring that the materials meet specifications.  When such payments are made by the prime contractor, it is recommended that the payments be made by jointly endorsable check signed by the prime and DBE.

No credit should be allowed toward the DBE goal for the cost of materials placed by a DBE subcontractor when payment for the costs is effected by making a deduction from the prime contractor’s payment to the DBE unless such transaction is clearly documented as part of a formal written agreement between the two parties and is approved by ODOT.

Trucking Operations

A.      To be certified as a DBE trucking firm, the firm must own at least one fully operational truck that is used on a day-to-day basis.  Where a hauling permit or license is required, a firm may qualify for certification if the firm owns the permit.  However, ODOT will ensure that if such firms do not own at least one truck, credit towards project goals is granted only for the fee the DBE firm retains for providing the hauling service.

B.       In order for the DBE project goals to be credited, DBE trucking firms must be covered by a subcontractor or a written agreement approved by ODOT prior to performing their portion of the work.

C.       In order to perform a commercially useful function, the DBE trucking firm is restricted to the same subcontracting limitation in effect for other contractors.  That is, the DBE trucking firm shall be required to perform the applicable required percentage of the work with his own trucks and personnel.  For example, if ODOT restricts all contractors from subletting or reassigning no more than 50% of the work to their contract, the same restriction would apply to DBE trucking operations.

D.      DBE trucking firms may rent or lease trucks from other sources, except from prime contractors to whom they are subcontractors, with the condition that only the vehicle is rented or leased and the DBE submits valid lease agreements on all trucks to be leased prior to the beginning of work.  All lease agreements, in order to be valid, must include the lessor’s name, the trucks to be leased, and the agreed upon amount or method of payment (hour, ton or load hauled).  Operators, fuel, maintenance and insurance for all leased trucks must be the sole responsibility of the DBE trucking firm.

E.       DBE trucking firms may utilize owner/operator trucks; however, the number of owner/operator trucks used may not exceed any limitations on subletting or reassigning the work specified in the State’s contract provisions.  All owner-operators must appear on the contractor’s or subcontractor’s payroll designated as owner/operators.  However, since contract wage rates are not applicable, the hours worked or wages paid may be reflected either on the payroll or on the record of payments to each owner/operator.

Encouraging Diversity, Growth & Equity (EDGE)

General

Encouraging Diversity, Growth & Equity (EDGE) is a contract assistance program designed to assist socially and economically disadvantaged businesses in Ohio. It was originally created by Executive Order 2002-17T in December 2002, and was codified in July 2003. EDGE establishes goals for state agencies, boards and commissions in awarding contracts. The program applies to procurements of supplies and services, professional services, information technology services, and construction, architecture and engineering. An EDGE participant must be a small socially and economically disadvantaged business enterprise owned and controlled by U.S. citizens who are Ohio residents. A business enterprise may qualify if the owner meets the criteria for both social and economic disadvantage.

Goals

EDGE goals are considered on state funded projects in excess of $250,000. 

Waiver Process for Edge Goal

If not EDGE certified, the Contractor must document the progress and efforts made in securing the services of EDGE subcontractors/suppliers. In the event the Contractor is unable to meet the EDGE Goal placed on this project, a request for a waiver of all or part of the goal may be made to the Office of Contracts. The written request must indicate a good faith effort was made to meet the goal and be sent to the Administrator, Office of Contracts, 1980 West Broad Street, Columbus, Ohio, 43223.

There will be no extension of time for the project granted if the Contractor wishes to avail itself of this process. If an item of work subcontracted to an EDGE firm is non-performed by the Department or the subject of an approved VECP, the Contractor may request a waiver for the portion of work excluded.

The Contractor must provide the following information and documentation when requesting EDGE goal waiver:

A.      Dollar value and % of EDGE goal. Dollar value and % of waiver request.

B.       Signed copy of each subcontract or purchase order agreement between the prime and EDGE subcontractor/supplier utilized in meeting the contract goal.

C.       Copy of dated written communication, fax confirmation, personal contact, follow up and negotiation with the EDGE firm.

D.      Copy of dated written communication and/or fax confirmation that bidder solicited and provided EDGE with adequate information about the plans, specifications and requirements of the contract in a timely manner to assist them in responding to a solicitation.

E.       Copy of dated written communication and/ or fax confirmation of each noncompetitive EDGE quote that includes the dollar value of each reference item and work type.

F.       Copy of dated written communication and/ or dated fax confirmation of EDGE firms that were not interested in providing a quote for the project.

G.      Documentation of all negotiating efforts and reason for rejecting quotes from EDGE firms.

H.      Documentation of good faith efforts (GFE) to meet the EDGE subcontract goal, by looking beyond the items typically subcontract or consideration of subcontracting items normally performed by the prime as a way to meet the EDGE goal.

The Administrator will review the submitted documentation and issue a written decision within ten (10) business days. The Contractor may request administrative reconsideration within 14 days of being informed that it did not perform a GFE. The Contractor must make this request in writing to the following official:

Ohio Department of Transportation

Attention: Office of Contract Administration

1980 West Broad Street Mail Stop 4110

Columbus, Ohio 43223

The reconsideration official will not have played any role in the original determination that the Contractor did not document sufficient good faith effort. As part of this reconsideration, the Contractor will have the opportunity to provide written documentation or an argument concerning the issue of whether it met the goal or made adequate good faith efforts to do so. ODOT will send the Contractor a written decision on reconsideration explaining the basis for finding that the Contractor did or did not meet the goal or make adequate good faith efforts. The result of the reconsideration process may be appealed to the Franklin County Court of Common Pleas.

Affidavit of Subcontractor Payment

The Ohio Revised Code 123.152, requires the Ohio Department of Transportation (ODOT) to monitor and verify that work subcontracted to Encouraging Diversity, Growth and Equity (EDGE) firms is actually performed by the EDGE firms. The affidavit seeks to verify actual payments made to EDGE firms on the project. Each EDGE firm must verify the actual payment amount.

The blank spaces in the affidavit must be filled in correctly, where indicated. The affidavit must be signed by the Contractor and subcontractor, or by the subcontractor and EDGE subcontractor, if applicable. By signing the affidavit, the noted firm agrees that the payment amount recorded is true and accurate as of the payment time period.

Completed and signed affidavit shall be mailed to the Ohio Department of Transportation, Office of Contracts, DBE Services section, 1980 West Broad Street, Columbus, Ohio 43223.

Sanctions

The Ohio Department of Transportation will issue sanctions if the Contractor chooses not to request a waiver, the Contractor fails to comply with the contract requirements and/or fails to demonstrate the necessary good faith effort.

The Ohio Department of Transportation may impose any of the following sanctions:

1)       letter of reprimand;

2)       liquidated damages computed up to the amount of goal dollars not met;

3)       cross-withhold from future projects;

4)       contract termination; and/or

5)       other remedies available by law including suspension, revocation, and/or debarment.

Factors to be considered in issuing sanctions include, but are not limited to:

1)       the magnitude and the type of offense;

2)       the degree of the Contractor’s culpability;

3)       any steps taken to rectify the situation;

4)       the Contractor’s record of performance on other projects including, but not limited to:

a)        annual EDGE participation over EDGE goals;

b)       annual EDGE participation on projects without goals;

c)        number of complaints the Ohio Department of Transportation has received from EDGE firms regarding the Contractor; and

d)       the number of times the Contractor has been previously sanctioned by the Department of Transportation; and

5)       whether the Contractor falsified, misrepresented, or withheld information

107.10 Protection and Restoration of Property

All properties to be utilized by the Contractor outside the project right-of-way must be cleared for all environmental resource impacts prior to the start of work. The project right-of-way consists of the right-of-way the project is being constructed upon. Environmental resource features pertinent to the construction activity should be shown in the contract documents. The Contractor is responsible for evaluating all impacts on environmental resources outside the project right-of-way.

Environmental resources include, but may not be limited to:

1.        Cultural resources.

a.        Buildings, structures, objects, and sites eligible for or listed on the National Register of Historic Places.

b.        Historic or prehistoric human remains, cemeteries, and/or burial sites (pursuant with ORC 2909.05 and 2927.11).

2.        Ecological resources.

a.        Wetlands.

b.        Streams.

c.        Wooded areas with trees to be removed in excess of 8 inches diameter at breast height.

3.        Public lands.

a.        Lands meeting the criteria of 49 U.S.C. 303, 23 CFR 771.I35: 4(f).

b.        Lands meeting the criteria of 16 U.S.C. 4601-4, 36 CFR59.1: 6(f).

4.        FEMA mapped 100 year floodplains. 

5.        Hazardous waste areas.

All areas proposed to be utilized by the Contractor outside the project construction limits shall be reviewed by environmental contractor(s) that are prequalified by the Department for each environmental resource.  Have the consultant(s) certify that the proposed site to be utilized for the Contractor will not impact:  

·         Cultural resources.

·         Ecological resources.

·         Public lands.

·         FEMA mapped 100 year floodplains. 

·         Hazardous waste areas.

Provide all documentation and the consultant certification to the Department’s Office of Environmental Services.

107.11 Contractor’s Use of the Project Right-of-Way or Other Department Property

General

This section compiles the requirements for sections 104.03 Rights in and Use of Materials Found on the Work, 105.16 Waste and Borrow Areas, and 105.17 Construction and Demolition Debris.

All of the environmental requirements in 105.16 Waste and Borrow Areas and 105.17 Construction and Demolition Debris apply to on-site locations.  The exceptions to these requirements are detailed in 105.16 Waste and Borrow Areas of this manual.

Borrowing and/or Wasting on the Right-of-Way (107.11.A)

Under 104.03, Rights in and Use of Materials Found on the Work, the Contractor has the right to all materials found in the contract work.  However, the Contractor does not have the right to materials outside the plan work.  For example, the Contractor does not have the right to rock found outside the cross-section work.  On the other hand, if the Contactor finds rock within the cross-section, they can use the rock for other items of work.

In order for the Contractor to have the “fee free” right to the material, the Designer needs to detail borrow and/or waste areas in the plans prior to bid.  If the locations are not shown and the Contractor receives approval to borrow and/or waste on ODOT property, then a charge of $ 0.50 per cubic yard will be assessed.  When borrow and/or waste areas are shown on the plans, there is not a charge for the material.

This requirement was put into the specifications to even the bidding for all contractors.

Approval for Borrowing and/or Wasting on the Right of Way

All borrow and waste location requests on the right-of-way need the District Office of Production approval.  The guidance document for the approval can be found at the following link:

http://www.dot.state.oh.us/roadwayengineering/L&D Vol I/Waste_Borrow_4-30-02.pdf

The District Office of Production will look at the following during the approval process:

·         Safety grading and clear zone.

·         Sight distances.

·         Future expansion.

·         Environmental regulations (404, 401, NPDES, etc.), (See Environmental Approval in 105.16, Waste and Borrow Areas, of this manual).

·         Public commitment.

·         Effects on utilities.

·         Stability (See Stability and Settlement in 105.16, Waste and Borrow Areas, of this manual).

As this process evolves, there may be changes to this criterion.

Portable Plants within the Project Limits (107.11.B &107.11.C)

The use of ODOT property for portable plants is restricted under this section of the specifications.  Production may detail potential locations on the plans.  If the locations are detailed on the plans, then the location is fee free.  If the location was not shown in the plans and the site is approved by the District for use, then the Department will consider this change a Value Engineering Change Proposal.

There are four requirements detailed in C&MS 107.11.C that must be met by the Contractor. 

·         The Contractor’s efforts to comply with the noise ordinances (107.11.C.1) need approved by the District Environmental Coordinator.

·         The EPA permits (107.11.C.2) need approved by the District Environmental Coordinator. 

·         The written certification that the plant will supply material only for the project (107.11.C.3) must be submitted to the Engineer.

·         The traffic plan (107.11.C.4) needs approved by District Planning and Engineering.

Equipment Storage and Staging (107.11.D)

The “fee free” use of project right-of-way for staging, equipment storage, and/or office site is granted in this section.

The only restrictions are that these locations do not interfere with the work and are not otherwise restricted in the contract documents.

Documentation Requirements - Waste and Borrow Sites (105.16, 105.17 and 107.11)

It is the intent of this section to recommend minimum documentation and critical inspection requirements for the above sections.  All of the following documentation requirements need recorded in the project daily reports.  References to the appropriate laws, specifications, and proposals and plan notes or details for all the inspector reports are required.  Specifications or other requirements waived by the Engineer shall be noted on the daily diaries.

Regulated waste work may be inspected and documented by the District Environmental Coordinator (DEC), District Hazardous Waste Coordinator (DHWC), or Regulated Waste Project Engineer (RWPE).  Inspection required by these individuals is denoted below.

In addition, clearances or reviews that need to be performed by other offices or individuals in the Department will be denoted.  This includes the District Office of Production (DOP) and the Office of Geotechnical Engineering (OGE).

1.        Contractors operational plan approval.

2.        Stability and settlement (OGE).

3.        NPDES permit and erosion control (DOP).

4.        404 and 401 permit or evaluation (DEC).

5.        Floodplain clearance (DEC).

6.        Cultural resource clearance (DEC).

7.        Open burning permit (DEC).

8.        Any disposal requiring manifesting (DEC, DHWC, or RWPE).

9.        Construction and demolition debris.

a.        Determination if clean, hard fill or construction debris.

b.        Quantities and locations of material leaving and filling on the site.

c.        Seven day notice to the local board of health or OEPA.

d.        Record quantities going to the C & D landfills.

                                                               i.      Manifest properly (DEC, DHWC, or RWPE)

10.     Landscape Wastes.

a.        Record quantities and locations of materials leaving and buried on-site.

b.        Record what happened to the rest of the material.

c.        Recycled.

d.        Reused.

                                                               i.      Manifest Properly (DEC, DHWC, or RWPE).

11.     Open Burning.

a.        Obtain a copy of the permit.

b.        Is the smoke causing a hazard?

c.        Is the burning at the correct time?

d.        Is an air curtain used?

e.        Are there any fire hazards?

12.     Proper disposal of concrete waste.

a.        Three-foot cover on-top.

b.        Eight-foot cover on the sides.

c.        Core mixed with 30 percent soil.

d.        Is the fill stable?

13.     Contractor use of the right-of-way.

a.        Approval (DOP).

b.        All clearances. See No. 3 through 7 above.

c.        Fifty cents a cubic yard or free.

d.        Portable plant approval (DOP).

14.     Cross-section the site if required for payment.

a.        Wasting.

b.        Borrowing.

15.     Owner’s permission statement.

a.        Material not the Departments.

b.        ODOT not a part of the agreement.

c.        ODOT held harmless.

16.     Restoration.

a.        Temporary BMP removal.

b.        Site clean-up.

c.        Final acceptance.

108 Prosecution and Progress

The purpose of this section is to discuss tools available to the Department for use in tracking the Contractor's progress and timely completion of the project.

Following the signing of a contract for a construction project, the District will contact the Contractor and schedule a Preconstruction Meeting. On or about that time, an Engineer will be chosen by the Department for that project.

 Once the Engineer is chosen, it is the responsibility of that individual or team to review all of the project documents and terms of the contract prior to the Preconstruction Meeting. Special attention must be paid to the following items:

·         Plan Notes.

·         Completion date.

·         Interim completion dates.

·         Special uses of "As per Plan" reference items.

·         Proposal notes and supplemental specifications.

·         Phasing requirements.

·         Special provisions.

·         Addenda.

A check of the status of utility relocation (must be performed immediately as to avoid delays to the start of the project).

Partnering (108.02)

The purpose of Partnering is to develop a proactive effort and spirit of trust, respect, and cooperation among all stakeholders in a project.  Project personnel are to adopt the Partnering concepts on each project.  Self-facilitated Partnering is the standard on all Projects and is to be performed by the Engineer and Contractor.  Once the contract is awarded, the DCA, or designee will initiate Partnering activities by discussing with the Contractor how Partnering will be implemented on the Project. At this stage, the DCA, the Engineer, and Contractor will identify and define major issues and project concerns and share relevant information to help determine the scope of the partnering efforts and to establish the agenda for the Preconstruction Meeting.   Partnering will be an important part of the Preconstruction Meeting and shall have its own agenda with specific time set aside to develop the necessary partnering protocols.

Preconstruction Meeting (108.02.A)

The purpose of the Preconstruction Meeting is to review the various items of work as set forth in the detailed construction plans, bid proposal, specifications, and the Contractor's work schedule and to establish the Partnering relationship among project personnel. Those items to be discussed are the necessary utility adjustments, availability of right-of-way, maintenance of traffic, and the Department's responsibility for the interrelated activities so that all concerned might have a better understanding of the problems involved and thus be able to coordinate the project.

The rationale of employing a thorough Preconstruction Meeting is pervasive as regards claim avoidance in that it seeks to uncover problems at a time when there is the greatest flexibility available for their solution and with the least disruption to the project. It is designed to create, for all parties, an overview of the conduct of the work and flush out any misconceptions or erroneous assumptions.  By including Partnering as an important piece of the Preconstruction Meeting, the environment of open communication, trust, and cooperation necessary for effective and efficient contract performance is established. 

Understandings reached at meetings of this nature have resulted in improved relations and coordination of interrelated activities by all concerned.

The Preconstruction Meeting really is the place to establish communication, voice and discuss intentions, discuss concerns, and lay out the road map and rules for the conduct of the project.

A preliminary study of the project shall be made in advance of the meeting in order that the pertinent problems involved are known.  Also, prior to the meeting, the DCA shall coordinate with the Contractor to determine whether the Initial Partnering Session will be a component of the Preconstruction Meeting or held as a separate session.

After the Contractor has contacted the District Construction Administrator about setting up the Preconstruction Meeting, both parties shall invite all important stakeholders to the Preconstruction Meeting, including but not limited to:

·         Subcontractors.

·         Key suppliers.

·         State personnel, including the Engineer and staff, Utilities Coordinator, EEO Coordinator, Design Engineer, Traffic Engineer, Test Engineer, Public Information Office, County Manager, District Environmental Coordinator, and all parties involved with the preparation of the plans.

·         Utility companies with facilities located within the right-of-way, including all railroads and local park boards.

·         Maintaining agency.

·         Regional Transit Authority.

·         Parties funding project including FHWA/County/Local.

At the Preconstruction Meeting, the Project Engineer must obtain a list of contacts for all parties involved with the project. This list will be useful in the future for timely resolution of problems which surface during the project construction. These contacts should also be invited to attend the progress meetings held on-site once the project begins.

Ensure that required items listed in C&MS 108.02, which the contractor needs for the Preconstruction Meetings, are obtained and reviewed in addition to the items below:

·         List of haul roads.

·         Executed contractor signature authorization form (CA-D-10).

An agenda should be used at every Preconstruction Meeting.  It is recommended that the standard Preconstruction Meeting Agenda/Minutes form be utilized and formatted as needed for each project.  The checklist below represents the more common items that should be included in the agenda.

Review of planned project work:

·         Right-of-way issues.

·         Utility relocations.

·         Railroad coordination, including any agreements between the Contractor and a railroad.    

·         Any pending change orders or contemplated extra work.

 Information from the Contractor:

·         State, in general, work procedures, type of equipment to be used, and the number of working shifts to be used.

·         State the haul roads (C&MS Section l05.l3) and waste and borrow areas (C&MS Section l05.16) to be used.

·         Submit documentation itemizing the payroll taxes that the project will incur under C&MS l09.04.A and 109.05.C.2 if extra work is added to the project.

·         Submit documentation stating the method of paying fringe benefits to workers required by prevailing wage law.

·         Requests for clarification of any questionable aspects of the contract or project site conditions.

Documentation of the Preconstruction Meeting:

·         A list of meeting attendees and their affiliation.

·         Written minutes using Preconstruction Meeting Agenda/Minutes.

·         A tape recording of the conference can be used as a back-up.

·         Record the date of the Preconstruction Meeting in SiteManager Key Dates/Critical Dates screen.

Initial Partnering Session (108.02.B)

The DCA or designee, the Engineer, and the Contractor will jointly conduct the Partnering meeting.  The meeting will cover administrative requirements.  Document the meeting minutes on the Initial Partnering Session Agenda/Minutes form. The Engineer and the Contractor should review the list of stakeholders and send an invitation to all stakeholders involved in the project.  At this session, all parties should:

·         Discuss and obtain agreement on the meaning of any ambiguities identified in the contract documents include the proposal, any special provisions, and any general plan notes.

·         Establishment of an RFI process, specifically to whom an RFI must be addressed, acceptable format (letter, e-mail), and standard response time.

·         Empower the district staff to quickly resolve issues in steps l or 2 of the Dispute Resolution and Administrative Claims Process.                                                                                                

·         Review the chains of commands of the Department and Contractor.

·         Obtain understanding and agreement that ignoring an issue or making no decision is not acceptable.

·         Individuals are not expected to make a decision with which they are uncomfortable, but should escalate upward in the dispute resolution process.

·         Both parties should agree to finalize-as-you-go.

·         Obtain contact information for all stakeholders.

Distribute the meeting minutes to all stakeholders for review and commitment to the plans developed.

Facilitated Partnering (PN 111)

Proposal Note 111 sets forth the requirements and compensation for Facilitated Partnering.  Facilitated Partnering is used on select projects that are typically over $5 million, complex in nature, project duration over a year, a high diversity of stakeholders, pubic involvement, coordination issues, and a high extent of utility and railroad involvement.

With input from the Engineer, select a partnering facilitator from the ODOT prequalified list located on the Division of Construction Management’s Partnering website. Ensure the Facilitator teaches all partnering sessions according to the Department’s Partnering Facilitator Standards and Expectations manual.

Payment

·         A Special Item, Lump Sum, will be furnished in the Proposal to pay for the services of the facilitator.

·         Submission for Compensation. The facilitator shall submit to the Contractor actual invoice costs.

·         Facilitator Compensation. After a review and verification by the Contractor and Department of the facilitator’s submission for compensation, the Contractor shall pay the facilitator the fees earned.

·         Contractor Reimbursement. The Department and the Contractor shall bear the costs and expenses of the facilitator and venue equally.

·         The facilitator chosen by the Department and the Contractor shall be compensated at a maximum rate of $3,500 for the Initial Partnering Session.

·         The facilitator shall be compensated at a rate maximum rate of $1,500 for the Partnering Update Sessions.

·         If the Department’s costs of the Facilitated Partnering item exceed the fixed amount, the Department will continue to pay its share of the actual invoice costs of the item by processing a change order.

Specific attention should be paid to coordinating the Partnering Specifications in C&MS 108.02, Dispute Review Board (PN 108), and/or the Dispute Review Advisor (PN 109) processes in order to maximize the effectiveness of the Partnering efforts.

Progress Meeting (108.02.C)

Progress meetings are very productive tools for enhancing communication, discussing issues, and solving problems, thus, furthering progress on the project. The Engineer must invite the appropriate personnel to attend the progress meetings. The status of the project must be discussed with the Contractor.  Before the progress meetings, the Engineer should prepare an agenda.  An agenda should cover all items pertinent to the success of the project and be similar in format to the standard Progress Meeting Agenda/Minutes form. Agenda items to be considered include:

·         The Partnering relationship on the project.

·         The progress towards the goals established in the Preconstruction Meeting.

·         Report any issues that have been discovered on the project and how resolution has been approached, including timing with respect to the raising and consideration of the claims at all levels.

·         Report the implementation plans for risk mitigation and opportunity enhancement.

·         Identify additional risks and opportunities.

·         Develop any additional, necessary strategies to improve project performance.

Report all findings in the project minutes with copies sent to the senior personnel team for the review. 

Post-Milestone Meeting (108.02.D)

Contemplate holding a Post-milestone Meeting as a separate meeting on any multi-year, multi-phase project or projects with critical items of work or milestone dates.  Review the schedule with the Contractor and determine whether or not a Post-Milestone Meeting should be held separately from a regularly scheduled Progress Meeting.  In cases where Post-Milestone Meetings are held, coordinate with the Contractor to develop an agenda and consider reviewing the goals set forth at the Initial Partnering Session.  Review the stakeholders list for the project to and consider inviting all parties.

Partnering Monitoring (108.02.E)

Consistently monitor the progress of the Partnering Relationship based on the goals decided during the Initial Partnering Session.  Determine whether to use the standard survey available online through the Division of Construction Management’s Partnering website or to develop a different measure. The standard survey title, “Partnering Monitoring Survey,” can be found at the following link:

http://www.surveymonkey.com/s/ODOT_Partnering_Monitoring_Survey

When project personnel choose to utilize the standard survey, the Engineer should coordinate with the Central Office Partnering Coordinator to ensure the results are distributed for review at the Progress Meetings.

Mitigation and Notice (108.02.F)

As issues arise throughout the course of the work, all parties have the shared contractual and legal requirement to mitigate the issue, whether caused by the Department, Contractor, third-party, or intervening event.

Most construction contracts, including ODOT’s, include a requirement for the Contractor to provide prompt notice of circumstances that may require a revision to the contract documents. This notice of the existence of a potential change to the contract is required before the Contractor begins any changed or extra work. Failure to give prompt notice could defeat an otherwise properly documented claim.

The purpose of requiring early notice is so the owner has the option of proceeding with the work, redesigning the work, and/or otherwise reducing the effect of a claimed event. Early notice allows the owner the opportunity to begin keeping careful and specific records of the Contractor’s activities, manpower, equipment, and materials which are related to the claim.

Dispute Resolution and Administrative Claims Process (108.02.G)

General

ODOT, by the nature, volume, and complexity of the work which it does, is subject to claims by Contractors who perform the work. Documents that make up the contract consist of the proposal, specifications, and the plans, which together are referred to as the stated terms.  There are certain terms which are not stated in the contract documents. These are known as implied terms. For instance, there is an implied warranty that the plans and specifications are free from defects, and unless otherwise stated, there will be safe and continuous access to all areas within the project's boundaries. Claims arise from both stated and implied terms.

Issues, Disputes, and Claims

The words issue, dispute, and claim are often used interchangeably, but the words, as used in ODOT contract language, do have different meanings. An issue is defined as a vital or unsettled matter, which arises during the course of the work and can be caused by the Department, Contractor, third-party entity, or some other intervening circumstance.   A reasonable attempt must be made to resolve all issues according to all legal and contractual requirements.  An issue rises to the level of a dispute when all efforts to mitigate have led to each party having a difference of opinion on the matter. 

A dispute is a disagreement and/or a difference of opinion between ODOT personnel and the Contractor. A dispute  matures into a claim when an issue in dispute cannot be resolved at the Project or District level. A dispute officially becomes a claim when the Contractor files a Notice of Intent to File a Claim or a Notice of Intent to Appeal to the Dispute Review Board. At this time, the Contractor will be asked to certify the claim. The Contractor must certify under oath, by signing in front of a notary, that the claim is made in good faith, is accurate and complete, and represents the actual costs incurred both in time and money.

On Federal Oversight projects, once the dispute becomes a claim, ODOT is responsible for providing all subsequent documentation involving that claim to the Federal Highway Administration. The Department’s Claims Coordinator is responsible for these submittals.

Who Can File a Claim?

The only entity that can assert a claim against the Department is the Prime Contractor.  If the project is being performed by a joint venture, then only the joint venture can assert a claim.  Do not discuss a dispute with a subcontractor without having the Contractor’s responsible representative present.

Elements of a Claim

Every claim has two distinct elements:

Entitlement is the theory under which the Contractor asserts the claim. Examples include differing site conditions, conflict between plans and specifications, delays, etc.

Damages are the monetary and/or time impacts incurred by the Contractor, which are a direct result of the claim event.

Types of Claims

Certain types of disputes by their nature are those which are most likely to result in a claim. The most common claims deal with:

Interpretation of contract documents (102.05, 102.07, 104.01, 105.01, 105.04).

Differing site conditions (102.05, 102.07, 104.02.B).

Extra work (104.02.F, 109.05).

Repair of defective work/material (105.01, 105.03, 105.10, 105.11, 106.07, 107.15).

Suspension of work/failure to continue work (104.02.C, 104.02.G.3, 108.05, 108.08).

Acceleration (109.06).

Significant changes in the character of the work (104.02.D, 104.02.E).

Interference by/cooperation with third-party (105.07, 105.08, 107, 108.04).

Inspection (over/under) (105.01, 105.03, 105.09, 105.10, 105.11, 106.03, 106.07, 109.12).

Inefficiencies (109.07).

Quantity variations (102.04, 109.01, 109.04).

Delays (108.06, 109.05.D).

Proof of Claim

The Contractor has the burden of proving both entitlement and damages. If the Contractor cannot prove entitlement, the claim must be denied. Likewise, if the Contractor proves entitlement, but cannot prove that it incurred any cost and/or time impacts, the claim must be denied.

Claim Cost Approaches

Contractors utilize various approaches to present the damages associated with a claim. Below are the most common:

Total Cost: In this method the Contractor submits the total cost to perform the work. This method presupposes that there are no contractor inefficiencies or unanticipated contractor costs. ODOT rarely accepts this approach.

Modified Total Cost: In this method the Contractor submits his total cost to perform the work and then deducts an agreed upon contractor inefficiency. A little better than the total cost method, but still not ODOT friendly.

Force Account (Time and Materials) (109.05 C): Based on actual records and actual contractor costs. Cumbersome to assemble and check, but has a certain essential fairness built in. Mark-ups and determination of costs defined in the specifications.

Measure Mile: Force Account records are kept for a specified length of time and the cost is calculated. This production rate and cost is then assumed constant throughout the rest of the work. Applicable only when a large quantity of similar extra work is to be done for an extended period of time.

Agreed Unit Price/Agreed Lump Sum (109.04 B): Uses unit prices agreed upon by the Contractor and ODOT. Good for ODOT since ODOT has large amounts of data concerning unit prices. The Office of Estimating is available to provide expertise on work items not available in database.

Analyzing a Claim

The following step-by-step process should be used to analyze a claim.

Did the Contractor give the required Early Written Notice (108.02.F)?

ENTITLEMENT:

What is the Contractor’s theory of entitlement?

What do the contract documents say?

Determine the actual sequence of events giving rise to the claim.

Identify each specific claim issue.

What is the position of both sides on each issue?

If delay related:

o    Did the claim circumstance delay work on the critical path (108.06.A)?

o    Is it an excusable or non-excusable delay (108.06.B through 108.06E)?

o    Is it a compensable or non-compensable delay (108.06.B through 108.06.E)?

o    Were any of the delays concurrent (108.06.F)?

DAMAGES:

Has the Contractor proven the damages directly relate to the issue being claimed?

Do ODOT records agree with the Contractor’s submitted documentation?

Does the Contractor’s cost submittal meet the guidelines for extra work (109.05)?

Are the damages reasonably in line with industry standard costs for the same work? If not, is there a reason why?

Did the Contractor mitigate the monetary and time damages?

Importance of Project Documentation

It is impossible to overemphasize the need for consistent, complete, and accurate project documentation. Contemporaneous records, documents written at the time of the event, normally carry more weight in claims decision-making than records written up at the time the claim is submitted for analysis. Project documentation must be clear and legible, written in real time, be a regular practice, and be sufficiently detailed to describe the writer’s thoughts. Examples of project documentation that are routinely used to support a claim position include pre-bid, pre-construction, and progress meeting minutes; daily diaries; force account records; idle equipment records; correspondence, including e-mails; RFI’s; transmittals/submittals; project schedule and changes; phone conversations; and photos and videos.

Claim Avoidance

Claim avoidance, at its most basic level, is accomplished by removing or lessening the factors which contribute to claims. Discussed below are some of the methods used by the Department:

Prequalification and post project assessment of contractors:

o    Qualified, capable contractors with the resources (i.e., qualified superintendents, capacity to maintain schedule, quality work) to undertake a project can lessen the factors which lead to claims.

Constructability Review: The Department has instituted Constructability Reviews which occur at the District level. The review team is generally designated by the DCA. The review team will:

o    Review general notes and special provisions.

o    Review plans.

o    Personnel should walk the project paying particular attention to:

§  Right of way encroachment or obstructions.

§  Utilities.

§  Drainage.

§  Pavement or bridge condition (i.e., heaving, cracking, deterioration).

§  Sediment and erosion problems and other geological features.

§  Stream and stream diversions.

§  Railings and signs.

§  Joint conditions.

§  Impact on signals.

§  Quantities.

o    Listen to operations personnel. They know existing problems.

o    Look for the obvious discrepancies in location, missing information, obstructions, conditions, or quantities.

Change Order Review: At the time a change order is written, its creator is required to choose a reason code for each reference item included on that change order. If the chosen reason code is (Plan) Error or Omission, the change order is targeted for review by the Department’s Change Order Review Team. This team reviews these change orders for recurring problems, recommends steps for correction, and provides this information to the District Planning and Engineering Office. This team also identifies changes caused by plan errors or omissions on which ODOT may pursue compensation for the cost of the required change from the designer of the plan.

Claims Tracking: Disputes and claims are studied by ODOT, enabling clarification and/or correction of the contract documents in order to avoid future disputes and claims.

Claims Management

The Department takes a proactive approach which seeks to avoid disputes and claims. In the event disputes or claims do arise, orderly procedures are in place to assist with managing the claims.

ODOT’s Dispute Resolution and Administrative Claims Process is a step-by-step sequence of events which occur following the Contractor’s Early Notice submittal described in C&MS 108.02.F. This notice is required when the Contractor discovers a circumstance that may require a revision to the contract documents or may result in a dispute.

C&MS 108.02.G sets forth the details of each of the three steps of the Dispute Resolution and Administrative Claims Process. These three steps include On-Site Determination, District Dispute Resolution Committee, and Director’s Claims Board. C&MS 108.02.G also sets forth specific submittal timeframes at each step which must be met by both the Contractor and ODOT personnel to move a dispute toward resolution. These timeframes are included as recognition that: (1) the Contractor deserves timely responses and (2) it is easier to resolve a dispute when the events are clear in everyone’s mind rather than allowing an issue to remain until the finalization stages of a project.

The Dispute Resolution and Administrative Claims Process (C&MS 108.02.G) is the default process and is included on all projects except those that use the Dispute Review Board Process (PN108) or utilize a Dispute Review Advisor (PN 109).  The applicable process must be followed by the Contractor in order to seek additional compensation or contract time.

Dispute Resolution Board Process (PN 108)

The Dispute Resolution Board (DRB) Process is used on select projects that are typically over $20 million and/or of a highly technical nature.  Proposal Note 108 (PN 108) provides that a Dispute Resolution Board (DRB) be established prior to the start of construction of a project and exists through the life of that project. A DRB is comprised of three members, each with a minimum of 10 years’ experience in construction, contract administration, and dispute resolution techniques. One member is chosen by the Contractor, one member is chosen by ODOT, and those two members choose the Chair of the Board. members.

The DRB conducts quarterly meetings and is provided monthly progress meeting minutes, project schedule updates, and any other information it requests to keep up-to-date on the progress of the project. The DRB may also conduct a hearing at the third step in the Dispute Resolution Board Process and provide recommendations to the Director of ODOT as to the disposition of that claim.

PN 108 sets forth the details of each of the three steps of the Dispute Resolution Board Process. These three steps include On-Site Determination, District Dispute Resolution Committee, and the Dispute Resolution Board. PN 108 sets forth specific submittal timeframes at each step which must be met by both the Contractor and ODOT personnel to move a dispute toward resolution.

The DRB may also be asked by mutual agreement of both parties to render an Advisory Opinion. An Advisory Opinion may be used to provide the parties with a preliminary assessment of the merits of each party’s position in a dispute based upon the information presented. The process is meant to be expedient, primarily oral, and will not prejudice a future formal DRB hearing of the dispute.

The expectations and responsibilities of the Contractor, ODOT and the DRB as well as the compensation of the DRB members are included in the Dispute Resolution Board Three Party Agreement. This contract is signed by ODOT, the Contractor, and all three DRB members prior to the first DRB quarterly meeting.

Payment

§  A Special Item, Lump Sum, and Dispute Resolution Board will be furnished in the Proposal to pay for the services of the DRB members.

§  Monthly, the Chair shall submit to the Contractor the billable time and travel expenses for each board member.

§  The Contractor will pay the DRB members’ invoices. The Contractor will then submit the paid invoices to the ODOT Project Engineer for reimbursement payment under the above referenced pay item.

§  Under the Special Item described above, the Contractor will be reimbursed 100 percent of the costs associated with the quarterly meetings. The Contractor and the Department will bear 50 percent of the costs associated with the development and issuance of Step 3 proceedings or advisory opinions.

§  The ODOT Project Engineer will review each paid invoice. All billable time is to be at the rates agreed to in the Third Party Agreement and travel expenses, if applicable, are to be in accordance with Ohio Office of Budget and Management’s Travel Policy. Any adjustments necessary should be made on the subsequent invoice.

Dispute Resolution Advisor (PN 109)

A Dispute Resolution Advisor (DRA) is used on select projects whose contract value is between $5 million and $20 million.  Proposal Note 109 (PN 109) provides that a Dispute Resolution Advisor (DRA) be established prior to the start of construction of a project and exists through the life of that project. A DRA is an individual with a minimum of 10 years’ experience in construction, contract administration, and dispute resolution techniques. The DRA is chosen based on the guidelines set forth in PN 109.

The DRA conducts quarterly meetings and is provided monthly progress meeting minutes, project schedule updates, and any other information it requests to keep up-to-date on the progress of the project. The DRA may also conduct a hearing at the third step in the Dispute Resolution Advisor Process and provide recommendations to the Director of ODOT as to the disposition of that claim.

PN 109 sets forth the details of each of the three steps of the Dispute Resolution Advisor Process. These three steps include: On-Site Determination, District Dispute Resolution Committee and the Dispute Resolution Advisor. PN 109 sets forth specific submittal timeframes at each step which must be met by both the Contractor and ODOT personnel to move a dispute toward resolution.

The DRA may also be asked by mutual agreement of both parties to render an Advisory Opinion.  An Advisory Opinion may be used to provide the parties with a preliminary assessment of the merits of each party’s position in a dispute based upon the information presented. The process is meant to be expedient, primarily oral, and will not prejudice a future formal DRA hearing of the dispute.

The expectations and responsibilities of the Contractor, ODOT, and the DRA as well as the compensation of the DRA are included in the Dispute Resolution Advisor Three Party Agreement. This contract is signed by ODOT, the Contractor, and the DRA prior to the first DRA quarterly meeting.

Payment

§  A Special Item, Lump Sum, and Dispute Resolution Advisor will be furnished in the Proposal to pay for the services of the DRA.

§  Monthly, the Chair shall submit to the Contractor the billable time and travel expenses for each board member.

§  The Contractor will pay the DRA’s invoices. The Contractor will then submit the paid invoices to the ODOT Project Engineer for reimbursement payment under the above referenced pay item.

§  Under the Special Item described above, the Contractor will be reimbursed 100 percent of the costs associated with the quarterly meetings.  The Contractor and the Department will bear 50 percent of the costs associated with the development and issuance of Step 3 proceedings or advisory opinions.

§  The ODOT Project Engineer will review each paid invoices. All billable time is to be at the rates agreed to in the Third Party Agreement and travel expenses, if applicable, are to be in accordance with Ohio Office of Budget and Management’s Travel Policy. Any adjustments necessary should be made on the subsequent invoice.

Documentation Requirements – PN 108 Dispute Resolution Board Process & PN 109 Dispute Resolution Advisor

1.        Check monthly invoice hours for accuracy and reasonableness.

2.        Invoiced hourly rates cannot exceed hourly rates set-up in Three Party Agreement.

3.        Invoiced travel expenses cannot exceed maximums established in Ohio Office of Budget and Management’s Travel Policy.

4.        Verify all totals are mathematically correct.

5.        Verify items paid at 50/50 percent ODOT/Contractor split are correct.

6.        Document monthly Contractor reimbursement total on CA-D-1B.

Post Construction Meeting (108.02.H)

Hold a Post-Construction Meeting prior to project finalization.  Invite the design agency or any stakeholders necessary for the success of the meeting.  Partnering shall be included as an agenda item.  Use the standard Post Construction Meeting Agenda/Minutes form (CA-G-4) to document the meeting.

Partnering Close-Out Survey (108.02.I)

At least one representative each from the Contractor and ODOT should complete a Partnering Close-Out Survey at the conclusion of the project.  Use the standard survey available online through the Division of Construction Management’s Partnering website. The standard survey title, “Partnering Close-Out Survey,” can be found at the following link:

http://www.surveymonkey.com/s/ODOT_Partnering_CloseOut_Survey

Progress Schedule (108.03.A)

The Contractor must submit a progress schedule, pursuant to C&MS 108.03. This schedule must show the Contractor's plan to carry out the work, the dates which the Contractor and subcontractor will start the critical work, including the procurement of materials and equipment, ordering special manufactured articles, working drawings, and the planned dates of critical project milestones.

A bar chart schedule is the default schedule required for all projects. More complex project may require the Contractor to use the Critical Path Method (CPM) progress schedule as specified by Proposal Note 107.

The progress schedule must be reviewed and accepted by the District Construction Administrator. The Project Engineer will review the schedule and forward his comments to the District Construction Administrator. The following items are to be used in determining an acceptable schedule:

·         All major items of work must be included in the schedule.

·         Completion of the entire project must follow contract requirements.

·         Duration of activities must be reasonable.

·         Sequence of operations must be logical.

·         Schedule must be arranged per plan phases if required.

·         Schedule must include special provisions in the contract, including completion dates.

·         Special material requirements of the plans must be included.

The progress schedule is the responsibility of the Contractor. If the schedule does not make sense or is illogical, the District must ask for clarification. A revision of the details in question is required prior to acceptance.

Reviewing and Accepting the Contractor's Schedule

·         Is the project identified?

·         Does the schedule graphically depict the work?

·         Is there sufficient detail to truly describe the work?

·         Are the sequences and activity durations reasonable?

·         Are critical deliveries shown?

·         Is there consideration for winter months?

·         Are special ODOT requirements from plan notes or special provisions accounted for?

·         Does the schedule fit within the duration allowed by contract?

·         Are there clear relationships shown between activities?

 The progress schedule is the main tool with which the owner can monitor the progress of the contract and determine at an instant the status of work. It is, therefore, very important that the Project Engineer accurately review the schedule before acceptance. Monitoring the progress schedule is very important in determining "fault" or responsibility for project delays. C&MS 108.06 allows the director to grant requests for an extension of time if the work was delayed. Guidelines for the review and acceptance of the bar chart schedule are specified in C&MS 108.03.  Guidelines for the review and acceptance of Critical Path Method Progress Schedules are specified in Proposal Note 107.

Schedule Updates

There are several tools for monitoring the status of a project. The main tool, as stated above, is the monitoring of the progress schedule. The progress schedule must be reviewed at regular intervals with the Contractor at the project level by the Engineer and at the following times:

·         The start of the project to detect if the Contractor began as scheduled.

·         Every two weeks on larger more complex projects, monthly on smaller less complex projects.

·         Following the completion of a major item of work.

·         Following the completion of a phase or sub-phase of work.

Before, during, and after any type of delay to determine whether or not the delay was owner caused, contractor caused, or concurrent.

Results of this review must be included in the daily diary. The diary entry must list the reasons the Contractor cannot proceed with certain portions of the work. Accuracy and details in the daily diary concerning delays will protect the Department against the successful prosecution of many claims.

Determination of a Time Extension (108.06)

The Department may grant a time extension for excusable delays. The Contractor must make a written request giving details which will justify the granting of the request for this extra time. Methods to analyze requests for time extensions are explained in detail in C&MS 108.06 and Standard Procedure listed below.

It is more important than ever that the Contractor submit the request for a time extension in the following time frame:

·         Requests for an extension of time due to weather or seasonal conditions shall be submitted in writing to the Engineer at the end of each month.

·         Requests for extensions other than for weather and seasonal conditions shall be submitted in writing to the Engineer within 30 days following the termination of the delay and prior to the expiration of the extended contract date.

Extensions of time are processed as change orders by the District.

Procedure to Analyze a Request for Time Extension

The following procedures are to be used in the preparation and approval of a time extension: 

Evaluation of a Contractor’s Request for Time Extension

The District shall evaluate and process all requests for postponement of an interim completion date or a contract completion date within 30 days of receipt of the Contractor’s written request.  Perform the evaluation consistent with contract progress schedule requirements for the project using appropriate analysis principles and techniques.  If the request is approved, immediately process a change order in accordance with this procedure and the Standard Procedure for Processing Change Orders.  If the request is denied, immediately notify the Contractor in accordance with Section III of this procedure. 

Processing of an Approved Contractor’s Request for Time Extension

Prepare a Regular Work Change Order to postpone an interim completion date or a contract completion date.  The “Explanation of Necessity” shall include one of the following statements:

1.     The Contractor experienced an excusable, non-compensable delay due to weather as determined in accordance with C&MS 108.06.C. The revised (interim/contract) completion date is ______________.

2.     The Contractor experienced an excusable, non-compensable delay due to (insert reason) as determined in accordance with C&MS 108.06.B. The revised (interim/contract) completion date is ______________.

3.     The Contractor experienced an excusable, compensable delay due to (insert reason) as determined in accordance with C&MS 108.06.D. The revised (interim/contract) completion date is ______________. The allowable delay costs will be calculated in accordance with C&MS 109.05.D and processed on a subsequent change order.

4.     The Contractor submitted and the Department has accepted an Early Completion Schedules in accordance with C&MS 108.02.B.  The revised contract completion date is ______________.

Attach to the change order copies of analysis and progress schedules with support documentation or other justification substantiating the duration of the revision to the interim/contract completion date.

Once the change order amending the interim/contract completion date has been approved, the District Construction Office shall enter the amendment into SiteManager.

Processing of a Denied Contractor’s Request for Time Extension

The following procedure shall be followed when a requested time extension is not granted:

The District will notify the Contractor in writing, stating reasons for denial.  In the event a recovery schedule is warranted, the District will request that the Contractor submit a detailed plan to finish that will show completion by the current contract completion date.      If the Contractor disagrees with the denial of its request for time extension, the Contractor may pursue a remedy through the Department’s Dispute Resolution and Administrative Claim Process.

Behind Schedule

In the event that a request for an extension of time is not justified by the District and/or the Contractor falls behind schedule due to their fault or lack of responsibility, the Contractor may need to submit a recovery schedule.

When the progress differs appreciably from the original schedule (more than 14 calendar days), a revised schedule must be requested by the Department. A letter from the District Construction Administrator to the Contractor must be written to request a revised schedule and reasons for the delays. Once a new schedule is submitted and the reasons for delay are given by the Contractor, the Engineer must review the daily diary to determine the accuracy of these delays. If delays are due to poor or inexperienced workmen, C&MS 108.05 allows for removal of unskilled workmen from the project. If the delays claimed are caused by the Contractor, the revised schedule must show finishing by the original completion date and the method for recovery must be included.

The methods of monitoring a progress schedule are as follows:

·         Percentage of completion by dollars paid to the Contractor.

·         Examination of actual start and finish dates of line items.

Judgment must be used when reviewing the progress schedule. It may be possible that the dollars paid to the Contractor do not truly reflect the progress on the project. These issues must be discussed with the Contractor. A good time to do this is usually during the progress meetings when all parties involved with the project are present.

Delays (108.06)

Delays may be associated with some of the claims listed above and may require careful analysis to determine who is responsible for the delay. It is important to keep the following principles in mind when evaluating a delay claim:

The Contractor must demonstrate that the delay was critical. It must be shown that the delay in question affected the overall project schedule and was a controlling operation with respect to project completion.

Excusable Delays (108.06.B) are those delays, which are unforeseeable, beyond the control of the Contractor. Excusable Delays may be either compensable or non-compensable.

Excusable/Compensable (108.06.D) these are delays caused by the owner.  Examples include lack of site access, late shop drawing approval, redesign, etc.

Excusable/Non Compensable (108.06.B) these are delays caused by third parties outside the Contractors' control. Examples include area wide labor disputes, floods, transportation industry delays, fire, vandalism, etc.

Non-Excusable (108.06.E) Non-Excusable delays are always non-compensable. These delays are caused by the Contractor or under his control. Examples are subcontractor delays, late mobilization, production takes longer than scheduled, equipment breakdowns etc.

Very often delays can occur from various sources at the same time. These are called Concurrent Delays (108.06.F). An ODOT caused compensable delay occurring at the same time as an excusable delay, which is non-compensable, should result in a time extension, but no recovery of costs. An ODOT caused delay occurring at the same time as a contractor caused delay should result in a time extension, but no recovery of costs. Both cases relieve the Contractor from liquidated damages for the time in question.

The Contractor is entitled to plan and pursue the work in order to finish ahead of the contract completion date (108.02.B.2). If ODOT delays the Contractor, the Contractor may be entitled to impact costs.

Duty to Mitigate Delays (108.06.A)

The Contractor and the Department must make a reasonable effort to mitigate damages resulting from a claim event, whether caused by the Department, Contractor, third party, or intervening event. Mitigation might include re-sequencing work activities, acceleration, continuing work through a planned shutdown period, etc. The Contractor may be entitled to recover the costs of mitigation. Prior to implementing a change of any kind, the Contractor and the Department must have agreed on the method of compensation and time responsibilities in writing.

Waiver of Liquidated Damages (108.07)

If the Contractor fails to complete the work by the contract completion date (original or revised), he must request permission of the Engineer to remain in control of the work. The Contractor must make this request in writing and may be required to provide a written plan for completion of the work. This requirement is described in Section 108.07 of the C&MS, which includes a table of liquidated damages.

Certain plan notes may require interim dates for phase completion and include special liquidated damages. Different methods of bidding may include special liquidated damages.

Since the advent of SiteManager, the computer now deducts liquidated damages automatically from the estimates until dates for completion are entered or the time extension/waiver is processed and entered into the system.

Procedure to Waive Liquidated Damages

This standard procedure allows a waiver of all or portions of liquidated damages that accrued after the work is substantially complete and the conditions in C&MS 108.07 apply.

1.        The District shall evaluate and process all requests for waiver of liquidated damages within 30 days of receipt of the Contractor’s written request.

2.        Prepare a Form C-122a for a waiver of liquidated damages.  The remarks section shall include the conditions in C&MS 108.07 that apply.      

3.        The District Construction Office shall enter the waiver into SiteManager.

4.        Provide the Contractor with a copy of the completed Form C-122a.

Documentation Requirements – Waiver of Liquidated Damages 

1.        Form C-122a Waiver of Liquidated Damages

Termination

The two types of project termination are as follows:

Termination for Convenience (108.09)

Termination by convenience is explained in Section 108.09 of the C&MS and allows the Department to terminate a contract at any time. Several projects involving huge plan errors have been terminated. This is done to give the Department time to revise the plans and to allow the project to be bid competitively, rather than perform all work on change orders on the existing project.

Termination by Default (108.08)

Termination by default is explained in Section 108.08 of the C&MS. The Director has the right to terminate the project for the following reasons:

·         Contractor abandons, fails, or refuses to complete work.

·         Improperly performing the work.

·         Has not commenced work in a reasonable time or does not make reasonable progress.

·         Contractor goes out of business or files bankruptcy.

Termination by default or cause is not an immediate event. This type of default requires a series of events to occur over a period of time, all of which must be documented by the Department. Progressive documentation must occur and extensive records must be kept to avoid any legal action against the Department.

109 Method of Measurement and Payment

This section is presented to provide information and guidelines for the proper method of measurement of completed items of work and the proper payment to the Contractor.

General

In the administration of construction projects, it is the policy of the Department to provide the Contractor with prompt payment for all completed and accepted work.  After an item of work is completed, but before payment is made, a determination must be made based on the quantities of the various items of work performed. This will be the basis for final settlement between the Contractor and the Department.  It is the responsibility of the Engineer to ensure this determination of quantities is performed.  Likewise, the Project Inspector is responsible for making the detailed inspections necessary to measure, document, and turn in for payment the determined quantities.

As promptly as everyone expects their paycheck, the Contractor is entitled to prompt and accurate payment for all completed and accepted items of work. As outlined in the Ohio Revised Code Sections 126.30 and 5525.19 and this manual, the Department has the obligation to pay for completed items of work promptly. This payment must be made to the Contractor within 30 days of the first estimate date after the completion of the work, except for additional quantities found during the finalization process.  Failure to meet the progressive payment time will result in interest being paid to the Contractor from monies deducted from the District's budget.  To ensure prompt payment, the measurement of quantities and the recording for payment must be performed on a daily basis as the items of work are completed.

Project personnel are responsible for preparing documentation to support payment for work performed by the Contractor by measurement of completed and accepted quantities of work. This documentation serves two important purposes:

It provides validation that the quantity for payment has been determined in accordance with contract requirements (contract proposal, plans, specifications) with the necessary measurements, calculations, weight, etc. This is further detailed under the next section entitled, “Method of Measurement.”

It also verifies that the work was done in close conformity (as defined in Section 101.03 of the C&MS) to the plans and specifications.

Details on project documentation can be found throughout in this manual.

This Manual is not intended to alter or replace the specifications, its purpose is to supplement the specifications and provide assistance to the project personnel in the interpretation of the specifications. As such, this manual is not part of the contract by which the Contractor bids the project. This manual does provide the recommended minimum documentation requirements and guidelines with respect to measurement of quantities and basis of payment.

Changes and Extra Work (109.05)

General

The purpose of this section is show how modifications are made to ODOT construction contracts by change order. We will discuss reasons for change orders, pricing, preparation and processing, and record keeping.

ODOT contracts are unit price contracts using estimated quantities of work. Simply by the nature of this type of contract, change orders will occur if for no other reason than to adjust estimated quantities to the quantities of work actually performed. Change orders amend the contract by adding or deleting work, making reimbursement for additional costs incurred, making material substitutions, changing specifications, etc.

The Director is empowered by Section 5525.14 of the Ohio Revised Code to amend contracts for highway improvements by change order. This authority has the following statutory limitations:

·         Any original bid item can be increased to the lesser of 5 percent of the total original contract amount or $100,000.00.

·         A new item of work can be added to a contract to a value of the lesser of 5 percent of the original contract value or $100,000.00.

Additions beyond these limitations must be approved by the State Controlling Board. However, the director can exceed these limits if there are circumstances that warrant the declaration of an emergency. These circumstances could include a threat to public safety, idled equipment costs, delay costs, etc.

Guidelines for preparation of change orders are given in:

·         C&MS Section 104.02, 109.03, and 109.04.

State law, ORC 5517.02, and Federal-aid regulations require the Department to contract for work with the lowest competent and responsible bidder after advertisement of the project letting.

ORC 5525.14 authorizes the Director to add Extra Work to a project without competitive bidding and to adjust contract quantities as necessary to complete the project as intended.  This authority is subject to competitive bidding and Controlling Board requirements.

Building construction change orders will continue to be controlled by the Office of the State Architect (part of DAS), the Ohio Board of Building Standards, and good practice in the building construction industry.

Authority for Allowing Changes and Extra Work

Ohio Revised Code 126.30, 127.16, 5517.02, 5525.11, 5525.14, and 5525.99.

Code of Federal Regulations 635.

Procedure for Processing Change Orders

General

Work added or modifications to the contract documents made by change order must be only those which are necessary and integral to the completion of the project as intended by the original plan.  Work that is not necessary to complete a project as originally intended shall not be added to a project by change order and shall be contracted through the Department’s competitive bidding process or the Director’s emergency contracting authority.  Convenience or lower costs are not valid reasons to avoid the competitive bidding requirements of State law.

Added work must be within the existing right-of-way, covered by the approved environmental document and waterway and miscellaneous permits, and within the project limits stated in the plans.  If necessary, the District Deputy Director shall acquire additional right-of-way and/or reevaluate and update the approved environmental document and permits.  If necessary, project limits shall be modified utilizing the forms contained in this procedure. 

Each District shall develop and implement a collaborative process whereby the Production, Planning, and Highway Management Departments and the Construction Office reach consensus on the need for a change order before it is recommended in SiteManager (TRNS.PORT SiteManagerTM).

The District Construction Offices shall determine the terms and conditions (e.g., scope of work, compensation, deduction, etc.) of change orders in accordance with this procedure, the C&MS, and the MOP. 

All change orders shall be processed expeditiously to ensure prompt payment in accordance with ORC 126.30. 

The District Construction Offices shall develop all documentation, with the exception of formal Controlling Board requests, required for the processing of change orders.

Each District Construction Office must subscribe to the Blue Book by:  Printed book, CD-ROM, or Internet access and verify all equipment rates submitted by the Contractor.

All change orders shall be entered in SiteManager (TRNS.PORT SiteManagerTM). 

1.        The terms, conditions, and justification for such change orders shall be fully documented in the “Explanation of Necessity” section of the change order.

2.        One applicable reason code(s) must be assigned to each change order. 

3.        If multiple line items require different reason codes then separate change orders must be processed for each reason code and associated line item(s).

4.        The OCA will maintain a list of change order reason code descriptions on its website.

The Deputy Director of the Division of Construction Management may instruct that a change order be prepared and approve such change order after consultation with the District and the Director.

Regular Work Change Order (RWCO)

A RWCO shall only be used for the following:

1.        Contract quantity adjustments:

a.        Increases and decreases of contract quantities to meet field conditions and design modifications as provided in C&MS Section 109.04 within the Contract Limits.

b.        Decreases in Extra Work quantities.

2.        Adjustments for contract specified payments or deductions:

a.        Adjustment of a contract price when the item is reduced by more than 25 percent as provided in C&MS Table 104.02-2.

b.        Price adjustments as specified in the Proposal.

c.        Price adjustments as specified in an individual pay item’s specifications, such as, but not limited to, price adjustments specified in C&MS Sections 401, 446, 448, and 451 or the Proposal.

d.        Compensation for eliminated items as provided in C&MS Section 104.02.E and 109.04.

3.        Changes in the contract documents or specifications.

4.        Changes in materials requirements as follows:

a.        Allow a substitute material because of an area-wide material shortage or the specified material is not available.

b.        Acceptance of a superior material at no additional cost to the project.

c.        Acceptance of undocumented material incorporated into the work and performing satisfactorily.

d.        Department ordered change in materials.

e.        Accept with a cost savings, non-specification material incorporated into the work that is performing satisfactorily according to the Acceptance of Non-Specification Material Supplement.

5.        Revise an interim completion date or a contract completion date.

a.        The change order shall be for zero dollars.

b.        For change orders postponing the interim/contract completion date the “Explanation of Necessity” shall include one of the following statements:

i.         The Department accepts the Contractor’s early completion schedule in accordance with C&MS 108.02.B.2.  The amended completion date is _____________.  (Reason Code 32)

ii.        The Contractor experienced an excusable, non-compensable delay due to (insert reason) as determined in accordance with C&MS 108.06.B.  The revised (interim/contract) completion date is ______________.  (Reason Code 33)

iii.      The Contractor experienced an excusable, non-compensable delay due to weather as determined in accordance with C&MS 108.06.C.  The revised (interim/contract) completion date is ______________.  (Reason Code 34)

iv.      The Contractor experienced an excusable, compensable delay due to (insert reason) as determined in accordance with C&MS 108.06.D.  The revised (interim/contract) completion date is ______________.  The allowable delay costs will be calculated in accordance with C&MS 109.05.D and processed on a subsequent change order.  (Reason Code 35)

c.        Attach to the change order copies of analysis and progress schedules with support documentation or other justification substantiating the duration of the revision to the interim/contract completion date.

6.        Implement non-performances that result from the acceptance of a Value Engineering Change Proposal (VECP).

7.        Other reasons as authorized by Administrative Rulings issued by the Division of Construction Management.

Extra Work Change Order (EWCO)

1.        An EWCO shall only be used for the following:

a.        Increase of contract quantities to meet field conditions and design modifications as provided in C&MS Section 109.04 and are only those quantities that are beyond the Contract Limits. 

b.        The addition of new items of work.

c.        Increase of quantities previously established by an EWCO.

d.        Project termination costs in accordance with C&MS Section 109.04 when the contract is terminated for convenience of the Department under C&MS Section 108.09.

e.        Force Account (commonly referred to as Time and Materials [T&M]) in accordance with C&MS Section 109.05.C and the Force Account Section of this procedure.

f.         Implement an accepted VECP according to the procedure on Value Engineering and payment of the Contractor’s share of the VECP savings.

g.        Payments that differ from fixed amounts established in the Proposal by the Department for specified items.

h.        Final payment for an item that differs from the lump sum amount bid by the Contractor.

i.         Payment for allowable delay costs.

j.         The payment of interest on delays in processing payments.  Interest will be calculated according to ORC 126.30.  In all cases, interest shall be a separately itemized payment utilizing the item code and description for interest that can be found on the Item Master.  Interest shall not be included as part of a negotiated price.

k.        Compensate the Contractor for damages associated with claims in accordance with recommendations issued by the Dispute Review Board in accordance with the Dispute Review Board Process, decisions issued by the Director’s Claims Board in accordance with the Dispute Resolution and Administrative Claims Process, and decisions rendered by the Ohio Court of Claims.

2.        The EWCO shall include a “Description of Work,” and when necessary, a “Supplemental Description.” 

a.        If the EWCO is for an increase in a contract quantity, use the existing “Description of Work” for that item.

b.        If the EWCO is for the addition of a new item of work, use a “Description of Work” contained in the Item Master. Use a “Supplemental Description” that clearly identifies the work for which the EWCO is being processed.

3.        The EWCO “Explanation of Necessity” section shall include, at a minimum, the following information, if applicable:

a.        A thorough discussion of all the agreed upon or imposed terms and conditions.

b.        Basis of compensation (e.g., negotiated prices [109.05.B] or force account [109.05.C]).

c.        For change orders that are for an increase in quantity for an original bid item include a reference to the RWCO that increased quantities to the Contract Limits.

d.        A statement indicating that the FHWA Transportation Engineer has been consulted.

e.        A statement regarding federal participation eligibility and the effect on federal project funding.

f.         Whether the work will require additional time.  Use one of the following statements:

i.         The additional work will not delay work on the critical path and will not delay the project.

ii.        The additional work will delay work on the critical path and will delay the project ____ days.  A change order postponing the contract completion date will be processed.

iii.      The additional work will delay work on the critical path, but will not delay the project.

iv.      At this time, it is unknown how the additional work will affect the work on the critical path and time to complete the project.  The contractor will perform and submit a schedule analysis within 30 days of the completion of the work authorized by this change order.  A subsequent change order revising contract time will be processed, if warranted.

g.        If the EWCO includes any work that is subject to price adjustments as specified in the Proposal.

h.        If any additional cost of maintaining traffic is included in the agreed prices.

i.         If any additional cost to revise or provide a Storm Water Pollution Prevention Plan is included in the agreed prices.

j.         The details of a contractor’s reservation of rights in accordance with the Execution and Distribution Section.

k.        If the change order is compensating the Contractor for damages associated with a claim, the description of the change order shall include a disclaimer stating: “The execution of this document constitutes full settlement of Dispute or Claim Number (  ) and all rights for any additional compensation based on this cause are waived.”

4.        All supporting documentation, including the complete cost analysis, shall be attached to the copy of the EWCO on file in the District.

Force Account

1.        An EWCO for the Estimated Cost of Force Account (ECFA) shall be processed if the amount of the force account work is likely to be greater than $100,000 and is expected to take more than two weeks to complete.  When the amount of the force account work is likely to be less than $100,000 and is expected to take less than two weeks to complete, an EWCO for the Actual Cost of Force Account (ACFA) can be processed without processing an associated ECFA.  

2.        Estimated Cost of Force Account (ECFA)

a.        All ECFA’s shall be paid by an EWCO.

b.        The ECFA shall state the estimated costs as determined by a cost analysis or estimate based on similar bid items according to the C&MS and MOP.

c.        An original affidavit by the Contractor shall be attached to the change order stating:

"Labor rates shown are the actual rates paid for labor, unit prices for materials and rates for owned and rented equipment have been estimated on the basis they are not in excess of those charged in the area in which the work will be performed."

d.        The District will process estimates on ECFA every two weeks as the force account work is performed.

e.        Approval of an ECFA change order allows payments as the work is performed up to the estimated change order amount. 

3.        Actual Cost of Force Account (ACFA)

a.        After the work covered by an ECFA is complete or if an ECFA is not necessary as described the above Section of this procedure, the District shall prepare an ACFA reflecting the actual total cost in accordance with the C&MS and MOP and substantiated by a summary of the actual cost of performing the force account work.

b.        The difference between the actual cost and the original estimated cost of the force account work shall be entered as a plus (positive), minus (negative), or zero, as the case may be, and labeled "Difference Between Actual Cost and Estimated Cost of Force Account Work, Authorized by Change Order Number xx."

i.         If the difference is positive, another EWCO must be used to authorize payment beyond the ECFA.

ii.        If the difference is negative, an RWCO shall be used to non-perform the unused balance of the ECFA.

iii.      If the difference is zero, an RWCO shall be used to document that the actual costs equaled those shown on the ECFA.

c.        The “Explanation of Necessity” shall include the reasons for the difference in cost and any conditions encountered that differ from those originally anticipated in order to substantiate final payment.

d.        An original affidavit by the Contractor shall be attached to the change order stating:

“The name, classification, total hours worked and rates paid each person listed on the Summary of Actual Cost are substantiated by actual records of persons employed on the force account work. All unit prices for materials and rates for owned and rented equipment listed on the Summary of Actual Costs are substantiated by actual records of materials and equipment actually used in performance of the force account work and the price of any owned equipment not previously agreed upon does not exceed prices charged for similar equipment in the area in which the work was performed.”

Federal Highway Administration (FHWA) Consultation and Concurrence

1.        On all Federal oversight projects [per 23CFR635.120(a)(b) &(c)]:

a.        Following authorization to proceed with a project, all major changes in the plans and contract provisions and all major extra work shall have formal approval by FHWA in advance of their effective dates (23 CFR635.120 [a]). 

b.        For non-major changes and for non-major work, formal FHWA approval is necessary, but such approval may be given retroactively (23CFR635.120[b]).

c.        All change orders amending contract time shall be submitted for approval by FHWA.  When possible, change orders for contract time resulting from contract changes or extra work should be submitted at the same time as the change order for said contract change or extra work for approval by FHWA (23CFR635.120[c]).

2.        The District shall consult with the appropriate FHWA Transportation Engineer when a major change is first contemplated on a full Federal oversight project.

a.        This consultation may be by e-mail or by telephone with a follow up e-mail. The results of this consultation shall be documented in the project file and in the change order, “Explanation of Necessity,” as indicated in Extra Work Change Order Section of this procedure.

b.        The e-mail shall have the Project Number, PID, and the County-Route-Section in the subject line and include adequate information to determine the nature and extent of the proposed change.

c.        The purpose of the consultation is to determine the eligibility of the change for Federal participation, the effect on Federal project funding, and to obtain approval to execute the change order under the terms and conditions agreed upon in this consultation.

3.        FHWA considers a change order to be a major change if it:

a.        Results in a project cost increase exceeding the lesser of $250,000 or five percent of the award amount. 

b.        Alters the planned access controls, highway operations (highway operational characteristics), or work limits.

c.        Results in new environmental impacts.

4.        FHWA does not participate in maintenance items or the purchase of surplus material.

5.        FHWA does not participate in the repair of completed permanent items of work damaged by traffic and compensated under C&MS Section 107.15 with the following exceptions:

a.        FHWA participation is allowed on federally funded projects off the NHS as determined by State law and policy.

b.        FHWA participation is allowed on federally funded projects on the NHS when the proximate cause of damage was the result of traffic being diverted from its normal path by construction activity.

6.        Copies or electronic versions presented through an ftp website or document management system of all change orders, including support documentation, shall be submitted to FHWA for approval on full federal oversight projects only.  (Final approval of all major and minor change orders by FHWA based on the change order documentation review is permitted following execution of the change order by ODOT subject to the provisions of this Section of the procedure.)

7.        ODOT approves change orders on behalf of FHWA for state administered federally funded projects.  Change order documents are retained by ODOT only on state administered federally funded projects.

8.        The Division of Construction Management will coordinate the review and advance approval of all claims on full Federal oversight projects with FHWA.

a.        The Division of Construction Management will provide notification to FHWA upon receipt of Notice of Intent to File a Claim.

b.        The Division of Construction Management will provide a copy of all claims decisions for review and advance approval prior to final execution of any change order that may result from the decision.

9.        Federal oversight project criteria are provided in the ODOT/FHWA Stewardship & Oversight agreement which can be found at: www.fhwa.dot.gov/ohdiv/soa.htm. 

10.     Any questions regarding the status of federal oversight projects can be directed to the FHWA Transportation Engineer assigned to your District.  The current FHWA Transportation Engineer map can be found at: www.fhwa.dot.gov/ohdiv/.

Program Manager Consultation and Concurrence

1.        District Program Manager.

a.        Change orders on district funded projects must be approved by the appropriate district program manager in accordance with processes established by the DDD.  

2.        Central Office Program Manager.

a.        Change orders on projects funded by a Central Office program must be approved by the Program Manager (PM) if the change order amount exceeds the specified threshold for the program.   Districts shall consult the appropriate PM when they first anticipate a change order over the threshold. The OCA will maintain a list of Program Managers and thresholds for each program on its website.

b.        The Deputy Director of the Division of Construction Management may require Districts on specific projects to consult with a PM on change orders below the normal program threshold.

Cooperation with Local Participating Agency (LPA) and Notice (ORC 5521.041)

Prior to approving any change order for an item containing local funding the District shall:

1.        Discuss with an agent of the LPA the circumstance giving rise to the change order.

2.        Provide written notice to the LPA detailing the proposed change order.

3.        Obtain written acknowledgement of the LPA’s receipt of notice of proposed change order.

Attach the written notice and written acknowledgement to the change order.  Except for Contract quantity adjustments less than Contract Limits, ensure that the change order is approved prior to performing the authorized work.  

Controlling Board (ORC 127.16 and 5525.14)         

An EWCO with a pay item in excess of the Contract Limits, regardless of the funding source, and not covered by the second paragraph below, must be submitted to the Controlling Board for approval prior to performance and payment of an EWCO.

1.        An EWCO shall NOT be divided into inappropriate pay items or participation codes for the purpose of avoiding Controlling Board review.

2.        Processing of Controlling Board Requests:

a.        The District shall recommend the EWCO, obtain the Program Manager’s signature, and obtain the Contractor’s signature in accordance with Execution and Distribution Section of this procedure. 

b.        The District shall forward to the Division of Construction Management the signed copy of the EWCO and a draft explanation appropriate for the Controlling Board request.  This draft explanation shall be free of technical jargon and shall give a person unfamiliar with the project a basic understanding of the project and the request.

c.        The Division of Construction Management will process the information submitted by the District and will officially request Controlling Board approval.

d.        The Division of Construction Management will notify the District by telephone or e-mail of the Controlling Board’s action by the next business day following the Controlling Board meeting.   The District shall then approve the EWCO in accordance with the Execution and Distribution Section of this procedure4.  DO NOT APPROVE THE EWCO UNTIL IT HAS BEEN APPROVED BY THE CONTROLLING BOARD.

e.        The District will then inform the Contractor of the Controlling Board approval.

f.         The Division of Construction Management will send to the District the executed Controlling Board approval of the EWCO.  This approval shall be attached to the EWCO on file.

An EWCO with a pay item in excess of Contract Limits, regardless of the funding source, must be reported to the Controlling Board quarterly in accordance with ORC 5525.14(B), but does not have to be approved by the Controlling Board as follows:

1.        An increase of a plan quantity that is determined during the final measurement of an item of work and which is coded as Final Measurements in SiteManager (TRNS.PORT SiteManagerTM).

2.        Added work necessitated by federally mandated requirements that did not exist at the time of the original contract award.

3.        Added work for which the Director has granted emergency permission to proceed with work in accordance with the Emergency Permission Section of this procedure. 

The Division of Construction Management will prepare and submit a Report to the Controlling Board.

Approval Authority

All change orders for the extension of an existing contract item of work or for the addition of a new item of work beyond the Contract Limits shall be approved by the Director.

All change orders for additional work (new work beyond the scope or elective work), which consists of multiple related items (existing or new), the sum of which exceeds the lesser of $100,000.00 or 25 percent of the original contract value, shall be approved by the Director. 

The District shall have authority to approve all change orders that do not require approval by the Director as set forth above.

For change orders requiring approval by the Director, the procedures are as follows:

1.        Change orders based upon an emergency declaration.

a.        The District Construction Office shall obtain declaration of emergency as set forth in the Emergency Permission Section of this procedure.

b.        The District Construction Office shall then prepare the change order and execute as set forth in Execution and Distribution Section of this procedure.

2.        Change orders based upon Final Measurement.

a.        The District Construction Office shall prepare and submit “request for Estimated final meaSuRement approval” or “request for Actual final meaSurEment approval” form to the Division of Construction Management for approval by the Director.

b.        The Division of Construction Management will obtain the Director’s approval and signature, promptly notify the District Construction Office of the Director’s action by e-mail, and return to them the fully executed document.

3.        Change orders not based upon an emergency declaration and not Final Measurement.

a.        The District Construction Office shall prepare and submit “request for preliminary change order approval” form to the Division of Construction Management for approval by the Director.

b.        The Division of Construction Management will obtain the Director’s approval and signature on “request for preliminary change order approval” form, promptly notify the District Construction Office of the Director’s action by e-mail and return to them the fully executed document.

c.        The District Construction Office shall then prepare the change order and execute as set forth in the Execution and Distribution Section of this procedure.

4.        The DCA shall have authority to recommend change orders requiring approval by the Director.

For change orders approved by the District, the procedures are as follows:

1.        The District shall establish a change order approval process whereby two different signatures are required. 

2.        The people selected to sign change orders shall be knowledgeable with this procedure and familiar with the project involved and the circumstances of the proposed change.  One signature on the change order shall be from a person within the Construction Department while the other signature shall be from a person not within the Construction Department.

3.        A person will be granted authority to recommend the change order.

4.        A person who is a Professional Engineer registered with the Ohio State Board of Registration for Professional Engineers and Surveyors will be granted approval authority.

5.        Several people may be authorized for each of the two signature levels on a project.

a.        The District shall inform the Contractor, at the preconstruction conference, of the people with change order approval authority for the project.

b.        The Deputy Director of the Division of Construction Management has approval authority of change orders prepared in accordance with the General Section of this procedure.

Execution and Distribution

In all cases, the District Construction Offices shall coordinate and obtain all necessary approvals (e.g., FHWA, Director, Program Managers, Controlling Board, Local Participating Agency) prior to execution.  Printed copies of change orders shall be signed, copies distributed, and filed as follows:

1.        A person with recommended authority signs and dates on the “Recommended by” line indicating their title as appropriate.  This person shall enter this action into SiteManager (TRNS.PORT SiteManagerTM).

2.        The District shall indicate any required Program Manager approval on the change order.  If approval is required, the District must indicate the date concurrence was obtained and provide documentation verifying concurrence.

3.        The Contractor signs and dates on the “By Contractor” line indicating their title as appropriate.  At the discretion of the District, contractor signature can occur before or after signature by the person recommending the change order.

a.        In the event a Contractor attempts to “reserve its rights” either on a separate document (e.g., cover letter) or on the face of the change order:

i.         The District shall not execute change orders which contain any sort of reservation of rights language included by the Contractor except as set forth below. 

ii.        Under limited circumstances, there may be a few instances where it is not feasible for the Contractor and Department to reach full agreement on all the costs and/or time damages arising from a specific circumstance.  However, these instances should be rare.  In such cases, it is expected that the Contractor notify the Engineer of its specific need and justification for such need to reserve its rights to claim specific time or costs at a later date.  The Engineer may, only with the approval of the Division of Construction Management, permit a Contractor to reserve its rights.  In all cases, when a reservation of rights is permitted, the details of the reservation of rights shall be documented in the “Explanation of Necessity” section of the change order.

iii.      Any additional time required to process the change order as a result of this decision will not be justification for interest.

4.        For change orders approved by the Director:

a.        The District Construction Office shall then submit the change order to the District Deputy Director

b.        The District Deputy Director will obtain the Director’s signature providing the approved preliminary amount of the change does not increase in value and the scope of the change remains consistent with the approved preliminary request.  In the event that an increase in the approved preliminary amount of the change order or a change in scope occurs, the District Construction Office shall submit a revised preliminary approval document to the Division of Construction Management for Director approval as set forth in the Approval Authority and Authority to Proceed Sections with work.

c.        The District Construction Office shall notify the Division of Construction Management of this approval action by e-mail with an attached copy of the fully executed document.

d.        A person assigned approval authority for District level change orders for the project shall enter this action into SiteManager (TRNS.PORT SiteManagerTM).

5.        For change orders approved by the District:

a.         A person with approval authority signs their own name as a Professional Engineer with the initials P.E. next to their signature on the “Approved by” line and enters the date.  This person shall enter this action into SiteManager (TRNS.PORT SiteManagerTM).

b.        Do not approve a RWCO that is for the increase in the quantity of an original bid item to the Contract Limits that is in companion with an EWCO for the further addition of quantities to that same original bid item until the Declaration of Emergency or other preliminary authorization for the EWCO has been granted by the Director.

6.        RWCO’s:

a.         District sends the original signed document of all RWCO’s, including attached documents to the Office of Accounting for filing with the original contract.

b.        A copy of the signed RWCO shall be kept in the District project file.

c.        Copies of the signed RWCO’s shall be distributed to the Contractor and Project Engineer on all projects.

d.        Copies of all executed RWCO’s, including back-up documentation shall be provided to the FHWA on federal oversight projects.

7.        EWCO’s:

a.        District sends the original signed document of all EWCO’s, including attached documents to the Office of Accounting for filing with the original contract.

b.        A copy of the signed EWCO shall be kept in the District project file.

c.        Copies of the signed EWCO’s shall be distributed to the Contractor and Project Engineer on all projects.

d.        Copies of all executed EWCO’s, including back-up documentation, shall be provided to the FHWA on federal oversight projects.

e.        Copies of signed EWCO’s, for additions due to Final Measurements and work added due to Federal mandates, shall be sent to the Division of Construction Management upon request for inclusion on the quarterly report to the Controlling Board.

Emergency Permission

Authority to proceed with work prior to processing a change order may be granted to the Contractor by the following people under the specified conditions and procedures.  The Director may grant emergency permission under ORC Section 5525.14 to proceed with added work that exceeds the Contract Limits prior to processing a change order.

1.        This permission shall be in writing and granted to add work  that is necessary to eliminate emergency circumstances that would:

a.        Create a life, safety, or health threatening situation.

b.        Unduly delay the completion of a project and increase its costs.

2.        Added work in these circumstances may include the following:

a.        Construction needed to complete a project.

b.        Adjustments needed to meet changed conditions.

c.        Alterations in original plans.

d.        Unforeseen contingencies.

e.        Payments necessitated by contract terminations or suspensions.

3.        The declaration of emergency and permission to proceed with work shall be fully documented using only the “DECLARATION OF EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form.

4.         The District Construction Office shall complete the “DECLARATION OF EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form, including all supporting documentation, obtain signature of the DDD, and submit to the Division of Construction Management for approval by the Director.

5.        The Division of Construction Management will obtain the Director’s approval and signature on “DECLARATION OF EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form, promptly notify the District Construction Office of the Director’s action by e-mail, and return to them the fully executed document.

6.        The original signed “DECLARATION OF EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form with supporting documentation shall be kept in the District project file.

7.        Copies of the signed “DECLARATION OF EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form shall be sent to:

a.        The Contractor, as the Department’s written commitment to pay for the work.  The Contractor may proceed with the proposed work; however, it is not legally required to perform the proposed work until the change order is approved,

b.        The Project Engineer.

8.        Attach a copy of the emergency permission to the subsequent EWCO.

9.        The EWCO shall be designated “Emergency” in SiteManager (TRNS.PORT SiteManagerTM).

10.     When the amount of an emergency change order exceeds the authorized amount, the Director may authorize the excess amount by an amended emergency declaration using only the “AMENDED EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form.  Copies of the “AMENDED EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form shall be distributed in the same manner as the original Emergency Declaration.

11.     When a District discovers that added work beyond the Contract Limits was performed without emergency permission, and the added work did not qualify as Final Measurements, the Director may declare an emergency provided the added work did qualify for emergency status.  This action must be documented on the “DECLARATION OF EMERGENCY AND PERMISSION TO PROCEED WITH WORK” form.

The DCA, under authority given to the Director by ORC Section 5525.14, may grant permission to proceed with new items of work, if the total payment for each pay item is less than the Contract Limits and Director authorization, if required, has been obtained.

1.        The written permission shall define the extent of the work and the agreed price for the work negotiated with the Contractor or the estimated cost of the force account.

2.        The District shall consult with the FHWA under the conditions stated in the FHWA Section of this procedure prior to granting permission to proceed.

3.        The District shall consult with the Program Manager under the conditions stated in Program Manager Consultation and Concurrence Section of this procedure prior to granting permission to proceed.

4.        The permission shall be kept in the project file with a copy to the Contractor.

Change Orders for Payment of Claims

When such payments exceed the Contract Limits, a Controlling Board request and approval are required before payment is made. Payments for damages associated with claims do not qualify as an emergency. 

Change Orders on Projects under Litigation

Change orders on projects under litigation shall be coordinated with the Office of Chief Legal Counsel prior to submitting to the Contractor for signature.  Monthly, the Office of Chief Legal Counsel will supply each District with a list of projects that have pending litigation.  For each listed project, the District shall inform the Office of Chief Legal Counsel, Court of Claims Section, of the following:

1.        Pending disputes on each listed project that could result in a change order.

2.        Change orders currently in process on each listed project.

3.        All change orders approved on each listed project.

Extension of Project Limits

The DDD may extend Project Limits on a project under contract for the purpose of adding work outside of the original project only to accomplish the following:

1.        Complete the project as intended by the original plan.

2.        Eliminate circumstances arising from the project that would create a life, safety, or health threatening situation.

The procedures are as follows:

1.        The extension of project limits shall be fully documented on the “EXTENSION OF PROJECT LIMITS” form. 

2.        The original signed “EXTENSION OF PROJECT LIMITS” form with supporting documentation shall be kept in the District project file.

3.        A copy of the signed “EXTENSION OF PROJECT LIMITS” form shall be sent to the Project Engineer.

Monitoring of Compliance

The Division of Construction Management will conduct routine Technical Process Reviews (TPR) to ensure District compliance with this policy and procedure. 

Districts found in non-compliance may have their change order approval authority revoked until conformity is ensured.

Documentation Requirements – Change Orders

1.        Request for preliminary change order approval and permission to proceed with work.

2.        Declaration of emergency and permission to proceed with work.

3.        Request for estimated Final Measurement approval.

4.        Request for actual Final Measurement approval.

5.        Amended request for preliminary change order approval and permission to proceed with work.

6.        Amended declaration of emergency and permission to proceed with work.

7.        Extension of Project Limits.

Reasons for Change

The necessity for a change orders to an ODOT construction contract may arise for many reasons. The most common causes for change orders are discussed below.  A complete list of ODOT’s reason codes for change orders is included at:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Admin/Change%20Orders/CO_REASON_CODES.htm

Changes in Quantities of Work

The quantities of work actually performed differ from the quantities originally estimated and established in the contract for the following reasons:

·         Final Measurements/calculations.

·         Quantity changes to meet field conditions.

·         Plan errors.

Differing Site Conditions

Existing field conditions differ from the plan to the extent that performance of additional or non-bid work is required for the following reasons:

·         Differing subsurface conditions.

·         Presence of any conditions not shown in the plan.

Changes in the Scope of Work

Changes to the project that are so far reaching that they can be considered outside the original intent of the work can be caused by:

·         Significant changes in the quantities of work.

·         Significant alteration of the work due to:

o    Sequence of construction.

o    Method of construction.

o    Materials.

Changes for the Convenience of the Owner

Changes in the work ordered by the owner to meet the needs of the owner. The following changes are typically not required for the proper construction of the project:

·         Addition of new work or deletion of work.

·         Acceleration.

·         Change in materials.

·         Suspension of work.

Actions by Others

Restriction, regulation, or delay imposed on the Contractor beyond the terms of the contract by an entity who is not a party to the contract can be caused by:

·         Utility companies.

·         Railroads.

·         Regulatory agencies.

·         Local governments.

Common Change Order Elements

Practically every change order will contain the following elements:

Face

·         Project identification: project number, county, route, section, federal number, federal acceptance type.

·         Change order identification: change order number, type of change order.

·         Work item information: reference number, participation code, item code, item description, units of measure.

·         Cost information: unit price/lump sum amount, reference total, addition/non-performance, change order total addition/non-performance.

Body

·         Reference number identification: reference number, extra work number participation code.

·         Reason code: mandatory field in SiteManager for each reference. SiteManager contains a list of reason codes to choose from.

·         Explanation of necessity.

Signatures

·         For request and approval by the Department.

·         For agreement by the Contractor.

·         For agreement by the local (when applicable).

Preliminary Approvals and Attachments (when applicable)

·         Emergency declaration, preliminary approval or Final Measurement request as approved by the Director.

·         Support documentation: additional information describing need for the change order.

·         Cost documentation: cost analyses, comparative pricing information, etc.

·         Forms and detailed instructions are available on the Division of Construction Management webpage.

Change Order Pricing

Once the need to perform extra work on a project has been identified a basis of payment for this work must be established. Pricing for extra work is usually established using one of the following methods.

Agreed Unit Price (109.05.B)

This method of pricing is used when the extra work can be broken down into measurable units. The number of units necessary to perform the work is estimated and a unit price is determined and agreed upon as described below. Final payment is based upon the final measurement of the number of units of work actually performed:

·         Unit prices already established in contract.

·         Comparative pricing. Contract unit prices for similar work on other projects (SiteManager database).

·         Use force account type analysis (Appendix V).

Agreed Lump Sum (109.05.B)

This method of pricing is a negotiated amount and can be used when the extra work can be identified as something that is usually paid as a "lump sum." The "Agreed Lump Sum" can also be used as an alternate to the force account method:

·         Prepare lump sum using force accounts style analysis.

·         Maintain force account record of the work for a period of time and use to develop lump sum.

·         Third party billing.

·         Lump sum adjustment.

Force Account (109.05.C)

A force account method is used when the work cannot be broken into measurable units or when a unit price cannot be agreed upon. This method reimburses the Contractor the actual costs of labor, equipment, and materials incurred in the performance of the work, including allowable overhead and markup. This method requires a significant amount of record keeping and is described in Section 109.05 of the C&MS.

This method usually requires the preparation of two change orders both of which use the same format. The first change order is known as an "Estimated Cost Force Account" and is established so that money can be encumbered and payments can be made to the Contractor as the work is performed. The second change order is known as an "Actual Cost Force Account" and represents the final accounting of the cost of the performance of the work and is used to reconcile the "Estimated Cost Force Account" change order.

Additional Contract Time for Extra Work

The performance of extra work or additional quantities of work may warrant an extension of contract time. Extensions of contract time may involve additional direct project overhead costs.

Record Keeping

Record keeping is an integral part of contract administration and is especially important when considering change orders. Adequate records must be maintained to document the need for changes and to establish pricing for extra work.

Quantity Measurements

Measurements of the quantities of work in the units prescribed by the plan actually performed by the Contractor must be recorded by the project personnel. Change orders must be prepared to make adjustments for any differences between contract quantities and the quantities actually performed.

Issues of efficiency or other similar factors may arise that may impact unit costs when the quantities actually performed differ significantly from those shown in the plan. For these occasions the quantity records must be thorough enough to determine actual production rates and other such items.

Force Account Work and Extra Work Using Force Account Style Analysis

The records required for force account pricing of extra work must accurately depict all labor, equipment, and materials used by the Contractor to perform the work. The items that are necessary to record are as shown below:

·         Description of work.

·         Contractor's work force

o    Employee name

o    Classification

o    Hours worked, regular and overtime

·         Contractor equipment

o    Type

o    Model

o    Age

o    Capacity

o    Hours worked

o    Hours idle

·         Materials

o    Description

o    Quantity

o    Invoices

Estimates (109.09)

General

The Department is required to pay for completed contract work promptly in accordance with ORC Section 5525.19, OAC Section 126.30, and C&MS 109.09. Interest penalty payments resulting from the tardy processing of progress estimates will be deducted from the appropriate District budget. Currently, it is the Department’s goal to pay the final estimate on the project within six months of the physical work complete date.

SiteManager will be used to generate progress estimates on the assigned estimate dates and to generate the final estimate when project finalization is complete.

It is the District Construction Administrator's responsibility to establish the first estimate date for a project. This first estimate date, in general, should be two weeks after the first day of work or as otherwise agreed to by the Contractor at the preconstruction meeting. Once the first estimate date is established, a second estimate date is established 15 days later. Estimates will continue to be generated on the same two dates per month as long as the project is under construction.

Authority for Payment of Estimates

 Ohio Revised Code (ORC) Sections 1311.25 - 1311.32, 5525.16, 5525.18, and 5525.19

Ohio Administrative Code (OAC) Section 126.30

PAYMENTS UNDER THE PROMPT PAYMENT ACT 2770.2A August 2, 1991

Daily Diary

The daily accumulation of the information entered on the project is found in CA-D-3 SM and/or CA-D-4 SM. When entered into SiteManager in the Daily Work Report, these forms will become the Daily Diary. The Daily Work Report has five tabs: DWR Info, Contractors, Contractor Equipment, Daily Staff, Work Items, and Force Account.

All information contained on the CA-D-3 SM/CA-D-4 SM forms is transferred by the project personnel to one of these tabs. For purposes of payment of completed items of work, pay items listed on the CA-D-3 SM/CA-D-4 SM forms are entered on the Work Items tab.

Once all information is entered on the various screens of the  Daily Work Report, the Engineer, or alternate who has update authority, reviews the report, and if found acceptable, approves it as the Daily Diary. This approval is performed on the Diary screen.

Once approval of the Daily Diary takes place, the SiteManager system automatically transfers any quantities turned in for payment to the Estimates screen. This SiteManager screen lists details about individual reference number quantities completed for payment. Any amount shown on this screen as being completed, but not previously paid, will now be picked up for payment when the next estimate is generated.

Procedure for Payment of Estimates

This procedure establishes uniform processes and criteria for the prompt payment of completed contract work on Ohio Department of Transportation (ODOT) administered projects. 

Estimates for Progress Payments

The District shall establish procedures for approving estimates and payments as required by C&MS Section 109.09. These procedures shall include the following minimum requirements:

1.     Establish the first estimate date at the Preconstruction Conference. The first estimate date should be two weeks after the first day of work or as otherwise agreed to by the Contractor.

2.     Obtain from the Contractor an executed Contractor Signature Authorization CA-D-10 Form at the Preconstruction Conference.

3.     Assign SiteManager approval authorities. 

4.     Confirm the accuracy of the pay quantities and delivered material quantities entered into SiteManager.

a.     Project inspectors may be granted update authority to enter these quantities.

b.     Delivered materials will be paid in accordance with C&MS Section 109.10 and ORC Section 5525.19.  Delivered material invoices shall be kept in the project file.

5.     Verify that all pay items have associated materials approved at the time of the estimate approval.

6.     Establish a process for the daily review of SiteManager to determine estimates requiring approval.

7.     Establish a process to override deficiencies on a SiteManager estimate. Deficiencies are limited to the following:

a.     An estimate held for deficient payrolls when the District verifies that all required payrolls were submitted, reviewed, and are acceptable.

b.     An estimate held for the lack of material approval when the PE/PS establishes that the material used is approved and the hold is caused by the approval not being processed in time for the estimates.

8.     Record the date the estimate was transmitted to Contractor for certification.

9.     Obtain from the Contractor an executed Contractor Progress Payment Certification CA-D-11 form.  Do not approve an estimate until it has been reviewed by the Contractor and the required certification received.  Every estimate must have a signed Contractor Progress Payment Certification CA-D-11 Form attached to the estimate and retained in the project records.          

Issue payment for contract bonds any time following the execution of the contract, but no later than two weeks after the start of work.

Payments withheld to satisfy liens against contract funds in accordance with ORC Sections 1311.25 - 1311.32 will be withheld by the Office of Accounting. 

Final Estimates and Processing Estimates after Physical Work Completed (PWC)

Following completion of physical work, agreements are reached with the Contractor as to final quantities. These agreed upon quantities are generated with the Final Quantities report from the SiteManager Portal. 

Calculate and enter final price adjustments as required by the Contract, such as bituminous price, fuel, steel, Portland cement concrete pavement or base thickness, smoothness, etc.

The District generates and approves the final change order. The District generates and approves the final estimate. The final estimate shall be from zero dollars ($0.00) to no more than five-hundred dollars ($500.00). 

The District Construction Administrator shall certify the correctness of the Final Estimate by signing it. Final quantities shall agree with the Contract quantities as adjusted by the approved change orders on the final report.

The District shall inform the Contractor by letter that the Final Estimate has been signed. Use the Final Estimate Letter standard form. Distribute copies to the Surety and others as indicated on the sample letter.

The District shall enter dates for appropriate finalization milestones on the Key Dates/Critical Dates screens in SiteManager.

Copies of the signed Final Estimate and signed Final Report with Summation of Extra Work Items shall be submitted to Central Office Capital Accounting as the Final Package. Distribute copies of the Final Package as follows:

1.        Non-Federal Projects - Submit one signed copy each of the Capital Final Estimate and one signed copy of the Contractor Final Estimate with the final report attached.

2.     Federal Projects - Submit one signed copy each of the Capital Final Estimate and two signed copies of the Contractor Final Estimate with the final report attached.

The Final Payment shall be generated by Central Office Capital Accounting when all the requirements of C&MS section 109.12 have been fulfilled and the FHWA final voucher is issued.

Administrative Closing

In the event the District cannot obtain all the required documentation and judges that the Contractor cannot supply these documents, the District will refer the project to the Division of Construction Management for an Administrative Closing.

The Administrative Closing referral will consist of:

1.     The signed final estimate copies, if available.

2.     The finalization documents that were received.

3.     Written explanation of why the Contractor cannot provide the required documents.

4.     Written explanation and documentation of the efforts the District has made to obtain these documents.

The Division of Construction Management will perform Technical Process Reviews (TPR’s) of the District project files to assure proper finalization of projects.

Documentation Requirements – Estimates

1.        CA-D-10: Contractor Signature Authorization.

2.        CA-D-11: Contractor Progress Payment Certification.

3.        CA-D-12: Contract Compliance Certification.

4.        Final Estimate Letter.

Project Approval of Estimates

The Engineer is responsible for the electronic approval of their project's estimate on each estimate day. Before this approval takes place at the project level, the Engineer must ensure that:

·         The pay quantities and delivered material quantities entered into SiteManager are correct.

·         Any liquidated damages due to failure to meet an interim completion date are entered into SiteManager.

·         Any pay item deficient in material approval and not eligible for override is deleted from the estimate.

·         An executed Contractor Progress Payment Certification CA-D-11 form is obtained from the Contractor.

With respect to delivered materials, payment is allowed in accordance with Section 109.07 of the C&MS and ORC Section 5525.19. Payment is limited to approved, durable items that have a significant value in comparison to the total price of the contract and shall not be in excess of what is required to do the contract work. The unit costs allowed are the invoiced material costs and any reasonable delivery charges less any contractor's discounts. The allowed unit cost shall not exceed the applicable contract unit price. Delivered material invoices shall be kept in the project file. Costs for stockpile materials may be established by documents other than invoices.

Payment for approved materials outside the vicinity of the project may be made if it is determined that it is not practicable to deliver the material to the project site. This should apply to only bulky material that represents approximately $5,000 or more for related items of work. For small projects, payment for materials less than $5,000 may be made at the discretion of the District Construction Administrator. These materials are intended to include, but not be limited to guardrail, fence, aggregates, structural steel, precast concrete, light/strain poles, etc. Materials that have established shelf life or are temperature susceptible shall be protected in accordance with the manufacturer's recommendations. Small warehouse items shall not be included. Certain additional requirements must also be met before payment of delivered material off the project takes place.

·         The storage site of the material must be approved and documented in writing. This can be performed by the project personnel or other ODOT individuals (in cases where it is more practical for other Districts or Central Office Plant Inspectors to perform the inspection and provide the documentation).

·         The material must meet the same level of approval at the storage site as that required of material at the project.

·         The existence of the stored material must be verified and documented provided that it is designated or reserved for the particular project. This can also be performed by personnel from another District or Central Office when warranted by the location of the material.

·         Payment for off-site storage of material must also be supported by invoices kept on file in the project records.

Liquidated damages due to the failure of the Contractor to meet the project completion date are automatically accounted for by SiteManager. The Engineer must, however, enter into SiteManager any liquidated damages as a result of failure to meet an interim completion date, such as a road closure limitation required by the plan notes. This is performed by entering the dates subject to liquidated damage and the amount per day into the Contractor Adjustments tab in SiteManager. Both automatic and manual Liquidated Damages are then saved for inclusion into the estimate total. SiteManager automatically checks to see if enough materials have been reported, approved, and entered into SiteManager to cover the amount paid at the time the estimate was generated. If a deficiency occurs, the project shall make every effort necessary to resolve the deficiency issues as soon as possible.  SiteManager automatically checks to see if prime contractor payrolls have been submitted in a timely manner.  When deficiencies occur the project will check with the District Prevailing Wage Coordinator and resolve any deficiencies as soon as possible.  Consult the SiteManager Construction Administration Business Rules for resolving the material or payroll deficiencies. Once the Engineer has determined all the above has been accomplished, electronic approval of the estimate at the project level can take place. This is accomplished in the Contractor Payments tab and Estimates tab in SiteManager.  The estimate is now ready for the District Level Approval.

District Office Approval of Estimates

District Level Approval is the responsibility of the DCA or back-up person. Before this level of approval takes place, all deficiencies should be resolved. .

The DCA or back-up person can now approve the estimate. This is accomplished in the Contractor Payments tab and Estimates tab in SiteManager.  The estimate is now automatically forwarded to the Office of Accounting in Central Office for further processing and payment to the prime contractor.

Method of Measurement

In determining the proper method of measurement for a particular item of work encountered on a project, several sources of information exist. Section 109.01 of the C&MS provides general information for the determination of various units of measurement. These include items measured by weight, those measured by cubic meter (cubic yard), and those measured by the liter (gallon). In addition, specific information can be found for every listed pay item with few exceptions. Every item number in the C&MS contains a unique section entitled, "Method of Measurement," which provides this specific information. For example:

605.08 Method of Measurement.  The Department will measure Unclassified Pipe Underdrains, Shallow Pipe Underdrains, Deep Pipe Underdrains, Base Pipe Underdrains Construction Underdrains, Rock Cut Underdrains, and Prefabricated Edge Underdrains by the number of feet (meters) completed and accepted in place, measured from end to end of each run.

The Department will measure Aggregate Drains by the number of feet (meters) completed and accepted in place, measured along the bottom of the trench.

The few exceptions includes Items 402, 403, 404, 412, 446, and 448. These are all asphalt concrete items with the method of measurement for all these items described under Section 401.21. Likewise, Section 641.12 provides the method of measurement for all the pavement stripping items (642, 643, 644, and 645). No specific section exists for Items 441, 499, 501, 502, 505, 506, 508, 510, and 623. These are all general specifications, items involving lump sum payment, or items not paid separately, but included in other items for payment.

For items of work not covered in the C&MS, other sources can be utilized to determine the proper method of measurement. Supplemental Specifications are individual documents which describe the construction and material specifications for items whose requirements are changing from year to year, are still in the development or experimental stage, or are used only occasionally. These can be identified by their 800 series number. Just like the C&MS, these Supplemental Specifications contain a unique section entitled, "Method of Measurement," which provides the specific information for measurement purposes.

Items listed as "Special," which have no item number, have specific information with respect to proper measurement. This is included in a section entitled, "Method of Measurement," and is incorporated in either the plan notes or listed in the specific proposal for the project.

Another possible source of information with respect to method of measurement is items listed "as per plan." Reference items with an "as per plan" designation have been modified in some way from what would normally be required by the Specifications, Proposal, Standard Drawings, etc. This modification will be found in a plan note within the contract plans. The project personnel must investigate these "as per plan" modifications to determine what has been changed with the item.

For those projects designed in metric units, specific information with respect to measurement can be found. Section 109.02 of the C&MS provides information with respect to metrification, along with a list of conversion factors for converting English to metric.

Basis of Payment

As per Section 109.03, "Scope of Payment" in the C&MS, payment to the Contractor for an item of work performed by the Contractor shall be full payment for furnishing all materials and performing all work under the contract in a complete and acceptable manner. The "Basis of Payment" for any item of work details that the unit bid price is full compensation for certain work and/or materials essential to that item. As such, this work and/or material will not be measured or paid for under any other pay item which may appear elsewhere in the plans or Specifications. Like "Method of Measurement" (with few exceptions), every item number in the C&MS contains a unique section entitled, "Basis of Payment," which provides specific information as to what is covered by the pay item. The following example is provided:

613.10 Basis of Payment.  The Department will pay for accepted quantities at the contract prices as follows:

Item         Unit                                 Description

613          Cubic Yard                      Low Strength Mortar Backfill
                   (Cubic Meter)

613          Cubic Yard                      Low Strength Mortar Backfill
                   (Cubic Meter)                  (Type ___)

The few exceptions include Items 441, 499, and 501. These are all general specifications dealing with asphalt concrete, concrete, and structures.

For items of work not covered in the C&MS, the same type sources exist. As with "Method of Measurement," item numbers in the 800 series are covered under Supplemental Specification.

Items listed as "Special" also have a unique section entitled, "Basis of Payment." These are found either in plan notes or the proposal.

"As per plan" modifications need to be investigated by the project personnel. These modifications could change the basis of payment of the particular item of work.

Partial and Final Acceptance (109.11 and 109.12)

The purpose of this section is to explain the process by which ODOT construction contracts are closed out. We will discuss final inspections, the completion of contract requirements, the determination of the final contract value, and the issuance of the final payment and release.

 Following the completion of the physical work of a project, a process to "closeout" the contract begins. This process ultimately leads to the final payment and release of the Contractor from further responsibility for the project. This process includes gaining acceptance of the project from all participating agencies, determining the final value of the contract, the completion of all remaining contract requirements, and the issuance of a final change order. It is the Department's goal that this process be completed within six months of the completion of the physical work for at least 90 percent of our projects.

Completion of Contract Requirements

Once the physical work is completed for a project there are a number of administrative contract requirements that must be completed before final payment can be issued. These requirements may differ from contract to contract and typically include the processing of various documents or the Contractor supplying certain information:

·         Payroll requirements completed.

·         Affidavit of Compliance.

·         Final Wage Affidavit (state projects only).

·         Profilometer Report.

·         Concrete Core Report.

The dates on which each of these contract requirements has been satisfied are entered and recorded in SiteManager.

Final Inspection (109.12.A)

The Ohio Department of Transportation (ODOT) will perform a Final Inspection of all completed construction projects. The Final Inspection is typically conducted by a team that is headed by the District Deputy Director's Appointee for Final Inspection. This team shall include representatives of all local participating agencies and FHWA, when applicable, ODOT maintenance personnel, the Engineer, and the Contractor. The team will determine the need for any corrective or additional work and prepare a "Punch List" for the project. In the case of any disagreements among the team, the District Deputy Director's Appointee is empowered with final authority. The Punch List is provided to the Contractor in writing along with a specified time frame or a specified date for completion of the prescribed work. Final inspection must follow the standard procedure below and generally must include the following items:

·         Resolution of Punch List: It is the responsibility of the Engineer to perform any necessary follow-up to ensure that the Contractor completes the Punch List work in a timely manner.

·         Obtain acceptance of project by all local agencies: Upon completion of all physical work, including Punch List work, the District Construction Office must obtain a letter of acceptance of the project from all local participating agencies.

·         Issuance of Report on Final Inspection: Following the completion of Punch List work, if any, the District Deputy Director's Appointee for Final Inspection issues the Report on Final Inspection, form C-85. This report represents an informal acceptance of the project.

Each District Deputy Director will designate a person as the Final Inspector for their District. The person designated as the Final Inspector will be a Professional Engineer, registered by the State of Ohio, in order to comply with 4733.17 ORC. The Final Inspector will not be the Project Engineer for the project under inspection or any other person who had daily responsibility for inspection of the work. Each District Deputy Director will designate a person meeting the same criteria as the Final Inspector, as the Back-up to the Final Inspector.

Acceptance of a project or portion of a project by the Final Inspector or Back-up and their signature on the required form C-85 will constitute acceptance by the Director.

The Division of Construction Management will foster consistent standards of Final Inspection among the various Districts by sponsoring periodic meetings of all Final Inspectors and Back-ups.  The Districts shall comply with the standard procedures for final inspection of construction projects established in standard procedure below.

For ODOT administered construction contracts, the Final Inspection is a contract event to start Warranty Maintenance Periods, to relieve the Contractor of maintenance responsibilities, and to transfer maintenance responsibilities to the appropriate ODOT District or Local Public Agency (LPA). The Final Inspection of ODOT projects acknowledges receipt of the Contractor certifications of compliance with Contract conditions and work performed in a reasonably close conformity with the contract documents and consistent standards of inspection and project administration among the various Districts.

The Final Inspector and Back-up will do Partial Inspections to accept a completed significant portion of the work when such acceptance serves the mutual interests of the Contractor and Department or to start a warranty period according to the relevant warranty specification.

The Ohio Department of Transportation will perform a Final Inspection of Local Let, LPA projects to ensure general conformity with the approved plans and scope of the project in compliance with federal aid requirements.

Authority for Performing Final Inspection

Ohio Revised Code 4733.17

Federal Aid Policy Guide 635.105

Procedure for Final Inspection

The District Deputy Director (DDD) is responsible for appointing personnel to perform the Final Inspections on Department and LPA projects. This inspection is performed by the Final Inspector as the authorized agent of the Director.

1.        Each DDD shall appoint a Final Inspector and a Back-up Final Inspector to perform Final and Partial Inspections of construction projects in their District.

a.        Each Final Inspector and Back-up Final Inspector shall be a Professional Engineer, registered in the State of Ohio according to 4733 ORC.

b.        The Final Inspector and Back-up Final Inspector must have construction experience commensurate with the work being inspected.

c.        The Final Inspector and Back-up Final Inspector must have an independent and objective view of the work. Accordingly, the P.E./P.S. shall not perform the Final Inspection.

2.        The names of each Final Inspector and Back-up Final Inspector shall be submitted to the Central Office, Division of Construction Management, who will maintain a list of Final Inspectors and will verify their qualifications.

Near the completion of the work, the P.E./P.S. shall create an Engineer’s Punch List, in writing, of items not yet completed or requiring correction. The Engineer’s Punch List must be provided to the Contractor and all items on the list must be complete before the Final Inspection.

The P.E./P.S. shall inform the Final Inspector of the end of work and the completion of the items on the Engineer’s Punch List. The Final Inspection will be performed within 10 business days of the Final Inspection Requested Date in accordance with C&MS Section 109.12.  The date the final inspection is requested is entered into SiteManager as the Final Inspection Requested Date when applicable.

1.        Final Inspection, as defined in C&MS 109.12:

a.        The P.E./P.S. is responsible for coordinating attendance for the Final Inspection. In addition to the Final Inspector, the following people should be given an opportunity to attend the Final Inspection:

i.         Contractor.

ii.        District Highway Management Administrator or County Manager, in accordance with the District’s organization preferences.

iii.      Any local government representative, in accordance with part VII of this procedure, if the project is LPA.

iv.      FHWA, in accordance with part VI of this procedure, if the project is subject to federal oversight.

v.        Other relevant personnel.

b.        The Final Inspector shall review the pertinent contract documents and shall physically inspect the project.

i.         District wide projects (e.g., pavement marking, guardrail, etc.) may be checked by randomly selecting sections rather than inspecting all affected routes.

ii.        Particular attention must be made to the following critical items:

(1)     Rideability - If the project involves new pavement, resurfacing, bridge replacement, or a bridge overlay, it must be checked to see if it meets the applicable contract surface tolerance requirements. If the surface tolerances do not meet the contract requirements, the project must not be accepted.

(2)     Drainage - The pavements, a random selection of underdrains, ditches, conduits, catch basins, and other items must have positive drainage and be free of obstructions.

(3)     Structures - Bridges must be checked for all items which constitute the completed structure, both above and below the deck.

(4)     Erosion Control - Roadside items must be checked to see that all erosion control items have been placed or established. The project’s post construction Best Management Practices must be checked to ensure they are installed and working properly.

(5)     Safety - Guardrail, end treatments, impact attenuators, lighting, pavement markings, signing, traffic signals, and other safety items must be in place, properly installed, and functioning.

(6)     Clean-up - The project is not acceptable if clean-up in accordance with 104.04 is not complete. All borrow and waste areas must be restored in accordance with 105.16.

iii.      The Final Inspector shall also pay particular attention to items that are, by experience, known to be problematic.

c.        Report of Final Inspection (Form C-85-Final).

i.         The Final Inspector shall complete Form C-85-Final to document the condition of the work inspected during the Final Inspection. 

(1)     The Final Inspection date on the C-85-Final shall be the date the Final Inspector performs the Final Inspection. This date is entered into SiteManager when applicable.

(2)     If there are no Punch List items, the Final Inspector will fill in the date that the physical work was completed on the C-85-Final. This date is entered into SiteManager when applicable.

(3)     The Remarks section of the C-85 shall list Final Inspection Punch List items found during the Final Inspection.

(4)     The Form C-85-Partial or Form C-85-Final shall list the dates of the beginning of the warranty periods by item and location in the Remarks section.

d.        The Final Inspection Punch List.

i.         The Final Inspection Punch List is a list written by the Final Inspector denoting deficiencies found during the Final Inspection.

ii.        There shall be only one Final Inspection Punch List on a project. Punch Lists created by local authorities or other Department personnel will have no standing unless they are included on the Final Inspection Punch List by the Final Inspector.

iii.      At the Final Inspection, the Final Inspector and Contractor shall agree to a duration or date for the completion of the Final Inspection Punch List. The Final Inspection Punch List shall state:

(1)     The detailed list of items and locations found deficient during the Final Inspection.

(2)     The duration or date established for completion of the Final Inspection Punch List (this is the “stipulated time” denoted in 109.12.B).

(3)     The statement: Failure of the Contractor to complete the Punch List items by the stipulated time will result in the assessment of fifty percent of liquidated damages in accordance with 108.07 for every day beyond the stipulated time the Punch List work remains incomplete and beyond the revised completion date.

iv.      The P.E./P.S. shall notify the Final Inspector, in writing, of the satisfactory completion of the Final Inspection Punch List.

e.        Report of Punch List completion.

i.         When the Contractor completes the Final Inspection Punch List to the satisfaction of the P.E./P.S., the Final Inspector will complete the Report of Punch List completion.

(1)     The date of Punch List completion shall be entered in SiteManager as the date of physical work completed date when applicable.

(2)     Copies of the signed Form C-85 and report of Punch List completion shall be sent to the Contractor and the maintaining agency.

ii.        Liquidated damages can be waived as per the requirements of 108.07 and 109.12.B. if the Contractor completes the Punch List work in the stipulated time.

f.         End of Contractor maintenance responsibility.

i.         When the Final Inspector completes the Final Inspection and finds the work substantially complete or  substantially complete with Punch List items, the Contractor’s maintenance responsibilities end on the day of the Final Inspection for the project, except for:

(1)     Maintenance related to unfinished Punch List items.

(2)     Defects in work that becomes known before the final estimate is paid.

(3)     Specific items on projects that specify a guarantee, support, establishment period, or warranty period in accordance with the applicable specification.

ii.        The District shall immediately inform the appropriate maintaining agency of the end of the Contractor’s maintenance responsibility for the project. This is particularly important when guardrail, stop signs, traffic signals, or other safety devices are part of the project.

iii.      The Final Inspection does not waive any available rights of the Department nor divest the Contractor of any responsibility for compliance with the contract.

iv.      If there is a project guarantee, operational support, or continued maintenance that specifies a period of establishment (e.g., traffic control equipment, grass, trees, shrubs, or vines), the Final Inspector will note this period on the C-85, but shall accept the project without regard to completion of the establishment period. The Project Engineer is responsible for the inspection at the end of specified establishment period.

2.        Partial Inspection, as defined by C&MS 109.11. A Partial Inspection will only be performed following a request by the Contractor.

a.        Report of Partial Inspection (Form C-85-Partial). 

i.         If the Final Inspector determines that the work for which Partial Inspection was made was acceptable, the Final Inspector shall complete a Form C-85-Partial to document the Partial Inspection. 

(1)     The Partial Inspection date on the C-85-Partial shall be the date the Final Inspector performs the Partial Inspection.

(2)     The Final Inspector will fill in the work completed date for the work for which Partial Inspection was made on the C-85-Partial. This date is entered into SiteManager when applicable.

(3)     The Remarks section of the C-85-Partial shall state if there were any warranty items accepted during the Partial Inspection and list the specific location and item.

ii.        If the Final Inspector determines that the work for which Partial Inspection was made was unacceptable, the Contractor’s request for partial acceptance is denied and a subsequent partial inspection will not be granted. 

b.        End of Contractor Maintenance Responsibility.

i.         When the Final Inspector completes the Partial Inspection, the Contractor is relieved of maintenance responsibilities for the items of work identified on the C-85-Partial, except for:

(1)     Defective work or damage caused by the Contractor as defined by 109.11.

(2)     Specific items on projects that specify a guarantee, operational support, establishment period, or warranty period in accordance with the applicable specification.

ii.        The Partial Inspection does not waive any available rights of the Department nor divest the Contractor of any responsibility for compliance with the contract.

c.        The District shall immediately inform the appropriate maintaining agency of the end of the Contractor’s maintenance responsibility for the items of work identified on the C-85-Partial. This is particularly important when guardrail, stop signs, traffic signals, or other safety devices are part of the Partial Inspection. 

3.        FHWA Notification.

a.        If a project is designated as a federal oversight project, the FHWA representative shall be notified of the date of the Partial or Final Inspection and invited to participate.

b.        If the project is exempt from federal oversight, FHWA shall be notified when the project has been accepted.

4.        For ODOT administered projects, the Final Inspector shall sign and distribute copies of the completed C-85-Partial and C-85-Final forms to:

a.        Office of Accounting.

b.        Office of Construction Administration.

c.        Office of Contracts.

d.        County Manager.

e.        Maintaining Agency.

f.         District Warranty Coordinator (if warranty items).

g.        FHWA (if federal oversight project).

h.        Contractor.

i.         District LPA Coordinator (for traditional LPA projects).

j.         Local Participating Agency (for traditional LPA projects).

5.        For non-traditional LPA projects, the LPA will notify the Construction Monitor of the established time and date for the Final Inspection once the project is finished and corrective work items identified by the LPA are complete. The Construction Monitor will coordinate with the DCA/Designee or other ODOT/FHWA representatives, as appropriate, for attendance at the Final Inspection “walk-through” with the LPA and complete a District Construction Inspection Report marked “Final Inspection.”  Final Inspection Punch List items identified shall be noted in the “Remarks/Exceptions” section of the District Construction Inspection Report and assurance of completion is the responsibility of the LPA.  The LPA will supply the remaining closeout documentation to the District who will then closeout the encumbrance.

Documentation Requirements – Final Inspection

1.        Form C-85 Report of Final Inspection.

2.        Form C-85 Report of Partial Inspection.

3.        Report of Punch List Completion.

4.        Sample Final Estimate Letter.

Determination of Final Contract Value (109.12.C)

A key element of the project closeout process is the determination of the final dollar value of the construction project. This is accomplished by determining the final number of units to be paid for each item of the contract and by processing all necessary change orders, including a final change order. 

In order to ensure timely closeout, it is strongly recommended that some of the activities, which will be discussed, be performed as work is completed on the project.

Prepare and Audit Final Contract Quantities

The Engineer is responsible for determining and preparing support documentation for the final quantity (final number of units) to be paid for every item of work contained in the construction contract. Ideally, this is accomplished progressively as the items are completed during the course of construction of the project. Once the physical work has been completed for the project, the Engineer submits all project records to the District Office for an audit. This audit is performed by the District Level Reviewer for the purpose of verifying the final quantities and ensuring that adequate documentation exists to support payment of those quantities. It is currently the Department's policy to audit a minimum of 25 percent of all projects awarded each calendar year. The District can audit additional projects at its discretion. Again, it is preferred for larger projects that the audit be performed progressively as items of work are completed and documented. The audit must be performed before a list of approved final quantities is prepared and is forwarded to the Contractor for concurrence. Once agreement with final quantities has been obtained, a change order is prepared to make any necessary adjustments between the final and original contract quantities. Any necessary pay estimates resulting from these change orders are initiated by the District Construction Office.

Material Certification

As discussed in earlier sections, all materials incorporated into construction projects must be approved for use. Once the work is completed for the project, an audit must be performed to ensure that sufficient quantities of material have been approved for each reported final quantity. As the final quantity audit is being performed and final quantities are approved, the quantities are reported to the District Engineer of Tests for the material audit. The District Engineer of Tests and staff review the project testing and acceptance records to ensure that sufficient materials are approved for the final quantity for every contract item. Material deficiencies are reported to the Engineer who is responsible for resolution of the deficiency. Once all material deficiencies are resolved, the District Engineer of Test generates the Letter of Certification of Materials for the project. This letter is signed by the District Engineer of Tests and the District Highway Management Administrator and is included in the final estimate package.

The project closeout process is modified as follows for projects constructed under the material acceptance process described above.

Under this policy, the Engineer prepares a material certification for the project and submits it along with the final contract quantities to the District for an audit. The final quantity documentation is audited by the District Level Review Team as described earlier. The District Engineer of Tests now only audits the Engineer’s material certification using project audit guidelines similar to those used by the District Level Review Team. Deficiencies identified by the District Engineer of Test's audit are reported to the Engineer who is responsible for their timely resolution.

The Highway Management Administrator approves the material certification, which is included in the final estimate package.

Issuance of Final Change Order

A final change order is required for every construction project. Change orders for all quantity adjustments, extra work, additional costs, price adjustment, or contract amendments must be processed prior to the issuance of the final change order. Approval of the final change order signifies that all necessary changes have been made to adjust the contract from the original bid condition to the final "as built" condition.

Final Payment (109.12.D)

Following the approval of the final change order, the final estimate is prepared and processed, and the Contractor is released from any further responsibility for the project in accordance with C&MS Section 109.12.

Preparation of Final Estimate Package

A final estimate package is prepared for the project and includes the following items:

·         Final estimate (reconciles payment to final quantities).

·         Letter of Certification of Materials.

·         Certification of Payroll Affidavit (100 percent State projects only).

·         Letter of Acceptance from Participating Agency.

·         Affidavit as to Non-Specified Materials (when applicable).

·         Receiving ticket for Salvaged Materials (when applicable).

·         Signed Contractor Certification Form CA-D-12.

The final report is certified by the District Construction Administrator and the District Deputy Director. The final estimate is approved by the District Deputy Director.

Release Contractor from Further Responsibility (109.12.E)

Once submitted, the final estimate package is audited and approved for payment. Following this approval, the District Construction Office generates a letter to the Contractor advising of the final value of the contract and of their release. This letter also serves as the Department's formal acceptance of the project.  

200 Earthwork

201 Clearing and Grubbing

General

The purpose of this section is to establish uniform practices for clearing, grubbing, scalping, and removing trees and stumps within the areas designated in the plans.

The following terms are defined for clarity:

§  “Clearing” is cutting down all of the trees and brush.

§  “Grubbing” is clearing by digging up roots and stumps.

§  “Scalping” is removing the remaining roots, sod, grass, agriculture crop, sawdust, and other vegetation so that the soil is completely exposed.  This does not include removing topsoil.

Varying interpretations as to the extent of removal are possible where these removals are set up on a lump sum basis.  It is necessary to exercise judgment in the administration of this item to accomplish the desired results.

It is Department practice to remove only those trees that must be removed for the construction and maintenance of the highway and for the safety of the traveling public.  In certain circumstances, it is desirable to leave healthy trees in place.

Ohio Administrative Code regulates the movement of trees and wood in order to retard and prevent the spread of some destructive insects.  At present, the insects include emerald ash borer and Asian longhorned beetle.  The handling and transportation restrictions are listed on the website for the Ohio Department of Agriculture (www.agri.ohio.gov).

Disposal of Materials

All material disposals in the 200-series of C&MS refer to Sections 105.16 and 105.17.  The following statement is in 201.01 and is repeated throughout the 200s:

“Use removed or excavated materials in the work when the material conforms to the specifications; if not then recycle, burn, or dispose of the material according to 105.16 and 105.17.”

This statement is meant to encourage the Contractor to reuse, in the work, any material that can be reused. In the clearing and grubbing work, this is typically soil and topsoil.  Any material that can’t be reused needs to be disposed of properly.  The use, reuse, and/or disposal of these materials may be regulated. (See Section 105.16, Borrow and Waste, of this manual).

Plan Notes

There are three plan notes that may be used by the Department to determine the extent of the clearing and grubbing work on the project. These notes are described below and in the Location & Design Manual, Volume 3, Appendix B.  In every case, the plan will denote the limits of the clearing and grubbing.

Plan Note G109A

When Plan Note G109A is used, no trees will be specifically called out for removal. Everything is removed within the areas denoted in the plan.  In this case, the Contractor has the maximum risk if his field count is not accurate.  This note is often used on small projects.

Plan Note G109B

When Plan Note G109B is used, trees and stumps are marked for removal on the plan. This note is used where the designer can reasonably count all of the trees within the work limits.  This count should be accurate at the time of the count.

The count is not necessarily correct at the time of construction.  The Contractors are responsible to visit the site prior to the bid. This allows the Contractor to take tree growth into account.  Typical increase in growth is approximately 25 percent.  This depends on the time between the count and construction.

The Contractor should bring large discrepancies between the plan count and the actual conditions to the Department’s attention prior to the bid.

Plan Note G109C

When Plan Note G109C is used, everything in the plan limits is removed except for the trees denoted as “Do Not Disturb.”

The plan denotes some trees and stumps, where feasible.  In other locations, the plan denotes heavy wooded areas. An estimated count is given in the heavy wooded section.  This estimate is based on representative counts in the heavy wooded areas. 

There are inherent inaccuracies in this count.  The Contractor will be able to make an informed decision in his bid by the knowledge of how the count is made.  By denoting the type and accuracy of the tree counting, it minimizes the claims and change orders from this item of work.

Markings for trees to remain in place should be temporary and not result in an undesirable appearance beyond the life of the Contract. 

Trees Located within the Plan Limits Allowed to Remain

Trees that are located within the plan clearing and grubbing limits technically must be removed.  There are circumstances, however, where the Engineer may consider leaving trees in place or making other changes to the Contract.

It may be desirable to leave some trees because they are aesthetically pleasing and can provide structural value to an embankment or slope.  Leaving flowering trees and shrubs such as dogwood, redbud, hawthorn, and other attractive growth should be given serious consideration.  Special consideration should be given to rest areas or other specific nature locations.

The Project Engineer will contact the District Environmental Coordinator for recommendations on the attractiveness of trees to remain in place.

Where trees are allowed to remain in place, the area surrounding the trees should be cleared of undesirable undergrowth to provide an attractive appearance and to simplify maintenance.

Trees located within the plan work limits but outside the clear zone may not require removal.   It is required to remove trees within the clear zone or a minimum distance of about 30 to 40 feet (9 to 12 meters) from the edge of the travel lanes.  The actual clear zone distance depends on the roadway type.  The Project Engineer needs to contact the District Office of Production to give approval recommendations on the clear zone.

It is not necessary to remove trees beyond areas required for construction if the grading section is in a cut with a 3:1 back slope, or is in fill with a depth requiring a guardrail.

All trees considered for remaining in place must be in good condition.  A tree should be removed if it is dead, fallen, or unhealthy.

It may be necessary to remove some trees for fence or noise wall construction.  This type of removal must be within the right-of-way limits and should not be greater than 10 feet (3 meters) in width in dense growth.  Where trees are scattered, the removal should be confined to trees that are in line with the fence or noise wall.

The appearance of a mechanical cutting swath should be avoided when trees are left.  This can be accomplished by having a curved or irregular tree line defining the area rather than a straight-line effect.

Scalping (201.04)

It is essential that the project enforce scalping work when it is required.

Scalping is not required under an embankment where the embankment height is greater than 9 feet (3 m) to the subgrade elevation and when the existing slope is 8:1 or flatter.  Both conditions must be true for the location not to be scalped.  See Figure 201.04.1 for an illustration.

This requirement is in the specifications to ensure good friction between the existing foundation and the new embankment.  This construction technique minimizes future potential sliding.

Figure 201.A – Scalping Requirements

Documentation Requirements - 201 Clearing and Grubbing

1.        Proper Disposal (see 105.16 and 105.17).

2.        Mark Right-of-Way or cutting limits.

3.        Check the field conditions for accuracy.

4.        Count Trees or Stumps, if these are set up for individual payment.

5.        Check material removals according to 201.03.

6.        Check the required scalping locations.

a.        Use 201.04 for embankment foundations.

b.        Use 203.05 for benching areas.

7.        Measure and pay according to 201.05 and 201.06.

8.        Document on form CA-D-3A or CA-D-3B.

202 Removal of Structures and Obstructions

Structures Removed (202.03)

The plans will include a note regarding the bridge removal. The note will usually include the phasing of the demolition procedure, the requirement of the demolition plan, the specification of the equipment to be used, and the necessary protection for water ways and traffic.

Before the demolition starts, the Contractor should obtain an approval of the demolition plan, and notify the owners off all existing utility conduits using the structure.  The Contractor should disconnect all utilities according to local requirements.  If the Contractor is going to blast, then refer to 107.09 for the requirements associated with blasting.

Remove the substructures of existing structures, including piling, down to the proposed stream bottom.  For those parts outside the stream, and for bridges that do not span over streams, remove substructures to a minimum of 1 foot (0.3 m) below proposed ground surface.

Where the plans call for the removal of portions of the structure, remove those portions with sufficient care.  Avoid damage to the remaining portion of the structure.  In case of damage to the existing structure, repair or replace the damaged portions of the structure at no expense to the Department.

The contractor should remove asphalt wearing courses from the bridge before demolishing the bridge or portion of the bridge.  To this end, the Department pays for removing an asphalt wearing course separately from the structure removal.  This is to ensure that no asphalt ends up in a stream.  Even for bridges not over streams, the concrete deck may sometimes be broken up and used for erosion protection.  Therefore, the Department removes the asphalt from all bridge decks before demolition.

Backfill the cavity created by the removal item according to 503.09, except when the cavity lies within the limits of subsequent excavation or other work.

Asbestos on Bridges

The plans will include a note regarding asbestos on bridges. Contact the District Environmental Coordinator (DEC) to check for changes in the current law regarding Asbestos removal.  For a typical plan note, see the section, Typical Regulated Waste Plan Notes, Asbestos Abatement.  This note is similar but not the same as 202 Asbestos Pipe Removal specification requirements in Item 202.

The Contractor should adhere to plan notes and specification while conducting the removal.

If the existing conduit attached to the structure is not specifically denoted in the Contract Documents as Item 202 Asbestos Pipe Removed, perform the work according to 109.05 (Extra Work).

Pipe Removal (202.04)

When a pipe is removed from beneath existing pavement, there should be a separate pay item for removing the pavement.  If the pavement will be replaced, there should also be a separate pay item for the new pavement.  The pay item for pipe removal does not include the pavement, but it does include the excavation and backfill.

Asbestos Pipes

If removing an existing concrete water line pipe that was constructed before 1980, it may be an asbestos pipe.  Test the pipe by using a Department prequalified environmental consultant to determine if it is an asbestos pipe.  If it is determined that the pipe is asbestos, then a certified Asbestos Contractor must perform the removal. Dispose of all asbestos pipes at a solid waste facility that is licensed by the Local Health Department and permitted by the OEPA.  Contact the District Environmental Coordinator (DEC) to check changes in the current law regarding Asbestos removal.

If the existing conduit attached to the structure is not specifically denoted in the contract documents as Item 202 Asbestos Pipe Removed, perform the work according to 109.05 (Extra Work).

Asbestos is not a hazardous waste or a solid waste; it is a special waste.  This pipe is regulated and must be removed and disposed of properly.  .

When evaluating the potential for asbestos in the pipe, the project should look at the "Markings" on the pipe.  Concrete underdrain, waterline, and sanitary sewer pipe with the following “Markings” are known to contain asbestos:

§  ASTM C-663

§  AASHTO M-217

§  AWWA-C-400-64-T

§  ASTM-C-296-65-T

Individual utility companies and Local Planning Associations (LPA's) may have used asbestos pipe under their own specifications.

Asbestos Cement Perforated Underdrain Pipe was allowed in 706.15 in the 1970's.  In addition, Asbestos Bonded Bituminous Corrugated Steel Pipe and Pipe Arches were allowed in the 1980’s in 707.09.

Testing for Asbestos

Test the pipe for asbestos if there is any doubt about the pipe’s composition or identity. 

Asbestos inspectors in Ohio are required to have a certificate of training from an EPA accredited company for Asbestos Building Inspector and Asbestos Management Planner.  The certificates are sent to the Ohio Department of Health (ODH) to obtain the required Asbestos Hazard Evaluation license.  Both the EPA accredited certificate and the ODH license are required to perform inspections.

Asbestos Contractor Qualifications

There are a multitude of rules, laws, and regulations that govern asbestos operations.  One of the best websites is:

http://www.ehso.com/Asbestos/asbestreg.php

In addition, more information can be found under the Ohio Revised Code or the Ohio Administrative Code OAC-3701-34 and OAC-3745-20 at the following websites:

http://codes.ohio.gov/orc        

http://codes.ohio.gov/oac/3701-34

http://codes.ohio.gov/oac/3745-20

Asbestos Removal Contractors must obtain the Asbestos Hazard Abatement Specialist license or Asbestos Worker license from Ohio Department of Health (ODH). Each asbestos removal company needs to have an Abatement Contractor license through ODH as well.

The training requirements are under CFR 1926.1101(9) (i-viii) requirements for the truck drivers to haul the asbestos. The only training required for the truckers to haul the asbestos is two hour OSHA Awareness training.

Asbestos Pipe Removal

It is highly recommended that the Project hire a third party Certified Asbestos Inspector to provide oversight during the removal.

Concrete pipe is non-friable asbestos.  The pipe becomes friable if it is chipped, crumbles, or crushed during the removal.  Therefore, the same requirements are required for friable and non-friable asbestos pipe.  Cutting and crushing the asbestos pipe is strictly forbidden.  Follow the instructions of the Asbestos Inspector or Contractor.

The project may need to notify the local air quality authority and follow strict OSHA demolition and removal requirements.

The material must be taken to a solid waste facility that is licensed by the Local Health Department. 

Manifesting for disposal is required.  The Regulated Waste Project Engineer or the District Environmental Coordinator is required to sign the Manifest for the Department. See Appendix 202 Regulated Waste Requirements, “Manifesting” for more information.

Pavement, Walks, Curbs, Steps, Gutters, or Traffic Dividers Removed (202.05)

The plans will designate the items for removal using a balloon with (R for Removal) attached to a line pointing out the removal item. As designated, remove and dispose of the existing Item.  If removing only a portion of an existing item, saw cut a neat joint at the removal limit.

If the removed pavement will be replaced with embankment material, such as when an existing embankment is being raised, the Department pays for the embankment material separately. The embankment material is not incidental to the pavement removed.

Buildings Demolished (202.06)

The Contractor should disconnect all utilities according to local requirements, and notify the owners of water, electric, or gas meters when the meters are ready for removal. 

The Contractor should not disturb buildings until the Engineer provides a Notice of Possession and Approval to Proceed.  The demolition should be performed under the Engineer’s direction in order to accommodate utility rearrangements and clearance of structures.

The Contractor may use buildings for storage or other purposes.  The Engineer should secure a documented agreement to allow such use during the period of the Contract and save the Department harmless from any claims whatsoever by reason of such use.

Raze the building (including all items) to a minimum of 1 foot (0.3 m) below the grade of the surrounding area.

If the building contains any hazardous materials that require remedy before the start of the demolition, perform the necessary work under other items in the Contract or according to 109.05.

 Asbestos in Buildings

All structures torn down by the Department are required to have an Asbestos Inspection.  Ensure that the Office of Real Estate performed these asbestos inspections.  An Ohio EPA form, Notification for Asbestos Demolition and Renovation, must be filled out by the Department or the Contractor ten days prior to the Demolition. 

This form details the type and quantity of asbestos removed and small amount of asbestos left in the building.  Generally, the Asbestos Abatement Contractor performs all of the asbestos removal.  In rare cases, the asbestos abatement is performed under the highway contract.

The instructions and more details can be found at the following link:    

http://www.epa.ohio.gov/dapc/atu/asbestos.aspx

Normally, friable asbestos cannot be left in the building during demolition.  In rare cases, the Asbestos Abatement Contractor may leave a small amount of asbestos in the structure. Of course, large amounts of asbestos cannot be crushed or rendered friable.  If the amount of asbestos is small and the Notification for Asbestos Demolition and Renovation allows the building to be demolished, then this material can be hauled away to a Construction and Demolition Land Fill if allowed by the local Board of Health.

If asbestos is left in the building, the building cannot be burned, even if the Notification for Asbestos Demolition and Renovation allows the building to be burnt. 

The Notice will specifically mark on the form that the building can be burnt.  In addition, an Open Burning Permit would be required if the structure is burned. 

Burning or disposing of the building is allowed in 105.16 and 105.17.  The Contract will specifically state whether burning is restricted due to the asbestos left in the building.  This restriction will be based on the asbestos remaining in the building, and not on the Ohio Administrative Code (OAC) 3745 in 105.17. 

Contact the Office of Real Estate, Regulated Waste Project Engineer or District Environmental Coordinator for a clear recommendation on the disposal.

Underground Storage Tanks Removed (202.08)

The Department evaluates all project sites during the planning process to determine if Underground Storage Tanks (UST) are present on the project.  Typically the plans identify the tank location and requirements for removing or avoiding the UST in the work.  UST’s that were not identified in the planning process will be handled in the same manner as described below.

If an unidentified UST is encountered, take precautions to prevent a release of the tank contents to the environment.  The Project Engineer should notify the Regulated Waste Project Engineer, District Environmental Coordinator, or District Construction Administrator.  In the event of a tank release or safety related issue, contact the local fire authority immediately.  

Prior initiation of the underground storage tank removal, empty the tanks and dispose of the contents in conformance with all applicable regulations (OEPA and/or BUSTR).

Obtain the required permit prior the start of the UST removal.  Provide a State Certified BUSTR inspector employed by BUSTR, Delegated Authority (local fire department), or independent Certified Underground Storage Tank Inspector (CUSTI) contractor to perform the BUSTR required inspections.  Remove and dispose of the tank and its contents according to the Bureau of Underground Storage Tank Regulations of the Division of Fire Marshal (BUSTR), Ohio EPA, and all applicable federal, state, and local regulations.  Provide a Certified Tank Installer to supervise the removal.  For tanks containing hazardous substances other than petroleum, use and comply with the Ohio EPA regulations in addition to State Fire Marshal regulations. 

Testing is required for any excavated material and related water prior to disposal.  Perform the work under other items in the Contract or according to 109.05.  In addition to the required disposal sampling, conduct the closure testing in accordance with all applicable BUSTR regulations and prepare the BUSTR Closure Report.

BUSTR Requirements 

The State Fire Marshal and OEPA generally follow BUSTR regulations.  The State Fire Marshal’s Office, Bureau of Underground Storage Tank Regulations (BUSTR), controls the vast majority of the installations, uses, and removals of underground storage tanks in Ohio. 

See the BUSTR website for more information.  Valuable information can be found by looking up ‘download’ documents.  Additional information can be found by looking at the fact sheets at the following website:

http://www.com.ohio.gov/fire/bustmain.aspx

Project personnel must review the website and this section of the manual to become familiar with UST removal. 

The types of tanks regulated by BUSTR are detailed on the frequently asked questions page under, “What does BUSTR Regulate.”  

Specification and BUSTR Requirements

1.        A Certified Installer is required for any removal of a UST regulated by BUSTR. The Certified Installers are required to have photo identification.  The project engineer should check for this identification.  There is a list of the Certified Tank Installers on the BUSTR website. 

2.        A Certified Inspector is required to inspect the work.  This inspector may be a State Certified BUSTR inspector employed by BUSTR, Delegated Authority (local fire department), or independent Certified Underground Storage Tank Inspector (CUSTI) contractor.  The Contractor must supply this person as part of the bid work.  There is a list of these inspectors on the BUSTR website.

3.        A tank removal permit must be applied for 30 days prior to the work.  The Project Engineer should obtain a copy for project records.  The delegated authority (local fire department) or BUSTR may issue the permit. See the Fact Sheet entitled, “The BUSTR Permit Process.”  A copy of a permit application is on the BUSTR website.

4.        Even though the permit may be issued by the local fire department, BUSTR must receive a copy of the permit application 30 days prior to the removal.

5.        Tank registration may be required if the tank is not registered.  See the Fact Sheet entitled, “Underground Storage Tank Registration.”  In many cases the Department is the owner; the District Environmental Coordinator will handle tank registrations.  The registration form is on the BUSTR website.

a.        For unidentified tanks, the owners are typically unknown. Make certain that the registration and tank removal permit forms accurately identify the owner as “UNKNOWN.”  Never identify ODOT as the owner.

b.        If a tank was last used prior to 11/8/84 then ownership is the last person who used the tank, which may not be known.  In this case, make certain that the registration and tank removal permit forms accurately identify the owner as “UNKNOWN.” Never identify ODOT as the owner.

6.        The actual removal is summarized in the BUSTR Technical Guidance Manual. The Certified Inspector must sign the permit and should keep a copy for a permanent record.

7.        The BUSTR Closure Report is required after the UST removal has been completed.  The Contractor is required to submit the completed report to the Project Engineer within 30 days of the tank removal.  The Regulated Waste Project Engineer should sign and submit the Closure Report to BUSTR within 45 days of the tank removal.  The Regulated Waste Project Engineer may elect to have this closure report reviewed by an environmental consultant.

8.        The District is required to retain the Closure Report record in perpetuity.  The report should be given to the Regulated Waste Project Engineer and/or District Environmental Coordinator.  The Regulated Waste Project Engineer must ensure that these records are given to the District Environmental Coordinator for final record keeping.

9.        Depending on the result of the closure assessment, further investigation, risk assessment, and remedial action may be necessary. The District will determine if an Environmental Consultant will be needed to perform the assessment work.  A task order contract may be used to perform this work. 

10.     The specification requirements in 202.08 do not cover risk assessment, remedial action, environmental cleanup, or the cleanup of the contamination plume beyond a “few feet” outside the UST footprint.  If the assessment work is not described in the Plan Note, this work should be considered extra work.

Other Governing Agencies

The following personnel must be contacted when the UST is removed, and 25 gallons or more of petroleum are released, or if the product reaches a body of water or travels off the project site.  Project Personnel should use the following website during a release:

http://www.epa.state.oh.us/derr/ersis/er/er.aspx

1.        Immediate Notification:

a.        Regulated Waste Project Engineer.

b.        District Environmental Coordinator.

c.        Local Fire Department.

d.        The OEPA Emergency Response Unit at 800-282-9378.

2.        BUSTR Corrective Action Hotline at 800-686-2878 within 24 hours.

3.        Contact all of the following if a hazardous chemical in excess of its reportable quantity is released:

a.        Regulated Waste Project Engineer.

b.        District Environmental Coordinator.

c.        Local Fire Department.

d.        The Ohio EPA at 800-282-9378.

Reportable chemical quantities may be between 1 and 500 pounds depending on the chemical.  The website refers to Code of Regulation (CFR) that gives the reportable quantities limits.  In addition, it gives explicit instructions about what action should be taken by the project personnel.

The Contractor and the Regulated Waste Project Engineer should know the reportable quantities prior to the UST removal.

The District will determine if an environmental consultant will be retained to assist the District in regulatory compliance.

Regulated Waste Requirements

Importance

The Department has experienced contract administration problems during the disposal of regulated wastes, underground storage tanks and asbestos pipe, and administrating borrow and waste areas.  The main cause of these problems is the confusion regarding current regulations and new regulations, which govern construction debris, as well as the infrequency that some of these items are included in the contract.  The improper disposal or management of regulated materials can create substantial construction delay problems and a potential liability to the Department in the future.

Regulated waste, for the purposes of this manual, is defined as a hazardous waste, solid waste, construction and demolition debris, petroleum contaminated soil, or any other regulated material denoted for removal under the contract.  For further explanation regarding hazardous waste classifications, types, and characteristics, see the Hazardous Waste Management Program Manual or other Hazardous Waste Training Manuals.  

This section is to be used in conjunction with the Hazardous Waste Management Program Manual (HWMPM) and the handouts and manuals received in the 24- or 40-hour Hazardous Waste Operations and Emergency Response (HAZWOPER) training or the 8-hour HAZWOPER refresher courses.

Additional references can be found by reviewing the 8-hour Construction Safety or Construction HAZWOPER Manual.

This section does not expand on the technical, environmental details explained in other manuals.  This manual should be used as a reference to other manuals when technical details are needed beyond the scope of this manual.                      

Responsibility

Project Engineer and Regulated Waste Project Engineer (RWPE)

The person in charge of work on a construction project is called the Project Engineer.  A supervisor or an inspector may run the project on a daily basis depending on the District level of staffing for the project.  The Project Engineer will randomly check in on the project and make any engineering decisions.

The Regulated Waste Project Engineer (RWPE) is in charge of all removal operations of regulated waste on the projects.   The RWPE signs all manifests from the projects and ensures that all environmental documents from the project are transferred to the DEC for permanent storage. Each District will have at least two engineers working at this function.

In some Districts, the District Environmental Coordinator (DEC) or District Hazardous Waste Coordinator (DHWC) may substitute for the RWPE if the RWPE is not available.

Administering the Contract

The RWPE has the responsibility to effectively administer all aspects of regulated waste on the construction project.  They must familiarize themselves with the specifications, the Contract, and this section of the manual to perform their duties.  The RWPE makes interpretations of the regulated waste contract documents and this manual to the Project Engineer, Supervisors, or Project Inspectors.  In addition, the RWPE insures that trained inspectors are inspecting the work.

The RWPE’s main contacts for environmental advice are the District Environmental Coordinators (DEC).  The DEC coordinates with the District Hazardous Waste Coordinator, District Safety Representatives, Emergency Coordinators, and the Environmental Site Assessment Section in the Central Office of Environmental Services to make environmental decisions.

The following is a link to their names and numbers:

http://www.dot.state.oh.us/Divisions/Planning/Environment/staff/Documents/DEC_List.pdf

Reporting of Significant Changes

The Project Engineer is responsible for reporting any significant deviations in the Contract documents to the District Construction Administrator and/or the County Manager.  The Project Engineer has the authority to order the Contractor’s personnel and the Environmental Consultant to perform, “as directed work,” in all situations within the contract limits.  This authority is tempered with a great deal of responsibility for their actions.  If the Project Engineer orders work contrary to the recommendations of the RWPE, Environmental Specialist, or the Environmental Contractor, then the Project Engineer becomes personally liable for their actions.  Before making any final decisions, the Project Engineer must ensure that their instructions do not contradict any laws or regulations that govern the work.

Health and Safety Responsibilities

The RWPE, who has 24-hours Of HAZWOPER training, is responsible for the health and safety of the Department Inspection Forces.

Additional health and safety responsibilities are listed below:

1.        Ensures that project inspections are performed with adequate personnel, equipment, and resources to complete the inspections safely.

2.        Ensures that telephone communications between the Department Inspectors and emergency response personnel is maintained.

3.        Ensures that all inspectors are adequately trained and qualified to work at the site.

4.        Reviews the Site Specific Health and Safety Plan (SSHSP) and ensures that the SSHSP is adapted by the Department to include ODOT inspection forces.  For this review, the Environmental Consultant can be hired by third party billing through the Contractor or by the District Task Order Contract.

5.        Reviews the Contractor’s Site Specific Health and Safety Plan.  Do not accept the SSHSP for liability reasons.

6.        Provides oversight of the Contractor’s operations as it pertains to the Contractor’s SSHSP.

7.        Reviews the SSHSP with the Inspectors.

8.        Serves as the primary contact to review ODOT health and safety matters that may arise on the project.

9.        Informs the Inspectors of revised or new safety protocols for the field operations.

10.     Informs the Inspectors of revisions to the SSHSP.

11.     Reviews accident reports and the results of the inspections.

Project Inspector

The Project Inspector is responsible for the detailed inspection of the work and to follow the directions given by the RWPE, Project Engineer, and the SSHSP.

Contractor’s Responsibilities

The Contractor is responsible for prosecuting the work according to the plans and specifications.  The C&MS Section 107.01 explicitly states that the Contractor shall comply with the construction safety rules and regulations.  Employers are always responsible for the safety of their employees.

District Environmental Coordinator (DEC)

The DEC is responsible for giving technical advice to the RWPE, reviewing or hiring an environmental consultant to review the Health and Safety Plan for ODOT workers, and coordinating matters of safety and hazardous waste with the District Hazardous Waste Coordinator and District Safety Representative.

Training

General

Where the disposal of regulated wastes is necessary during construction, the District Construction staff must have knowledge beyond the plan note requirements in order to make appropriate and legally correct decisions when facing actual field mandated changes to the contract. 

An understanding of the requirements of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), the Resource Conservation and Recovery Act (RCRA), and Occupational Safety and Health Administration (OSHA) requirements is essential during the construction phase.

Training is available through the Office of Environmental Services in Central Office, Environmental Site Assessment Section (614-466-7942); Bureau of Workman Compensation, Division of Safety and Hygiene (800-644-6292); or through a variety of private training sources. The private training may be charged against the project on third party billing through the Contractor. 

The following is a link to the Bureau of Workman Compensation, Division of Safety and Hygiene for free training courses:

http://www.ohiobwc.com/employer/programs/safety/SandHCourses.asp

Nothing in this manual requires ODOT project personnel to enter a hazardous waste site without the consent of the employee.  All regulated waste removal work is performed by the Contractor and no ODOT personnel should actively participate in this work.

The majority of the regulated waste removal operations on highway construction projects consist of the removal of solid waste or petroleum-contaminated soil.  The minimum training requirements listed below should be observed for all regulated waste or underground storage tank removal projects.

Project Engineers

All Project Engineers are required to attend the 8-hour Construction Safety Awareness Class and the 8-hour Construction HAZWOPER Awareness Class.  This training will be given every three years.  This training will enable workers to recognize hazards or conditions that require further investigation by other more specialized personnel.

Regulated Waste Project Engineer (RWPE)

The District will designate at least two Project Engineers with 24-hour Construction HAZWOPER training.  The RWPE will deal with all regulated waste issues that arise on the projects.   An 8-hour annual refresher course is required.

Project Inspector

All Project Inspectors are required to have the 8-hour Construction Safety and 8-hour HAZWOPER Awareness Training.  Students who complete this training will be able to recognize hazards or conditions that require specialized training.

Consideration should be given to having a project inspector oversee the removal of underground storage tanks.  Certified Underground Storage Tank Inspector training can be obtained from BUSTR.  See Section 202 Removal of Structures and Obstructions.

Specialized Inspection

Additional environmental consultant inspectors may be hired through the Districts or Central Office Environmental Site Assessment Task Order Contract to provide specialized inspection.  The RWPE should contact the District Environmental Coordinator to obtain these services.  The procedure is further explained in the section, Obtaining Technical Advice or Inspection.

Medical Monitoring

Medical monitoring is required for employees working on hazardous waste projects who are:

1.        Exposed to contaminants above the permissible exposure limits (PEL) for more than 30 days per year.

2.        Wear a respirator for 30 days or more per year.

3.        Injured or become ill due to exposure to hazardous substances.

OSHA 29 CFR 1910.120 covers this requirement.  The SSHSP, the District Safety Coordinator, and the District Environmental Coordinator should be consulted to determine the need for medical monitoring of an employee.  Medical monitoring is rarely needed due to the type of contaminates, solid wastes, or petroleum contaminated soil normally encountered on highway construction projects.

Changes to the Training Requirements

The SSHSP may alter the above requirements because of the particular contaminants on the project.   Review Site Specific Health and Safety Plan Requirements and the project SSHSP.

Training and Medical Records

All training and medical records shall be kept according to sections 1105 and 1106 in the Hazardous Waste Program Manual (HWMPM).

Construction Safety Training

Confined space, trenching, excavation safety, and other construction related issues are covered by the 8-hour Construction Safety Awareness class.   The 8-hour Construction Safety Awareness Training will be offered to all construction personnel every 3 years.

Additional training is provided at no cost through the Bureau of Workman Compensation at 800-644-6292.  Any personnel who want extended training should take the following courses:

§  Trenching and Excavation, Course SAF112

§  Confined Space Assessment and Work, Course IHY214

These courses are offered at various times throughout the state.  Construction personnel can sign up for the courses at the following website:

http://www.ohiobwc.com/employer/programs/safety/SandHCourses.asp

Site Specific Health and Safety Plan Requirements

The Contractor is required by OSHA and the contract documents to have a Site Specific Health and Safety Plan (SSHSP) when working within the exclusion or contamination zones of a construction project.  Depending on the material contents of an underground storage tank, these exclusion zones may include the areas around the removal of underground storage tanks.

The Contractor is responsible for the health and safety of their personnel. The Contractor is required to have the SSHSP available at the project site for inspection.  In no case will the Department accept or approve a Contractor’s SSHSP. 

Under C&MS 105.10, the Contractor must provide access to Department personnel to perform work inspections.  The Contractor cannot restrict the inspection of the work when the inspection forces meet the minimum training requirements of the SSHSP.

The RWPE is responsible the health and safety of the inspection personnel.  See “Health and Safety Responsibilities” in the Responsibility section of this manual.   The RWPE may forward the Contractor’s SSHSP to the District Environmental Coordinator (DEC) for review.  The DEC will note how the SSHSP affects the qualifications of the inspection forces.  The RWPE, in consultation with the DEC, will determine whether department forces or consultant forces should inspect the work.  If consultant inspectors are used, the consultant will be responsible for the health and safety of its employees.

Minimum Contents of the SSHSP

The SSHSP will contain the following information:

1.        Safety and Health Risk or Hazard Analysis.

2.        Employee Training Assignments.

3.        Personal Protective Equipment Requirements.

4.        Medical Surveillance Requirements.

5.        Frequency and Types of Air Monitoring.

6.        Site Control Measures.

7.        Decontamination Procedures.

8.        An Emergency Response Plan.

9.        Confine Space Entry Procedures (if necessary).

10.     Spill Containment Program.

Further information about the SSHSP is detailed in the 24-hour training for the Regulated Waste Project Engineer.

Obeying the SSHSP Requirements

All construction personnel, including ODOT project personnel, will work under, and obey the requirements of the SSHSP during the inspections.  The project personnel should review the SSHSP to become familiar with all the aspects of this document.

All ODOT personnel entering the contamination zone must wear the personal protective equipment (PPE) listed in the SSHSP.  The training and equipment may be obtained by contacting the District Environmental Coordinator or Safety Coordinator.  If the required equipment and training are not available to ODOT personnel, then this training may be paid for under third party billing through the Contractor.

Absence of a SSHSP

In the absence of a project SSHSP, the RWPE should contact the District Environmental Coordinator to determine the need for an SSHSP.  There will be instances where an SSHSP is not required.  Some solid waste or petroleum contaminated soil operations will generally not require an SSHSP.

Regulated Waste Designated for Removal in the Contract

General

Most hazardous waste sites are identified through environmental site assessment during the preliminary development process.  These sites are avoided where possible.  When these sites cannot be avoided, plans or notes will be placed in the contract to instruct the project personnel how to safely remove, cap, or remediate the contaminated material.  Some typical plan notes are shown in the section, Typical Regulated Waste Plan Notes, of this manual.

Projects involving the removal of regulated material may quickly become complicated from an administrative perspective.  The District Planning and Production staffs should coordinate the plan notes and specialized requirements for each project with the District Construction staff to ensure that the construction inspection staff, including the Project Engineer, understands why the special notes are in the plans and what special administrative requirements are necessary.  If necessary, time should be allotted to develop contracts for outside environmental inspectors and to determine if specific training is needed for ODOT inspectors.

Construction projects with complicated remediation work, which requires specific equipment, project staff, or time, may be separated from the highway construction project to avoid overly complicating the project.  Proper management and disposal or remediation of regulated waste and USTs are essential to prevent future liability for the Department.

The Contractor is responsible for the proper removal of regulated waste.  The project personnel are responsible to control the Contractor’s work according to the contract documents and all applicable laws and regulations.

Reference Material for Regulation Requirements

The Hazardous Waste Program Manual is an excellent reference to help the project personnel to familiarize themselves with the regulation requirements and the waste types, characteristics, and generation requirements.  Consult the 24-hour Construction HAZWOPER training manual when dealing with these regulated wastes.

Plan Notes

The plan notes and/or environmental site assessment reports are available to the project construction personnel to help familiarize them with the type of contamination that will be encountered on the project.  These reports should be available through the DEC, production, or the Office of Environmental Services in Central Office.

The specialized plan notes may require department or consultant environmental inspectors to field screen samples and analyze soils excavated from areas of environmental concern.  Contractors may be required to stockpile, containerize, or dispose of contaminated soils.  The plan notes should allow the project to efficiently manage the disposal of the regulated wastes and/or USTs encountered on the project.  

The plan notes will outline who is responsible for what operation on the project.  The RWPE should review the plan notes before the Contractor starts work.  The following is a general outline of responsibilities.

Pre-Excavation Checks

The regulated wastes are usually located on the plans.  Work can begin in these areas once the Project Engineer is satisfied that all of the following are complete:

1.        The SSHSP is present on the project.

2.        The Department has appropriate environmental inspectors.

3.        The Contractor has the appropriate work force to proceed with the work.

4.        The Contractor has set up the appropriate zoning as noted in the SSHSP.

The zoning includes, but is not be limited to all of the following: Contamination Zone, Decontamination Zone, and the Safe Zone. These areas must be secured at all times and are usually separated by a construction fence. 

Excavation

Contamination areas are sometimes marked in zones designated as hazardous, solid, or other waste classifications.  This gives the Project Engineer an insight into the general classification of the material in the contamination zones.  This classification is generally not used for final disposal.  The Environmental Inspector may field screen the regulated material prior to the stockpiling, but all materials are stockpiled and tested prior to the final disposal of the material.

In some cases, and with the permission of the regulatory agency and the District Environmental Coordinator (or as allowed by the plan notes), the material may be excavated and directly placed in trucks for disposal at the landfill.  This may require additional testing of the excavation area.  Substantial savings may be obtained when this method is used. 

The plans generally call for the removal of enough material to build the highway.  Unless otherwise called for in the plans, the Department does not clean up all the regulated material in the right-of-way.  Contact the District Environmental Coordinator for cleanup instructions, unless a regulatory authority is overseeing this portion of the project. 

Temporary Storage

The contract documents give general details about the temporary storage methods.  The RWPE should review the Contractor’s proposed storage method and determine if the proposed method meets the intent of the plans.  The project should review the storage locations daily to ensure the work is progressing satisfactorily.  A sample inspection form is in the Hazardous Waste Management Program Manual (HWMPM) in appendix k.  When work is not in progress, all storage areas must be inspected weekly, as per Section 507 in the HWMPM.

Material Sampling

The Contract or Plan may require that the State’s Environmental Consultant or Contractor’s Environmental Specialist test the regulated waste after it is stockpiled.  The testing amount and location will be detailed in the plan or determined by the Environmental Consultant.

ODOT employees should not test or sample suspected hazardous waste material. This should be done by an environmental consultant.  The Contractor is responsible for any other tests required by the landfill for disposal purposes.  The Contractor is required to give all the test results to the project.

The test results shall be kept according to Section 1104 in the HWMPM.

Evaluation

Once the material is tested and the results are known, the material may be classified into a regulatory category, such as hazardous waste, solid wastes, petroleum contaminated waste, special, or non-regulated wastes.  The material may be shipped to the appropriate landfill or onto other areas of the project if allowed.  Petroleum contaminated soil is allowed under 203.02.K to be used as fill.

Manifesting

The manifest documents must be filled out and completed prior to the disposal of any hazardous waste material.  Manifest documents are prepared by the Contractor and signed by the RWPE on behalf of the Department. 

The RWPE receives one copy of the manifest; the remaining copies go out with the trucker. 

The destinations of the various copies of the Manifest are as follows:

1.        Landfill: Original signed copy.

2.        Project: First copy signed by Landfill.

3.        Contractor: Second copy signed by Landfill.

4.        Trucking Company: Third copy signed by Landfill.

5.        Project: Fourth copy kept by the Regulated Waste Project Engineer (RWPE) after they sign the manifest; it does not go with the load.  The RWPE matches it with the Landfill signed first copy that is returned to the Project.  The RWPE verifies that the two copies match.

The manifest form has these terms for the various parties:

Party

Form Term

Landfill

DESTINATION

ODOT Project

GENERATOR

Contractor

OPERATOR

Trucking Company

TRANSPORTER

There are four carbon copies, so the RWPE musty sign the forms with a lot of pressure.

One copy of the manifest comes back to the project when the regulated material is disposed at the regulating facility.  The RWPE must ensure that all copies and material quantities are accounted for in a timely manner.  See Section 603 in the Hazardous Waste Management Program Manual for information about the action to be taken when a manifest does not come back to the project.

Examples of Manifests and a full description are shown in the Hazardous Waste Management Program Manual (HWMPM) in Section 602.  Most of the regulated material removed from construction projects will be either petroleum contaminated soils or a solid waste.   Manifesting is required, but there will not be an RCRA generator number on a solid waste manifest.  An example of one is on Figure 202-1.

Figure 202.A – Non-Hazardous Manifest

For more information regarding manifesting, see Sections 603 and Appendix I of the HWMPM. 

Pre-Transportation Requirements and Placarding

The Hazardous Waste Management Program Manual (HWMPM) is an excellent resource to determine the pre-transportation and placarding requirements.  Sections 504, 605 and appendix P of the HWMPM provide a pre-transportation requirements and checklists.  The Contractor is required to provide all of the material and manpower to provide for the proper identification, transportation, and disposal of the regulated waste.  The RWPE must ensure that the packaging, labeling, and placarding are done according to the regulations.

Records of the Disposal

All documentation of the regulated waste operations should be recorded in SiteManager and in the daily diaries.  All records should be kept with the project files. The Regulated Waste Project Engineer must ensure that the records are kept in the District for future reference. The records need to be kept by the District Environmental Coordinator in the District.

If regulated waste is classified as a hazardous waste, then all of the records keeping requirements listed in Section 1101 in the HWMPM apply. 

Weekly Project Inspections

When the project conducts hazardous waste removal operations, then the RWPE will perform the weekly inspection requirements in 1107 in the HWMPM.

Regulated Wastes Found During Construction

General

Special procedures must be followed when the Contractor encounters potential regulated materials that were not anticipated by the plans.  Section 203.04 of the C&MS describes the process for notifying Contractors and Department personnel of these special procedures. 

Limit Access to the Suspect Area

Suspected regulated material must be left in place until identified by a qualified specialist.  This may require the temporary discontinuance of work in the area of the suspected materials.  The area in question should be secured to prevent access.  This can be accomplished by cordoning off the area with rope or construction fence and posting a guard.  On large projects, work may continue at locations sufficiently removed from the site in question.

Notification

The Project Engineer must be notified immediately and should contact the RWPE.  The Department will evaluate the level of risk to workers and the public, and notify all responsible parties and regulatory agencies as required.  The District will consult with the appropriate environmental regulatory agencies and ODOT staff with specialized expertise in the hazardous waste field in the Office of Construction Administration, or the Office of Environmental Services, to determine a course of action.  If it is determined that the area in question is or may be contaminated with environmentally regulated substances, the District will initiate the evaluation and remediation of the problem area as described below. In the event of a life-threatening situation to human health outside the project, contact the Local Fire Department and the Local Police.  Report the incident to the District Construction Administrator and the Highway Manager to determine if local involvement is required.  When local involvement is required, notify the County Emergency Manager Director listed in the current version of the Incident Management System Responders Listing.

Releases

If a hazardous chemical in excess of its reportable quantity is released into a body of water or leaves the project site, all of the following must be notified:

1.        RWPE or DEC.

2.        Local Fire Department.

3.        The Ohio EPA at 800-282-9378.

Reportable chemicals may be between 1 and 500 pounds depending on the chemical.  The following website refers to the Code of Regulation (CFR) that gives the reportable quantities limits.  In addition, it gives explicit instructions about what action should be taken by the project personnel:

http://www.epa.state.oh.us/derr/ersis/er/er.aspx

The project should hire an environmental consultant to help with required paperwork and technical advice.

Obtaining Technical Advice or Inspection

It is imperative that action be taken to mitigate the problem in a timely manner.

If required, the District may seek the services of a qualified consultant who specializes in regulated waste assessment and remediation, and billing through the Contractor or the District or Central Office task order contract.

The District or Central Office Environmental Site Assessment Task Order Contract can be used to provide specific environmental expertise for the consultation, evaluation, and testing in these situations.  The District's Planning and/or Environmental staff can aid in developing a proposal request for these services when the Task Order Contract is used.  This can be provided at no cost to the project.

The specific consultation, testing, or inspectors hired through the Task Order Contract or other contracts should specify the type of environmental expertise needed.  For example, a project involving underground storage tanks or petroleum contaminated soils requires knowledge of BUSTR rules and regulations, operation of organic vapor analyzers, and the ability to interpret laboratory data.  A good minimum qualification for these projects would be a Certified Installer or Inspector under BUSTR’s rules.  Projects involving hazardous solid wastes or other types of wastes require the appropriate type of expertise.

Development of the Remediation or Disposal Plan

The chosen environmental consultant must submit a sampling plan for the Department and OEPA (if applicable) for approval.  Upon approval, the environmental consultant will perform the required sampling, testing, mitigation, and possible disposal.

If it is determined that no contamination exists, or that the problem has been resolved on the site, the Contractor will be directed to return to work.

If required, the Environmental Consultant or Contractor will develop a removal or remediation plan in consultation with ODOT, OEPA, or BUSTR (if applicable).

Implementing the Plan

Once the contaminant is known, and a plan to eliminate or mitigate the regulated material is determined, the Department may seek competitive bids from a qualified regulated waste disposal firm contractor to remove or mitigate the waste.

If the project cannot tolerate the time it would take to obtain competitive bids, the Department may request a waiver of competitive bidding from the Controlling Board and award it to an approved, qualified environmental firm via third party billing through the Contractor.

Where treatment or disposal of the regulated material must be conducted concurrently with construction, it may be made a part of the construction contract.

Disposal and Remediation

A remediation contract will be initiated once all the approvals are obtained. The Environmental Consultant, Contractor, or Subcontractor will perform work according to this manual and the approved remediation plan.

The Department will keep complete records of all activities performed in the treatment, removal, transport, and disposal according to all applicable laws, rules, and regulations.  These records are the same as detailed in the Regulated Waste Designated for Removal in the Contract section of this manual.

All of the disposal requirements of a regulated waste outlined in the Regulated Waste Designated for Removal section in the Contract still apply.  A plan note, similar to the ones in the Typical Regulated Waste Plan Notes section of this manual; an excavation plan; and a SSHSP should be developed before the work begins.

Other Wastes and Environmental Considerations

It is important to be aware of other common construction materials that can cause environmental problems during or after construction. The most common materials are construction and demolition debris, landscape waste (buried or burned on-site), and asbestos pipe.  These materials were detailed in Sections 105.16, 105.17, 201, and 202.  Other materials such as slag, scrap tires, railroad ties, and recycled materials are detailed in this section.

Slag Use on the Projects

Air-Cooled Blast Furnace Slag

Air-Cooled Blast Furnace slag (slag made from making iron) has been known to produce a green, yellow, white, or black runoff, which can smell like rotten eggs.  The color is usually pH driven and goes away in about six months, but not always.  The runoff may exceed the allowable pH limits under the Clean Water Act.

To minimize these problems, all Air-Cooled Blast Furnace slag must pass the Sulfur Leachate Test detailed in Supplement 1027.

The problems first showed up in Cleveland around 1992.  The Ohio EPA wanted the slag industry to regulate themselves and change the ACBF slag chemistry by adding chemicals.  This did not work well, and in 1998, the Ohio EPA requested that the Department specify the Bucket Test.  The Bucket Test was pre-2002 SS-907 and was successfully used in Chicago.  The Bucket Test can detect if the sulfur content in the slag is too high.  The Bucket Test was implemented by SS-907 in 1998.

Then the Ohio EPA found several more projects with environmental problems.  One of the projects was ODOTs.  This Department project used RPCC (Recycled Portland Cement Pavement) and ACBF slag.  The RPCC was used in the undercut and the ACBF Slag was used in the 304 material.  The Department was cited for violating the Clean Water Act.  This problem has cost approximately $120,000 and has led the Department to hire an Environmental Consultant to remediate the problem.

The environmental problems on non-ODOT projects were clearly caused by the ACBF slag.  One of the projects cost millions of dollars to remove the ACBF slag due to environmental problems.  Another project has cost thousands of dollars a month to contain and remove the runoff.  By reviewing the Ohio Administrative Code, environmental reports, and performing lab tests, ODOT developed the following solution in Supplement 1027:

1.        Lengthen the time of the Bucket Test.

2.        Incorporate some of the Ohio Administrative Code Water Quality requirements.

3.        Test for pH, conductivity and total dissolved solids.

These tests will minimize ODOT’s environmental liability.  It is important that the project personnel recognize these requirements and only use materials that meet these specifications.

Steel Slag

Steel slag can expand and produce tufa, which can block underdrains.  All steel slag is restricted in 703.01.E and 703.14 in the C&MS. 

There are three types of slag detailed in these specifications: Open Hearth, Basic Oxygen Furnace, and Electric Arc slag. All slags are byproducts of making steel or iron.  Open Hearth slag (OH slag) was produced pre-1970.  Basic Oxygen Furnace slag (BOF slag) and Electric Arc Furnace (EAF slag) are produced from a newer and faster process for making steel. Basic Oxygen Furnace slag tends to have more problems than Open Hearth slag because the OH process is slower, and the slower process burns more chemicals out of the OH slag.  Very little Electric Arc Furnace slag was used for ODOT work, but it has more detrimental effects than any of the other steel slags.

Background on Open Hearth and Basic Oxygen Slag Restrictions

In the mid-1970s, the Department had severe expansion problems associated with bedding, backfill, and base material placed using OH and BOF steel slag.  This problem caused the Department to spend hundreds of thousands of dollars due to premature failures.

As result of several years of research, the Department required a 6 month aging of all OH and BOF slags to solve the problem.  It also eliminated the use of OH or BOF slags in confined areas such as pipe bedding and backfill, underdrains, and around structures.

In the late 1970’s and early 1980’s, OH and BOF slags were found clogging up underdrain systems. The use of OH and BOF slags was eliminated in Items 310 and 304.

In the early 1990’s, the Department allowed the use of some OH slags if the field performance proved that the OH slag did not block underdrains.

In the 1997 specification book, the Department allowed OH slag in Items 203, 307, 306, 304, 410, 411, 603, and 617.  BOF slag was allowed for Items 203, 410, 411, and 617.  The following is some of the reasoning behind the 1997 and 2002 specification changes.

1.        We consulted with Industry, Illinois, Indiana, Pennsylvania, and the Ohio Turnpike on this matter. ODOT reviewed past research and consulted with John Hurd, Stu Schwotzer, and Phil Hall who performed the majority of the research done in the past.

2.        The words, “from sources on file at the Laboratory,” have been misinterpreted in Items 304, 410, 411, and 617. The intent of this note was to verify tufa performance before the sources are used. This has been clarified. 

3.        The expansion potential of OH and BOF slags are related to the concentrations of CaO and MgO. CaO leaches out during the aging process, while MgO may not.  A test method is recommended to help determine the expansion risk.  The recommended expansion test has a 20-year field performance related history.

4.        The risk is too great to allow BOF slag in base material. Therefore, clear identification of OH slag is critical to base performance.  A procedure to verify the material source as OH slag is detailed.

5.        Water and confining pressures cause additional expansion potential in OH and BOF slag. Therefore, all OH and BOF slag was eliminated in areas where the material is confined.

Summary

The problems found in the mid-1970’s were primarily from projects built in the mid-1960’s.  Tufa was not found blocking underdrains for about 10 years.  Problems associated with ODOT projects built today may not arise for 10 years or more.

The easiest way to avoid problems is to eliminate the use of OH and BOF slag in all Department items of work. Certainly the Department has documented enough bad performance related problems associated with OH and BOF slag to justify this elimination.

Most states do not allow steel slag for any base or confined areas.  Instead, we have implemented a method and procedure that allows the use of OH and BOF slag in certain applications to minimize the potential for premature failures.  

The restrictions on the use of OH and BOF slag are intended to ensure we do not revisit those past expansion and tufa problems.  Using materials that comply with the specifications minimizes environmental and engineering concerns.

Tufa Removal

Lime precipitant from slags used in the bases of older projects can create deposits that form on the side slopes.  The deposited material will have a high pH and may have to be taken to a solid waste landfill.  The material may be a hazardous waste if the pH is above 12.5.

When the project personnel notice these materials within the project limits, the deposits should be tested and removed as follows:

1.        This material should be tested under the task order contract.

2.        The Contractor should perform the removal by force account.

Some projects may have special plan notes for the removal operations. The following plan note will be used to remove the tufa.  If a large amount of tufa is on the project there may be other removal notes. 

Environmental Work General Tufa Note (11/28/01)

A field review has determined that there are tufa deposits located between stations ______and stations _______ at the underdrain outlets.   If these materials are encountered, manage this material according to the following.

Obtain all necessary testing for disposal, permits and approvals, and transportation of the material to a licensed (by the local health department) and permitted (by the state environmental protection agency) solid waste disposal facility.

Provide areas to stockpile the material.  Stockpile the materials in a leakproof and covered container.

Ensure that all transport vehicles used for the movement of regulated material meets all applicable Local, State, and Federal requirements.  Maintain records (such as manifests, landfill tickets, daily logs, etc.) to document the source, movement, and destination of each truckload of contaminated material.  Submit one copy of each of these records to the Engineer.

Furnish all the labor, equipment, and materials necessary to excavate, store, test, transport, and dispose of the tufa material, including any required permits, approvals, or fees, within the aforementioned limits.

The Department will pay for this work according to 109.05 (C&MS).

Scrap Tires

Scrap Tires found on the project are transported under OAC 3745-27-56.  The tires must be disposed of at a registered and permitted scrap tire facility as per OAC 3745-27-61 thru 65.

Use the following link to the OAC:

http://codes.ohio.gov/oac

Under these requirements, the transportation company and the disposal facility are regulated by the OEPA.  Shipping papers are required to ship the tires to and from the facility. The District Environmental Coordinator or 24-hour trained Regulated Waste Project Engineer will sign the shipping papers for the Department.  The records must be kept for 3 years.

Railroad Ties

The Ohio EPA encourages the use of railroad ties as landscape materials or other uses. When disposed, they are disposed of in a construction and demolition debris site or a solid waste facility.

To date, creosote in railroad ties does not pose an environmental threat.

Recycled Materials

Supplemental Specification 871 allows the use of fly ash, bottom ash, foundry sand, glass, and tires in fills.

Recycled materials are defined in the C&MS in 203.02.N   Recycled materials may be fly ash, bottom ash, foundry sand, glass or tires. 

Under certain circumstances, petroleum contaminated soil in 203.02.K may also be used in fills.  The environmental requirements are in 203.03.I on page 101 and 102.

The recycled materials are allowed in the interior sections of the fills. The approval on existing contracts will be on a case-by-case basis or if SS-871 is in the Contract.  Recycled materials are not allowed under the terms of the Contract unless SS-871 is included.

The following Designer Note should be reviewed prior to considering the use of Supplemental Specification 871 Embankment Using Recycled Material:

The specification was written to allow the Districts to use recycled materials in embankment construction. It was written to safely use these recycled products without jeopardizing the embankment or pavement integrity or long-term performance.  The Department does not require the use of recycled materials because this specification does not eliminate all risk or liability to the Department.  It only minimizes these risks. The utilization of SS-871 is at the District’s discretion.  Districts are advised to consider all the benefits and potential problems prior to allowing these materials.

Benefits

Recycled materials can be cheaper and provide engineering improvements to the embankment construction.  For example, fly ash and tires can provide lighter weight materials.

By using these materials, the Department will save landfill space in the state.  The Department may minimize potential legislation in the future that would require the use of these materials.  (Note: In 1995, the state legislators required ODOT to allow petroleum-contaminated soil for embankment material, now under 203.02.K).

Potential Problems

Once these materials are placed on ODOT property, the recycled materials become the responsibility of the Department.  ODOT will assume any future liability and costs for removal and proper disposal of material according to future EPA regulations.  If this embankment is repaired in the future, the material may have to be disposed of in a landfill if required by Ohio EPA regulations.

A small percentage of tire fills have spontaneously caught fire.   Fly ash is a silt and may be susceptible to frost heave and capillary action.  Both problems are minimized by the engineering controls in the specification.

The District may pick and choose which recycled material to use or they may allow the use of all recycled materials.

The District may allow different materials at certain locations along the project.

No change in the cross sections is needed to include SS-871 in the plans.  This specification delineates the areas in which recycled materials are allowed.

The following plan note can be used to incorporate SS 871 in the contract.

Embankment Construction Using Recycled Materials

On this project, Supplemental Specification 871 Embankment Construction Using Recycled Materials applies.  ____________________________ (Put in the materials wanted or needed) may be substituted for Item 203 Embankment in the contract.  The Department will measure and pay for all work detailed in SS-871 according to the Unit Bid Price for Item 203 Embankment.

Typical Regulated Waste Plan Notes

Typical Plan Note for: Non-Regulated Materials, Petroleum Contaminated Soil and Underground Storage Tanks

ENVIRONMENTAL WORK

1. Introduction

Soil adjacent the New Hamlet Cleaners property (SE corner of SR 132 and SR 125) was tested and contained petroleum substances.  These substances are present within the excavation limits for proposed underdrains, proposed 36-inch storm sewer, other utilities and/or roadway construction from Station 1+50 Lt. along SR 132 Station 370+70 Right along SR 125 (see Sheet 22/57).  This material must be handled by the Contractor according the following notes.  In addition, the Contractor shall remove four underground storage tanks located within the proposed right-of-way limits in accordance with Item 202 of ODOT’s Construction and Material Specification (C&MS).

1.2 Site Specific Health and Safety Plan (SSHSP)

The Contractor shall certify in writing to the Engineer within 2 weeks after contract execution that the Contractor has prepared a SSHSP in accordance with OSHA 29 CFR Part 1910.120 for operations involving hazardous substances within the aforementioned limits.  The Contractor shall make the SSHSP available at the project site.  Copies of the environmental studies are available for examination in the Office of Contracts and the ODOT District 12, Office of Planning. This information may be used by the Contractor to develop the SSHSP.

1.3 Material Sampling

The Contractor shall provide the Engineer with 5 days’ notice prior to beginning any excavation within the aforementioned limits to permit arranging for the necessary testing services. All material excavated by the Contractor between these limits during construction shall be subject to testing by an Inspector provided by the Engineer.  The Inspector shall field-screen the excavated material for petroleum contamination using an organic vapor analyzer (OVA).  At the discretion of the Inspector, the excavated material, which exhibits petroleum contamination, shall be stockpiled and segregated while samples of the material are analyzed by an independent analytical laboratory.  Field-screening results and visual observation will be the basis for segregating excavated material. Soil samples shall to be tested for BTEX (Benzene, Toluene, Ethyl benzene, and Xylene) by Method 8020 and TPH by Method 8015.  If the BTEX and/or TPH levels exceed levels set forth by the Ohio EPA Petroleum Contaminated Soil Policy, the material shall be treated as petroleum-contaminated soil.  All field-screening instruments and initial sampling and analysis of soils will be provided by the Engineer at no cost to the Contractor.

1.4 Temporary Storage of Contaminated Soils

All excavated material, which is determined to be potentially contaminated with petroleum substances, shall be stockpiled in an area provided by the Contractor and approved by the Engineer.  The Contractor shall stockpile the material in a leak proof, covered container provided by the Contractor.  The material shall remain on-site until analytical results are received by the Engineer.

As an alternate, the Engineer may permit temporary storage of suspected contaminated soils on an impermeable membrane.  The membrane should be surrounded by bales of straw to prevent the suspect soils from coming in contact with the original soils.  An impermeable membrane shall be placed over the stockpile to prevent contact with precipitation and/or surface run-off.

1.5 Material Evaluation

The Inspector shall use the analytical results to determine the regulatory classification of the excavated materials.  The excavated material may be classified in one or all of the following three categories:

1.5.1        ITEM SPECIAL - Work Involving Non-regulated Materials

The Inspector will determine if the excavated material is non-regulated.  The work involved in this Item Special includes developing and complying with a SSHSP; handling, storage, and disposal/use of non-regulated materials.  This material may then be used as backfill for other project purposes, if it meets the appropriate ODOT specifications.

1.5.2        ITEM SPECIAL - Work Involving Petroleum-Contaminated Soil

The Inspector will determine if the excavated material is petroleum-contaminated soil (PCS) based on the analytical test results.  The Engineer will provide the Contractor with these test results.  The Contractor shall be responsible for obtaining all necessary permits and approvals and to transport the material to a licensed (by the local health dept.) and permitted (by the Ohio Environmental Protection Agency) solid waste facility or a Petroleum Contaminated Soil Remediation Facility (PCSRF) for proper disposal or remediation.  Prior to disposal, the Contractor shall contact the proposed facility to determine the additional testing required for disposal or remediation at that facility.  The prices for these tests are to be included in the above pay item.  The work involved in this pay item includes developing and complying with a SSHSP; handling, storage, testing (for disposal or remediation); and disposal or remediation of PCS.  When directed by the proposed facility, the Contractor shall have an independent laboratory collect samples and test the excavated or stored materials for PCS disposal or remediation approval.

1.5.3        Work Involving Hazardous Waste

In the event the analytical test results for disposal purposes show the excavated material is a hazardous waste, disposal of this material shall to be paid for in accordance with Section 109.04 of ODOTs C&MS.

1.6 Backfill of Excavated Areas

All excavated areas shall be backfilled with suitable material in accordance with the project plans, applicable ODOT specifications, and/or as directed by the Engineer.  All surplus or unsuitable excavated material that can be used in embankments shall be disposed of in accordance with Item 203.05 of ODOTs C&MS.

1.7 General Notes

All transport vehicles used for the movement of regulated soils and/or water shall meet applicable local, state, and federal requirements.  The Contractor shall maintain records such as daily logs, landfill tickets, manifests, etc. that document the source, movement, and destination of each truckload of contaminated soil.  One copy of each of these records shall be submitted to the Engineer.

1.8 Basis of Payment

The Contractor shall furnish all the labor, equipment, and materials necessary to properly develop and comply with a SSHSP, excavate, store, test (for disposal), transport, and dispose of contaminated materials, removal of underground storage tanks, including any required approvals or fees within the limits identified above.  Payment for this work shall be made at the contract prices bid per ton and per regulated underground storage tank.  Work involving hazardous waste shall be paid for in accordance with Section 109.04 of ODOTs C&MS.

The following estimated quantities have been included in the General Summary for the work noted above:

Item Special - Work Involving Non-regulated Materials, 160 Ton

Item Special - Work Involving Petroleum-Contaminated Soil, 160 Ton

Item 202 - Regulated Underground Storage Tank Removed, 4 each

Typical Plan Note for: Solid Waste, Water, and Regulated Water

ENVIRONMENTAL WORK (CUY - Aerospace Parkway, PID 16802)

1.1 Introduction

Environmental studies have shown that regulated material (foundry sand, etc.) is present within the following excavation limits:

All excavations within the aforementioned limits shall be paid for under the original plan bid items.  The Contractor shall manage this material according to the following notes.  The estimated quantity has been included in the General Summary for this work.

1.2 Site Specific Health and Safety Plan (SSHSP)

The Contractor shall determine if a SSHSP is required in accordance with 29 CFR Part 1910.120.  Environmental studies information is available for examination at ODOT District 12, Planning Dept., 5500 Transportation Blvd., Garfield Heights, OH  44125.

1.3 Material Handling

All material excavated by the Contractor between these limits may be stockpiled in an area provided by the Contractor and approved by the Engineer.  The Contractor shall stockpile the material in a leak proof, covered container provided by the Contractor.

The Engineer may permit temporary storage of the regulated soils on an impermeable membrane.  The membrane shall be surrounded by bales of straw to prevent the suspected soils from coming in contact with the original soils.  An impermeable membrane shall be placed over the stockpile to prevent contact with precipitation and/or surface run-off.

As an alternative, the Engineer may permit the Contractor to direct load the excavated regulated soils (located within the aforementioned limits) into trucks for subsequent disposal.

1.4 Material Sampling and Disposal

The Contractor shall provide the Engineer with 5 days’ notice prior to any excavations within the aforementioned limits to permit arranging for the necessary testing services.  All material excavated by the Contractor between these limits shall be subject to testing by an Inspector provided by the Engineer.  The Inspector will conduct sampling and testing every 100 cubic meters of material excavated.  Samples will be tested by the following USEPA test methods:

The Contractor shall properly transport and dispose of the excavated material that is considered surplus or unsuitable material in a licensed (by the local health department) and permitted (by the Ohio Environmental Protection Agency) solid waste facility.  If required by the solid waste facility, the Contractor shall be responsible for conducting any additional sampling and analysis of the excavated material.

In the event the analytical test results for disposal indicate the excavated materials are hazardous and/or TSCA waste, disposal shall be paid for in accordance with Section 109.04 of ODOT’s C&MS.

1.5 Backfill of Excavated Areas

All excavated areas shall be backfilled with suitable material in accordance with the project plans or as directed by the Engineer.

1.6 Potential Dewatering Of Excavated Areas

If excavations within the aforementioned limits require dewatering for construction purposes, the Contractor shall dewater and subsequently dispose of waters by methods approved by the Engineer.  All water containerized by the Contractor between these limits shall be subject to testing by an Inspector provided by the Engineer.  Samples will be tested by the following USEPA test methods:

1.        The Contractor shall obtain all the necessary permits and/or authorizations needed to store, transport and dispose of the water in accordance with applicable local, state or federal regulations.

2.        The Engineer will classify the water removed from the excavation into one of the two following categories.

1.6.1        ITEM SPECIAL - Work Involving Water

The Engineer will determine if the water is non-regulated.  The method for disposing of the non-regulated water shall be approved by the Engineer.  Work involved with this Item Special includes the handling, storage, and disposal of the non-regulated water.

1.6.2        ITEM SPECIAL - Work Involving Regulated Water

The Engineer will determine if the water is regulated.  The Contractor shall be responsible for disposal of the regulated water.  The method for disposing of the regulated water shall be approved by the Engineer.  The work involved in this Item Special includes the handling, storage, testing, and disposal of regulated water.

1.7 General Notes

All transport vehicles used for the movement of regulated soils shall meet applicable Local, State, and Federal requirements.  The Contractor shall maintain records, such as manifests, landfill tickets, daily logs, etc., to document the source, movement, and destination of each truckload of contaminated soil.  One copy of each of these records shall be submitted to the Engineer.

1.8 Basis of Payment

The Contractor shall furnish all the labor, equipment, and materials necessary to properly handle, store, test, transport, and dispose of regulated materials, including any required permits, approvals, or fees within the limits identified above.  Payment for this work shall be made at the contract price bid per metric ton and/or cubic meter.  The basis for conversion from cubic meter to metric ton is 2 metric ton/cubic meter.  The following estimated quantities have been included in the General Summary for the work noted above:

 690M65010 Item Special - Work Involving Solid Waste, Mton

690M65020 Item Special - Work Involving Water, Cubic Meter

690M65024 Item Special - Work Involving Regulated Water, Cubic Meter

Typical Plan Note for: Ground Water Monitoring, Regulated Underground Storage Tanks and Scrap Tires

Environmental Work (HAM - 127 - 5.47, PID 9135)

Abandonment of Ground Water of Monitoring Wells

A total of three monitoring wells are present on the vacant lot located at 4135 Virginia Avenue (corner of Chase and Virginia).  These wells shall be abandoned in accordance with the Ohio Department of Natural Resources’ (ODNR) Technical Guidelines for Sealing Unused Wells (Appendix 4, Sealing Monitoring Wells and Boreholes).  Payment for this work shall be as per Item Special - Ground Water Monitoring Well Abandonment.

Removal of Underground Storage Tanks

The Contractor shall remove two petroleum underground storage tanks in accordance with ODOT Construction and Material Specifications (C&MS) Item 202.  These tanks are located at 4135 Virginia Avenue (corner of Chase and Virginia).

Removal and Disposal of Scrap Tires

Scrap tires are located throughout the project area.  The Contractor shall be responsible for removing, transporting, and disposing of these scrap tires as per this plan note.

The Contractor shall ensure that the tires are removed and transported in a manner that satisfies all the appropriate OEPA regulations.  Specifically, the transportation of tires is governed by OAC 3745-27-56.  The disposal of tires shall be at a registered and permitted scrap tire facility as per OAC 3745-27-61 thru 65.  Payment for this work shall be as per Item 202 Removal Miscellaneous:  Scrap Tires.

Basis of Payment

The Contractor shall furnish all the labor, equipment, and materials necessary to perform the aforementioned work.  The following estimated quantities have been included in the General Summary for the work noted above:

Item Special - Ground Water Monitoring Well Abandonment, three each

Item 202 - Regulated Underground Storage Tank Removed, two each

Item 202 - Removal Miscellaneous:  Scrap Tires,   Lump Sum

Typical Plan Note for: Asbestos Abatement

Environmental Work (MIA - 48 - 8.534, PID 12860)

Asbestos Abatement

An asbestos survey of the bridge structure scheduled for demolition was completed 6/99 by a certified asbestos hazard evaluation specialist (CAHES).  Approximately 440' of conduit, which contains asbestos materials, was identified on the bridge structure.  A copy of the Ohio Environmental Protection Agency Notification for Asbestos Demolition and Renovation Form with Sections I-VII, XVII, XVIII completed is available at the District 7 ODOT office (Planning Department).  The form must be submitted to OEPA-SWDO, DAPC (401 E. Fifth Street, Dayton, OH 45402) at least 10 days prior to demolition/renovation activities.

The Contractor shall take whatever precautions are possible to ensure that the asbestos containing material (ACM) does not become friable.  To ensure that the non-friable asbestos material does not become friable, or in the event that the non-friable material becomes friable, the Contractor shall provide an individual trained in the provisions of NESHAP that will be on-site during the demolition and/or removal of the ACM conduit.  All ACMs shall be properly containerized, transported, and disposed of in accordance with the state and federal regulations.

Basis of Payment

The Contractor shall furnish all the labor (including a CAHES), equipment, and materials necessary to complete, submit, and comply with the OEPA notification for and to remove, transport and dispose of asbestos containing materials in a licensed (by the local health department) and permitted (by the OEPA) solid waste facility.  Payment for this work shall be made at the contract prices bid Lump Sum.  The following quantity has been included in the General Summary for the work noted above:

690M98400 Item Special - Misc.:  Asbestos Abatement, Lump Sum

Typical Plan Note for: Removal and Disposal of Scrap Tires

Removal and Disposal of Scrap Tires (GRE - 42 - 14.25, PID 13134)

Scrap tires are located at approximately STA 23+660 to STA 23+720.  The Contractor shall be responsible for removing, transporting, and disposing of these scrap tires as per this plan note.

The Contractor shall ensure that the tires are removed and transported in a manner that satisfies all the appropriate OEPA regulations.  Specifically, the transportation of tires is governed by OAC 3745-27-56.  The disposal of tires shall be at a registered and permitted scrap tire facility as per OAC 3745-27-61 thru 65.

Basis of Payment

The Contractor shall furnish all the labor, equipment and materials necessary to remove, transport and dispose of scrap ties in a registered and permitted scrap tire facility.  Payment for this work shall be made at the contract price bid Lump Sum.  The following estimated quantity has been included in the General Summary for the work noted above:

Item 202 - Removal Miscellaneous:  Scrap Tires, Lump Sum

 Typical Plan Note for: Solid Waste and Regulated Water

ENVIRONMENTAL WORK (TRU - Belmont Avenue , PID 11910)   3/8/00

1.1 Introduction

The Ohio Department of Health has issued a Contact Advisory for the sediments of the Mahoning River for polycyclic aromatic hydrocarbons (PAH’s), polychlorinated biphenyls (PCB’s), Mirex (a pesticide) and phthalate esters.  Environmental studies conducted on sediments in the project area have shown that low levels of PAH’s and metals are present within the stream bed.  The Contractor shall manage all material required to be excavated from the river bed according to the following notes.  Estimated quantities have been included in the General Summary for this work.

1.2 Site Specific Health and Safety Plan (SSHSP)

The Contractor shall certify in writing to the Engineer within 2 weeks after contract execution and prior to any excavation that would disturb the sediment in the river bottom that the Contractor has prepared a SSHSP in accordance with 29 CFR Part 1910.120 for operations involving hazardous substances within the aforementioned limits.  The Contractor shall make the SSHSP available at the project site.  Copies of the environmental studies are available for examination in the Office of Contract Sales (Room 118) and the District 4 ODOT office (Planning Dept.).  This information may be used by the Contractor to develop the SSHSP. 

1.3 Material Handling and Disposal

The Engineer may permit temporary storage of the excavated material in a lined and covered roll-off box.  As an alternative, the Engineer may permit the Contractor to direct load the excavated material into trucks.

The Contractor shall properly transport and dispose of the excavated material in a licensed (by the local health department) and permitted (by the Ohio Environmental Protection Agency) solid waste facility.  If required by the solid waste facility, the Contractor shall be responsible for conducting sampling and analysis of the excavated material.

1.4 Potential Dewatering Of Excavated Areas

If the excavations in the aforementioned sediments require dewatering for construction purposes, the Contractor shall dewater, containerize, test, and subsequently dispose of waters by methods approved by the Engineer.  The Contractor shall obtain all the necessary permits and/or authorizations needed to store, test, transport and dispose of the water in accordance with applicable local, state, or federal regulations.

1.5 General Notes

All transport vehicles used for the movement of regulated sediments or water shall meet applicable local, state, and federal requirements.  The Contractor shall maintain records, such as manifests, landfill tickets, daily logs, etc., to document the source, movement, and destination of each truckload of contaminated sediments and/or water.  One copy of each of these records shall be submitted to the Engineer.

 1.6 Basis of Payment

The Contractor shall furnish all the labor, equipment, and materials necessary to properly develop and comply with a SSHSP, and handle, store, test, transport, and dispose of regulated materials, including any required permits, approvals, or fees within the limits identified above.  Payment for this work shall be made at the contract price bid per metric ton and cubic meters.

The following estimated quantity has been included in the General Summary for the work noted above:

Item Special - Work Involving Solid Waste, 50 MTON                         690M65010

Item Special - Work Involving Regulated Water, 5 CU M

                690M65024

Method of Measurement / Basis of Payment (202.13 and 202.14)

In general, when the Contractor must remove an item in order to perform other work, then there should be a separate pay item for the removal.  For example, when the contractor must saw cut sections of the pavement and curb and gutter in order to excavate and install a pipe, then there should be pay items for Pavement Removed and Curb and Gutter Removed.  In this example, there should also be pay items for the new pavement and curb and gutter.  However, if the Contractor damages the roadway, pavement, or other items due to his own negligence, then the Contractor must repair or replace the item at no expense to the Department.

Documentation Requirements - 202 Removal of Structures and Obstructions, and Regulated Waste Requirements

Regulated waste work may be inspected and documented by the District Environmental Coordinator, District Hazardous Waste Coordinator, or Regulated Waste Project Engineer.  When the inspection is required by these individuals it will be denoted below.

In addition, clearances or reviews need to be performed by other offices or individuals in the Department will be noted.  These are as follows, District Office of Production, Office of Geotechnical Engineering.

Obtain a copy of the waste agreement from approved landfill or the property owner whose land was used for the waste area.

1.        Structure Removed (lump sum):

a.        Statement on Inspector’s diary as to amount removed.

b.        State where material is disposed (waste agreement will be necessary).

2.        Pipe Removal:

a.        Cavity backfilled or in proposed excavation.

b.        Measure length and pipe diameter for pay.

c.        If pipe was abandoned how was it plugged?

d.        State how abandoned pipe was disposed.

3.        Pavement, Wearing Course, Sidewalk:

a.        Measure length and width for pay.

b.        Station and offset.

c.        State how removed and how material was disposed.

4.        Curb Removal:

a.        Measure length for pay.

b.        State how removed and how material was disposed.

5.        Guardrail Removal:

a.        Measure length for pay.  Holes backfilled or in proposed excavation.

6.        Catch Basin, Manholes, Inlets removed or abandoned:

a.        Inspector’s statement that work was performed.

b.        State what happened to existing conduits (abandoned and how plugged or hooked through).

c.        Backfill of cavity (if necessary) and material disposal.

7.        Buildings removed:

a.        Must have notice of possession and approval to proceed.

b.        Remove all tanks, foundations, basements, concrete slabs, and/or cisterns as outlined in 202.06.  Document how and where the material is disposed.

8.        Underground Storage Tanks:

a.        Remove in accordance with the “Bureau of Underground Storage Tank Regulations of the Division of Fire Marshal”; Ohio EPA; and applicable federal, state and local regulations.

9.        Septic tank and privy vaults:

a.        Empty tank and dispose material.

b.        Remove as outlined in 202.07.

10.     Raised Pavement Markers:

a.        Document location and quantity removed for disposal by Contractor.

b.        Fill voids before the end of the next working day.

Regulated Waste Requirements (DEC, DHWC or RWPE)

Responsibility

1.        Report all significant changes (Project).

2.        Health and safety requirements (DEC, DHWC, or RWPE).

Training

1.        Check training for the Project Engineers, Project Inspectors, and Consultant Inspectors.

2.        Check the medical monitoring needs.

3.        Check the training changes based on the health and safety plan.

4.        Keep training and medical records according to Sections 1105 and 1106 in the HWMPM.

a.        Regulated Waste Project Engineer gives these records to the District Environmental Coordinator for storage.

5.        Check all personnel for construction safety training.

Site Specific Health and Safety Plan

1.        Obtain a copy of the health and safety plan.

2.        Review of the health and safety plan.

3.        Obtain a new health and safety plan, if required.

Regulated Waste Designated for Removal in the Contract

1.        Review the contract requirements in the plan, proposal, or specifications.

2.        Perform the pre-excavation checks.

3.        Record the excavation operations and quantities.

4.        Record the type of temporary storage.

5.        Record the material sampling evaluation:

a.        Hazardous waste?

b.        Solid waste?

c.        Special waste?

d.        Non-regulated?

6.        Proper manifesting.

7.        Record the pre-transportation requirements and placarding.

8.        Keep disposal records:

a.        Regulated Project Engineer ensures these records are given to the District Environmental Coordinator for storage.

9.        Keep running lists of the weekly inspections.

Regulated Wastes Found during Construction

1.        Who and when was notified?

2.        Who was hired to evaluate the wastes?

3.        What tests were taken?

4.        What are the results?

5.        Perform the work as done in the previous section, “Regulated Waste Designated for Removal in the Contract”.

Other Wastes and Environmental Considerations

1.        Slag  (Project):

a.        Check environmental requirements in the specifications.

b.        Check the runoff from the materials after placement.

c.        Check the underdrain outlets for Tufa.

d.        Record the Tufa removal operations.

e.        Same as hazardous or solid wastes. (DEC, DHWC, or RWPE)

2.        Scrap Tires (Project):

a.        Document the removal.

b.        Requirements the same as solid waste (DEC, DHWC, or RWPE).

c.        DEC keeps the record for storage (DEC, DHWC, or RWPE).

3.        Rail Road Ties:

a.        Same as construction and demolition debris.

b.        Recycling is encouraged.

4.        Recycled Materials (Project):

a.        Ensure stability of the embankment (OGE).

b.        Check the Environmental Consultants Certification. (DEC, DHWC, or RWPE).

c.        Check the placement procedures in SS-871.

203 Roadway Excavation and Embankment

Introduction

After many years of solving soil and rock problems throughout the state, the author of this section can assure the reader of ‘One Constant.’

“Soil and Rock Conditions Vary, Vary and will Vary Again.”

The author could repeat this statement a hundred times throughout this manual and it would be a hundred times too few.

Earthwork consists of roadway excavations (cuts) and roadway embankments (fills) for highways and associated items of work.  Earthwork includes all types of materials excavated and placed in embankment, including soil, granular material, rock, shale, and random material.  Associated items of work, include preparation of foundations for embankment, disposal of excavated material, borrow, preparation of the subgrade, proof rolling, rock blasting, base construction, and berm aggregate construction.

If pavement is to remain smooth and stable during years of service under traffic, the earthwork on which it is built must be stable and must furnish uniform support.  Where roughness, settlements, and other distress develop in pavement during service under traffic, the cause often is a deficiency in the stability of earthwork that supports the pavement.

Uniformity of earthwork is necessary and important to obtain high stability and long-term performance at all locations throughout the length and width of the project.  Consider, for example, a highway project where 95 percent of the earthwork was performed according to the specifications, but five percent was non-specification and low-stability material, which appeared in many small areas throughout the project.  Pavement roughness and distress developed in these areas during service under traffic loading.  Such a project would be evaluated by the traveling public as a rough job or a poorly constructed project.  No notice or credit would be given to 95 percent of the work that was constructed properly.  The entire project might be discredited and be considered poor because a small proportion of the project was constructed with poor earthwork construction procedures or practices.

The foregoing example is intended to illustrate the need for consistent compliance with earthwork specifications in all areas, both large and small, throughout the length of the project, and from the beginning to the end of earthwork construction.

Importance of Proper Embankment Construction

The embankments that ODOT constructs are structures. The success of these structures is directly proportional to the project’s emphasis on correct embankment techniques.

The importance of proper construction practices cannot be overemphasized.  The results of improper construction practices may or may not show up during construction.  However, improper practices will eventually become evident at some point during the life of the embankment structure.

The construction requirements in the specifications are written to maximize the embankment structure’s life.  When the specifications are not followed, the life expectancy will decrease, and the future maintenance cost will increase.

The embankment structure is shown in Figure 203.A.  The structure consists of three main components:

1.        Foundation.

2.        Embankment.

3.        Pavement.

A geotechnical engineer ensures that the embankment will be stable as designed.  The pavement is constructed on top of the embankment.

Figure 203.A – Embankment Structure

The embankment that is shown in the plans structurally bridges the foundation and supports the pavement.  The embankment is built by compacting layers of materials in horizontal lifts, as shown in Figure 203.B.  These lifts consist of soil, granular material, rock, shale, asphalt, concrete, or recycled materials.  The embankment’s resistance to movement relies on the proper construction of these lifts. These lifts work together as a unit to resist the loads.

Figure 203.B – Embankment Layers

A condition, such as the one in Figure 203.C, can occur if an embankment is not properly constructed.  When this condition occurs, the factor of safety is less than 1.0 and the embankment fails.

Figure 203.C – Embankment Failure

A factor of safety is the ratio of the resisting forces divided by the driving forces, as shown in the following equation.

Typically the minimum factors of safety for embankment structures are from 1.3 to 1.5.  Figure 203.D illustrates the resisting and driving forces.  The weight of the fill works to move the foundation and the embankment counter clockwise to the right.  The internal strength of the embankment layers and the foundation work together to support the pavement.  Failure may occur in a circular fashion as shown, in a semi-circle, in a block mode, or wedge.  The basic principles are the same in all three modes of failure.

Figure 203.D – Resisting and Driving Forces for Embankment Failure

Importance of Proper Excavation

Proper excavation techniques in cut sections are just as important as embankment construction. The only difference is that when it fails, the rock or soil falls onto the roadway instead of the roadway failing.

This is illustrated in Figures 203.E-1 and 203.E-2.  If a soil cut is cut too steep, then the soil can flow onto the roadway as illustrated in 203.E-1.  This figure shows a deep-seated wedge failure.  This failure can also occur in an embankment condition.

Figure 203.E-1 – Cut Slope Failure (deep seated wedge)

Figure 203.E-2 – Cut Slope Failure (rotational failed condition)

Figure 203.E-2 details a rotational failed condition on the left.  The right side shows a design that is properly benching so that it reduces the driving forces.  If a rock cut is cut too steep, the rock can fall onto the roadway.

Figure 203.F – Falling Debris from Vertical or Nearly Vertical Faces near Roadway

The above rock and soil conditions can be avoided during the design or construction of a project.  Ensure that the plan intent is followed in these cut locations on the project.  Rock and shale excavations will be detailed under Section 208 Rock Blasting.

Materials (203.02)

In the 2002 version of the specification, the definitions and material requirements were changed for the different types of material allowed under the specifications.

In order to properly detail the requirements, it was necessary to divide up natural and recycled material requirements.  Too many times in the past Contractors would try to obtain approval for materials that were not intended under the specifications.

A natural material is a material that was created by nature; a material that is mined or excavated and graded is a natural material.  A material that is chemically altered by a manufacturing process such as concrete, fly ash, foundry sand, or slag is a recycled material.

Materials are defined in 203.02. All of the allowed materials are detailed in 203.02.R as “Suitable Materials.”  Specific, more detailed material requirements are located in 703.16.

In the following sections the materials will be detailed in the specific 203.02 sections for clarity.

If there is any doubt on the condition, status, acceptability, or approval of the materials throughout the following sections, then the project should contact one of the following:  the District Engineer of Tests, the District Geotechnical Engineer, the Aggregate Section of the Office of Materials Management, or the Office of Geotechnical Engineering.

Natural Soil (203.02.I)

The definition for natural materials in 203.02.I is as follows: “All natural earth materials, organic or inorganic, resulting from natural processes such as weathering, decay, and chemical action.”

Allowable materials are materials such as clay, silt, sand, or gravel.  These are allowed as suitable materials and are further defined in 703.16.A.

Department Group Classifications A-4-a, A-4-b, A-6-a, A-6-b, and A-7-6 are allowed. All of these materials are fine grained and have more than 35 percent of the particles passing the No. 200 sieve.  More detail can be found by examining Figure 203.G. These classifications are further defined on the right side of the chart under Silt-Clay Materials.

Materials must have a maximum dry density of at least 90 pounds per cubic foot (1450 kg/m³).  Materials that are less than this density usually have too much organic matter or clay materials. 

Soils that have a liquid limit in excess of 65 or identified as Department Group Classifications A-5, or A-7-5 are not allowed.  The A-5 material is highly elastic by virtue of its high liquid limit. The A-7-5 material is highly elastic and subject to volume change.

Natural Granular Materials (203.02.H)

These materials are defined in 203.03.H as follows: “Natural granular materials include broken or crushed rock, gravel, sand, durable siltstone, and durable sandstone that can be placed in an 8 inch (200 mm) loose lift.”

These materials are allowed in 203.02.R, Suitable Materials. The material requirements are further detailed in 703.16.B and 703.16.C.

Under 703.16.B, Department Group Classifications A-1-a, A-1-b, A-3, A-3-a, A-2-4, A-2-6, or A-2-7 are allowed.  All of these materials generally are mixtures of coarse and fine grained materials.  These materials have less than 35 percent of the particles passing the No. 200 sieve.  More detail can be found by examining Figure 203.G. These classifications are further defined on the left side of the chart under Granular Materials.

Granular material classified as A-2-5 is not allowed because of its low weight, high optimum moisture, high LL, low PI, and its propensity to slough.

Section 703.16.C allows durable sandstone and durable siltstone.  If these materials meet the slake durability requirements in ASTM D 4644, then the material is considered equivalent in strength and durability to other natural granular materials.

Section 703.16.C allows slags and recycled Portland cement concrete to be used as granular material types.

Contact the Office of Geotechnical Engineering to arrange for the appropriate materials testing if sandstone or siltstone is used for this application.

Figure 203.G – Department Soils Classification Chart

Identifying Soil and Granular Materials in the Field

It is sometimes necessary to make field decisions based on very little (if any) laboratory soils information.  It may be necessary to verify the accuracy of plan soil borings in the field.  In these two cases, and on other occasions, it is important to have a basic understanding of how to identify types of soils and granular materials in the field.  The following are some, but certainly not all, of the methods that can be used to identify these materials in the field.

Granular Soils

Granular soils are easily identified by their particle size in the field.  A sample may be taken inside and spread on a table to dry.  A rough estimate of the material retained or passing each sieve may be obtained by examining the material when dry. Finer materials such as clays and silts cannot be separated and can only be distinguished between one another by a settling technique.  This can be accomplished by using a hydrometer or by performing a crude settling test.  This technique is beyond the scope of this manual.

Fine Grained Soils (Clays and Silts)

It is more important, yet harder to distinguish between a clay and silt material in the field.  Clays and silts should be treated and used differently in the field because of their difference in engineering and compaction properties.  Refer to properties of soils in the next section.

A clay material can be easily rolled into a thread at a moisture content near, or above, the plastic limit of the material.  Clays can often be rolled into 1/8 inch (3 mm) diameter threads (about half the diameter of a pencil).  See the plastic limit test later in this manual for further information.  As the clay content increases, the thread may be easier to roll into smaller sizes.  No matter what the soil content is you cannot roll a pure silt material into a 1/4 inch (6 mm) thread.

Clay forms hard pieces that cannot be broken by hand pressure when it is dry.  Place an irregular piece of dry soil between the index finger and the thumb, and try to break the material.  If the material is difficult or impossible to break, it is probably clay.  A silt or sandy material will generally break easily with this amount of hand pressure.

Clay fines are generally greasy, soapy, and sticky.  Wet clay dries much slower than silt.

When performing these hand techniques, observe the soil residue found on your hands for further information.  If the soil on your hands is difficult to remove, and the hands need to be rubbed briskly together to remove the soil, the material is probably clay.  A silt material is easily removed when hands are rubbed together.

A silt material will react to vibration or shaking.  Place a small amount of pliable soil in your hand.  Hold the material in one hand and drop that hand on the other hand or a hard surface.  Water will form on the surface of a silt material.  You can also put the soil in a bowl and tap it on a table to get the same result.  Clay will not react to this test.

The aforementioned identification techniques should not replace classification by the laboratory, but should be used as a supplement.

If there is any concern, send a sample to the District Engineer of Tests for further classification.

Engineering Properties of Soil and Granular Materials

The following are general statements regarding the engineering properties of soil and granular materials.  Consider these properties when solving field problems.

Properties of Granular Soils

1.        Good foundation and embankment material.

2.        Not frost susceptible, if free draining.

3.        May erode on embankment side slopes.

4.        Identified by the particle size.

5.        Easily compacted when well graded.

Properties of Fine Grained Soils

1.        Often have low strengths.

2.        Plastic and compressible.

3.        Lose part of their shear strength when wet or if disturbed.

4.        Practically impervious.

5.        Slopes are prone to slides.

 Properties of Silts

1.        High capillary action and frost susceptible.

2.        No cohesion and non-plastic when pure silt.

3.        Highly erodible.

4.        Difficult to compact.

5.        Release water readily when vibrated.

6.        Acts like an extremely fine sand during compaction.

Properties of Clay as They Relate to Silt

1.        Better load-carrying qualities.

2.        Less permeable than silt.

3.        Easier to compact than silt. (Any soil is easier to compact than silt.)

4.        More volume change potential.

5.        Plastic or putty-like property.

6.        Clays are weaker when compacted wet of optimum.

Moisture Effects on Soils

Granular soils are less affected by moisture content than clays and silts; have larger voids; and are free draining.  Granular materials have relatively larger particles than silts and clays.

Moisture content (also called water content) has a large effect on the physical properties of fine-grained soils.  The Atterberg Limits are used to describe the effect of varying moisture contents on the consistency of fine-grained soils.  See Figure 203.H.

Figure 203.H – Atterberg Limits

The plasticity index (PI) is used to classify soils.  The plasticity index is calculated by subtracting the plastic limit (PL) from the liquid limit (LL) (e.g. PI = LL – PL).  The liquid limit and plastic limit are the moisture contents at the condition of the test.

Liquid Limit

1.        Transition between the plastic solid and liquid state.

2.        At liquid limit of 100 the soil contains equal weights of soil and water (i.e., Wc = Ww/Ws = 50/50).

3.        At liquid limit of 50, the soil is 2/3 soil and 1/3 water (example Wc = 33/66).

4.        High liquid limit indicates soils of high clay content and low load carrying capacity.

Plastic Limit

1.        Transition between semi-solid and the plastic solid.

2.        The soil condition, when it contains just enough moisture to be rolled into a 1/8-inch diameter thread without breaking, just starts to break-up.

3.        Governed by the clay content.

4.        The greater the clay content, the higher the plasticity (PI = LL – PL) and cohesiveness.

5.        Load carrying capacity increases rapidly as the moisture content decreases below the plastic limit.

The following is a brief description of the characteristics of soils in the physical states.

Liquid Soil State Characteristics

1.        Highly saturated state.

2.        Flows under its own weight.

3.        Very little or no friction between the particles.

Plastic State Characteristic

1.        Soil can be remolded into various shapes.

2.        Like modeling clay.

Semi-Solid Soil State Characteristics

1.        No longer pliable.

2.        Sample will crumble when rolled.

Brittle Solid Soil Characteristics

1.        Soil ceases to change volume due to the loss of water.

2.        No real engineering application.

Detailed Soil Property Explanation

Each term used in geotechnical engineering has specific meaning and application.  Each soil test has specific meaning and application and indicates certain soil properties.  Using correct terminology will prevent confusion and misunderstanding.

Soil

Soils have properties that influence their behavior and value.  The properties of soil will vary with gradation (composition), moisture content, vertical position in relation to the surface of the ground, and geographical location.  The more common properties encountered and used in highway work are defined and discussed in Section 203.

Most soils were originally solid rock. Time and climate have broken the rock into progressively smaller particles.  This can be shown in the laboratory by taking two or three pieces of gravel or stone and pulverizing them.  First, sand-sized particles can be made, then silt-sized particles, and finally clay-sized particles. Chemical changes take place as nature reduces rock into finer particles; therefore, clay produced by nature over a period of many years will vary from clay-sized material produced in a short time in a laboratory.

Particle Size

By naming and defining the size of soil particles, all soil tests are placed on a common ground for comparison.  The amount of soil retained or passing each sieve is one of the major tools used to judge, analyze, and classify soil.

The quantities of each are determined by a laboratory analysis that separates the soil into groups of particle sizes.  The standard methods of test prescribed by AASHTO T-88 and ASTM D-422 have been used widely in highway engineering and are used by the Department.

The distribution of particle sizes larger than 0.074 mm retained on the No. 200 (75 μm) sieve is determined by sieving, while the distribution of particle sizes smaller than 75 μm is determined by a sedimentation process, which uses a hydrometer to determine the necessary data.

Size definitions used by the Department are the same as definitions used by AASHTO T-88 with the exception of clay:

Component

Size

Boulders

Larger than 12 inches (300 mm)

Cobbles

3 to 12 inches (75 to 300 mm)

Gravel

Coarse

¾ to 3 inches (19 to 75 mm)

Fine

#10 sieve to ¾ inch (2 to 19 mm)

Sand

Coarse

#40 sieve to #10 sieve (0.42 to 2.0 mm)

Fine

#200 sieve to #40 sieve (0.074 to 0.42 mm)

Silt

0.005 to 0.074 mm

Clay

Smaller than 0.005 mm

Texture

The amount of each soil type (i.e., boulders, cobbles, silt, and clay) contained in a soil mixture determines its texture or feel.  Soil classifications by texture must not be confused with soil classifications for engineering purposes.  Sometimes these classifications are similar, but other times they may be different.  The amount of each soil type in a soil mixture is determined by laboratory tests.  The test results are then compared with texture definitions in order to determine texture name.

Soil texture is classified after its sieve size is determined.  It is possible to make approximations of texture by the feel of moist soil when rubbed and ribboned between the thumb and index finger.

The texture of soil tells a lot about the soil.  Using texture classification, approximations and estimations can be made of soil properties, such as bearing value, water-holding capacity, probability to frost heave, permeability, etc.

Soil Components (Major and Secondary)

It is the practice of the Department to describe soil components and texture of a soil as follows:

Major Components

Major components are described as gravel, sandy gravel, gravelly sand, sand, silty sand, clayey sand, sandy silt, silt, clayey silt, silty clay or clay.  More than 35 percent of the total sample is required in order to classify a major component.  Where two words are used to describe the major component, the second word describes the greater quantity.

Examples:  Sand predominates in silty sand while silt predominates in sandy silt.

Secondary Components

Descriptions of secondary components are preceded by the term listed below, according to the percent of total sample indicated:

Term

Percent of Total Sample

Trace

0 to 10

Little

10 to 20

Some

20 to 35

And

35 to 50

Examples of material texture descriptions based on component test results are as follows:

Material Components

Texture Description

Sand 30%, silt 55%, clay 15%

“sandy silt with little clay”

Sand 8%, silt 55%, clay 37%

“silt and clay with trace sand”

Gravel 20%, sand 68%, silt 12%

“gravelly sand with little silt”

Gravel 2%, sand 12%, silt 42%, clay 38%

“silt and clay with little sand, trace gravel”

Internal Friction

Internal friction is defined as the resistance to sliding within the soil mass.  Gravel and sand impart high internal friction and the internal friction of a soil increases with sand and gravel content.  For sand, the internal friction is dependent upon the gradation, density, and shape of the soil particle, and is relatively independent of the moisture content.  Clay has a low internal friction, which varies with the moisture content.  A powder-dry, pulverized clay has a much higher internal friction than the same soil saturated with moisture since each soil particle can slide on adjoining soil particles much more easily after it is lubricated with water.

Various laboratory tests have been devised to measure internal friction.  It is defined as the angle whose tangent is the ratio between the resistance offered to sliding along any plane in the soil and the component of the applied force acting normal (perpendicular) to the plane.  Values are given in degrees.  Internal friction values range from 0 degrees for clay, just below the liquid limit, to as high as 34 degrees or more for a dry sand.  Very stiff clay may have a value of 12 degrees.

The governing test should be based on the most unfavorable moisture conditions that will prevail when the soil is in service.  This “angle of internal friction” is not the same as the natural angle of repose or degree of slope on the soil in fills.

Cohesion

Cohesion is defined as the mutual attraction of particles due to molecular forces and the presence of water.  The cohesive force in a soil varies with its moisture content.  Cohesion is very high in clay but of little or no significance in silt and sand.  Powder-dry, pulverized clay has low cohesion.  However, as the moisture content is increased, the cohesion increases until the plastic limit is reached.  The addition of more moisture reduces the cohesion.  By partially over-drying wet clay, most free water is removed and the remaining moisture will hold the clay particles firmly together. This will give the soil such high cohesion that a hammer may be required to break the particles apart.  These conditions are illustrated by the dry dirt road in summer that dusts easily, but carries large loads; the muddy, slippery road of spring and fall; and the hard-baked surface of a road immediately after summer rains.

Various laboratory tests have been devised to measure cohesion.  Results are usually given in pounds per square foot (psf) or kilopascals (kPa) and may vary from 0 psf in dry sand and wet silt to 2,000 psf (96 kPa) in very stiff clays.  Very soft clays may have a value of 200 psf (10 kPa).  The governing test should be based on the most unfavorable moisture condition that will prevail during service.

Internal Friction and Cohesion

The stability and the structural properties of soil are determined largely by the combined effects of internal friction and cohesion.  In most soils these combine to make up the shearing resistance.  The combined effects are influenced by other basic factors, such as capillary properties, elasticity, and compressibility.

All of these factors, plus the site on which the soil is located, determine the moisture content that will prevail in the soil in service.  They also govern the load-carrying capacity of a soil, which is the primary concern.  The clay-gravel road made up largely of gravel and sand, with a small amount of silt to fill voids, and a small amount of clay to give cohesion, illustrates a soil of high bearing value. This soil is produced by high internal friction due to sand and gravel and high cohesion due to clay.  Clay illustrates a soil of low bearing value. When clay is wet, internal friction is negligible since no coarse grains are present, and cohesion is low since it has been destroyed by moisture.  The same clay, air-dry, will have high bearing value due to high cohesion brought about by the removal of moisture.

Capillarity

Capillarity is defined as the action by which a liquid (water) rises in a channel above the horizontal plane of free water.  The number and size of the channels in a soil determine its capillarity.  This soil property is measured as the distance moisture rises above the water table and will range from 0 in some sand and gravel to as high as 30 feet (9 meters) or more in some clay soils.  It often requires a long period of time for water to rise to the maximum possible distance in clay soils because the channels are very small and frequently interrupted, and the frictional resistance to water is great in the tiny pores.

Moisture in silt soils may be raised by capillarity only 4 feet (1 meter) or so.  Since the capillary pores are larger than for clay, a larger quantity of water is raised in a few days rather than over a long period.  Silts are considered to have “high capillarity” by geotechnical engineers because of this rapid rise of water.  The capillary rise in gravels and coarse sands varies from zero to a maximum of a few inches.

Complete saturation of soil seldom occurs at the upper limits of rise in capillary moisture. Capillarity of a soil and the elevation of the water table under the pavement determine whether the subgrade will become saturated in this manner.  Whether or not the subgrade becomes saturated from capillary action, or from condensation, seepage, etc., determines the bearing value of the soil to a considerable extent.  Subgrade saturation by capillarity determines whether frost heave and similar occurrences in subgrade will create a problem requiring treatment for satisfactory performance in service.

Compressibility and Elasticity

Compressibility and elasticity are the properties of a soil that cause it to compress under load or compaction effort and to rebound or remain compressed after compaction.  Most soils are compressible.  Silty soils of the A-5 group are the most elastic of Ohio soils and make poor subgrades for pavements.  Fortunately, A-5 soils are limited in occurrence in Ohio.  The A-7 soils in Ohio are moderately elastic, but do not present special problems in embankment or subgrade.  A-4 soils are elastic under some moisture conditions, and sometimes present problems of stability during construction, but provide adequate support for pavements where good design and construction practices have been followed.

Soil elasticity measurement is determined by special tests that simulate moisture changes and loading conditions anticipated in the field.

Elasticity and Deformation of Soils

When heavy rubber-tire construction equipment moves over an embankment layer foundation of wet, fine-grained soil, some movement of the embankment surface occurs.  Elastic movement occurs when a tire moves onto an area, the surface is deformed, and when the tire moves off the area, the surface rebounds, or springs back, with little or no permanent rutting of the surface.  Cracking of the surface may or may not occur following this type of movement.

Cracking may occur in cases of pronounced elasticity.  In the case of pronounced elasticity or deformation, there is displacement of surface soil to each side of the tire, which results in deformation, rupture, cracking, and rutting.

The magnitude of the elastic movement or deformation may depend on one or more factors:

1.        Weight of equipment.

2.        Size of tires.

3.        Tire pressure.

4.        Soil moisture.

5.        Type of soil.

6.        Depth of soil layer.

7.        Stability of material underlying the soil layer being observed.

Some embankment elasticity and deformation is expected under construction equipment loading.  Moderate movement of less than a 1/2 inch (13 mm) can occur with heavy equipment weighing around 35 tons on embankments of satisfactory stability.  This moderate movement is not considered detrimental.  Greater movement is likely on adequately stable embankments under very heavy equipment weighing greater than 35 tons.  Except for specialized situations, such as soft foundation soil at shallow embankment depth, under the layer being observed, the greater movement due to these very heavy loads is not detrimental.  In general, elastic or deformation movement under heavy or very heavy loads should be permitted if the moisture of the embankment is at least 2 percent below optimum.

Moisture control specifications are not intended to limit or restrict the use of very heavy construction equipment on embankment construction.  The intent of the specifications is to limit the moisture to obtain a stable embankment.

The amount of elasticity and permissible deformation under any given load varies with job circumstances.  For example, for the first layer over a soft, original ground embankment foundation, considerable movement under loaded construction equipment is inevitable due to the soft foundation material.  The resistance to deformation is more critical in the top portion of embankment, near the subgrade, than in lower portions of the embankment.  If the lower embankment layers are low-stability material, such as wet silt, elasticity and deformation of the lower embankment layer must be closely monitored.  This would not be necessary if successive embankment layers were made of high stability material, such as rock, shale, granular material, or dry soil.

Equipment which can be used successfully to test for embankment stability includes rubber-tired roller, grader, loaded scraper, or loaded truck.  More movement is to be expected under very heavy equipment than under heavy equipment ordinarily used in highway work.  When rubber-tire construction equipment, such as scrapers, graders, or rollers are being used over the entire general area during normal embankment construction operations, and observation shows no area of questionable stability; it is not necessary to have a piece of testing equipment systematically cover the entire area to observe stability.

When the Engineer or Inspector questions or desires to check the stability of an area during embankment construction, they are authorized to require that the Contractor moves suitable equipment over the area to check for pronounced elasticity or deformation.

The determination of pronounced elasticity or deformation under the action of loaded rubber-tire construction equipment is based on the description given in the second paragraph of this section.

The administration of this requirement should be tempered with sound judgment backed by construction experience.

Shrinkage

Shrinkage refers to the apparent decrease in volume of a soil during its removal from the cut or borrow and its placement in the embankment.  Shrinkage is caused by a greater density in the fill than in the cut or borrow area.  Shrinkage is not accounted for nor contemplated in the design of the project.

The amount of shrinkage resulting from increased density in the embankment material may be estimated by using a volume or dry density basis.

Either one of the following equations can be used to calculate the Shrinkage Factor (SF).

Example of the use of a shrinkage factor:

The adjustment due to shrinkage is only used where the material is measured in a borrow pit and the embankment is placed outside of the plan allowed tolerances.  Due to specification and design changes, the use of borrow as a pay item should be minimized in the future.

Settlement and Scalping Losses

Losses due to scalping are usually insignificant as a percentage of the overall embankment construction quantities.  Scalping losses of around 6 inches from the original cross-sections can be expected during construction. This is not compensated by the Department.  If there is significant losses beyond this, it can be accounted for by taking cross-sections and then compensation should be made.

Settlement of the embankment foundation can be an area where the contractor can lose material that is not measured directly.  It can be accounted for in the earthwork quantity calculations.

Losses due to settlement of the embankment foundation, where the foundation is compressible, can be calculated by using settlement platforms.  A settlement platform, or several platforms, can be placed on the foundation.  The platform is measured throughout the life of the embankment construction.  A settlement verses time curve can be used to determine the amount of additional payment that is due.  See Figure 203.I.

Figure 203.I – Settlement Curve

The amount of settlement that occurred over the life of the embankment construction is a function of this Total Settlement Curve.  To make the additional embankment payment, multiply the settled amount by the length and width of the settled area.  This length and width should be calculated at the half height of the embankment in the affected area.  Some judgment is required regarding the length of influence of individual or multiple settlement platforms. 

Example of total settlement:

543.11 - 542.88 = 0.23 feet

Permeability

Permeability is a property of soil that allows it to transmit water. It is defined as the rate at which water is transmitted by soils.  Permeability depends on the size and number of soil pores as well as the difference in height of water at the point where it enters the soil and the point where it emerges.  It is determined by tests on a representative soil sample and expressed as the coefficient of permeability, and it equals the velocity of water-flow in centimeters per second (cm/sec) under a hydraulic gradient of 1.  A hydraulic gradient of 1 exists when the pressure head (or height of water) on the specimen in centimeters divided by the depth of the specimen in centimeters equals 1.

The permeability of a soil varies with factors such as void ratio, particle size and distribution, structure, and degree of saturation.  The permeability of a particular soil will vary with the degree of compaction since this will influence the size of soil pores.  A particular soil, loosely packed, will be more permeable then the same soil tightly packed.  Nature produces these differences along with shrinkage forces that may be present by surface freezing in winter (loosening a soil) and by repeated wetting and drying in the summer (consolidating the soil).

The coefficient of permeability, k, is used to determine the quantity of water that will seep through a given time and distance under a known head of water.  It is calculated using the following equation.

The equation can be rearranged to find the quantity of seepage, Q, as shown below.

Q     =      Quantity of water, in cubic centimeters (cm³)

k      =      Coefficient of permeability, in centimeters per second (cm/sec)

H     =      Hydrostatic head, in centimeters

L      =      Thickness of soil, in centimeters, through which flow of water is determined under hydrostatic head H;

A     =      Cross-sectional area of material, in square centimeters (cm²);

t       =      Time, in seconds (sec).

Tile can drain very porous soils, such as sands that have a k of 1.0 to 10-3 (0.001) cm/sec.  Silty and clayey sand soils have a k of about 10⁻³ (0.001) to 10⁻⁷ (0.0000001) cm/sec.  Highly cohesive clays have a k of less than 10⁻⁸ (0.00000001) cm/sec.  It is difficult, if not impossible, to reduce the water content of soils by tile drains when the permeability coefficient is less than 10⁻³ (0.001).  For earth dams, the U.S. Bureau of Reclamation classifies soil with k values approximately 10⁻⁴ (0.0001) as pervious and soil with k below 10⁻⁶ (0.000001) as impervious.

Soil Group classifications A-6a, A6b and A-7-6 are generally considered impervious.

Plastic Limit

The plastic limit (PL) of soils is the moisture content at which a soil changes from a semisolid to a plastic state.  This condition is said to prevail when the soil contains just enough moisture that it can be rolled into 1/8 inch (3.18 mm) diameter threads without breaking.  The test, ASTM D-424 or AASHTO T-90, is conducted by trial and error, starting with a soil sufficiently moist to roll into threads 1/8 inch (3.18 mm) in diameter.  The moisture content of the soil is reduced by alternating manipulation and rolling until the thread crumbles.

Clay content controls the plastic limit.  Some silt and sand soils cannot be rolled into 1/8-inch (3.18 mm) threads at any moisture content; these have no plastic limit and are termed non-plastic.  The test is of no value judging the relative load-carrying capacity of non-plastic soils.

A very important change in load-carrying capacity of soils occurs at the plastic limit.  Load-carrying capacity increases very rapidly as the moisture content is decreased below the plastic limit.  On the other hand, load carrying capacity decreases very rapidly as the moisture content is increased above the plastic limit.

Liquid Limit

The liquid limit (LL) is the moisture content at which a soil passes from a plastic to a liquid state.  The test, ASTM D-423 or AASHTO T-89, is performed by determining, for various moisture contents, the number of blows of the standard cup needed to bring the bottom of the groove into contact for a distance of more than 1/2-inch (12.7 mm).  These data points are then plotted and the moisture content at which the plotted line (called flow curve) crosses the 25 blow line is the liquid limit.

Sandy soils have low liquid limits of the order of 20.  In these soils the test is of little or no significance in judging load-carrying capacity.

Silts and clays have significant liquid limits that may run as high as 80 or 100.  Most types of clay in Ohio have liquid limits between 40 and 60.

High liquid limits indicate soils of high clay content and low load-carrying capacity.

Liquid limit can be used to illustrate the interpretation of moisture content as a percentage of the oven-dry weight of the soil.  See an example in the previous section on liquid limit.

Plasticity Index

The plasticity index (PI) is defined as the numerical difference between liquid limit and plastic limit.  Calculation details are included in ASTM D-424 and AASHTO T-90.  The plasticity index gives the range in moisture contents at which a soil is in a plastic condition.  A small plasticity index, such as 5, shows that a small change in moisture content will change the soil from a semisolid to a liquid condition.  Such a soil is very sensitive to moisture unless the combined silt and clay content is less than 20 percent.  A large plasticity index, such as 20, shows that considerable water can be added to the soil before it changes from a semisolid to a liquid.

When the liquid or plastic limit cannot be determined, or when the plastic limit is equal to or higher than the liquid limit, the plasticity index is considered non-plastic (NP).

The moisture conditions at the plastic limit and liquid limit, and the plasticity index, often are called the “Atterberg Limits” (named after Albert Atterberg, the Swedish agricultural scientist who developed the concept).

Detailed Description of the Soil Classification Groups

The following is a brief description of the materials in each classification group detailed in Figure 203.G.

Group A-1

The typical material of this group is a well-graded mixture of gravel stone fragments, coarse sand, fine sand, and a non-plastic or feebly plastic soil binder.  However, this group may also include the same material without the soil binder.

Subgroup A-1a

This material predominantly consists of stone fragments or gravel, either with or without a well-graded soil binder.

Subgroup A-1b

This material predominantly consists of coarse sand with or without a well-graded soil binder.

Group A-3

The typical material of this group is fine beach sand without silty or clay fines or with a very small amount of non-plastic silt.  The group also includes stream-deposited mixtures of poorly-graded fine sand and limited amounts of coarse sand and gravel.  These soils are sometimes difficult to compact, similar to the A-4 group.  The fineness of the material and the silt fines make stabilization difficult.  See the group A-4 for further explanation.

Subgroup A-3a

This material consists of mixtures of coarse and fine sand with limited amounts of low plasticity silt.

Group A-2

This material consists of a wide variety of granular materials which borderline between Groups A-1 and A-3 and the silt-clay materials of Groups A-4, A-5, A-6 and A-7.  It includes all materials containing 35 percent or less passing the No. 200 (75 μm) sieve which cannot be classified as A-1, A-3 or A-3a, due to fines content or plasticity (or both) in excess of the limitations for those groups.

Subgroups A-2-4 and A-2-5

This material consists of various granular materials containing 35 percent or less passing the No. 200 (75 μm) sieve and with a negative No. 40 (425 μm) portion which have the characteristics of the A-4 and A-5 groups.

This material consists of materials such as gravel and coarse sand with silt contents of plasticity indexes in excess of the limitations of Group A-1, and fine sand with non-plastic silt content in excess of the limitations of Group A-3.  A-2-5 soils are unsuitable embankment material under 703.16.B because of its low weight, high optimum moisture, high LL, low PI, and its propensity to sloughing in service.

Subgroups A-2-6 and A-2-7

This material consists of materials similar to those described under Subgroups A-2-4 and A-2-5 except that the fine portion contains plastic clay which has the characteristics of the A-6 or A-7 group.  The approximate combined effects of plasticity indexes in excess of 10, and percentages passing the No. 200 (75 μm) sieve in excess of 15, are reflected by group index values of 0 to 4.

Group A-4

The typical material of this group is a non-plastic, or moderately plastic, silty soil usually having 75 percent or more passing No. 200 (75 μm) sieve.  This group also includes mixtures of fine, silty soil and up to 64 percent of sand and gravel retained on No. 200 (75 μm) sieve.  The group index values range from 1 to 8, with increasing percentages of coarse material being reflected by decreasing group index values.  The A-4 group soils are usually very difficult to compact or stabilize.  Minimizing the water content to obtain the required density and stability usually works.  It is not unusual, nor is it a change in condition, to have difficulty in stabilizing or compacting these soils.  This condition should be expected for this type of material.

Subgroup A-4a and A-4b

Subgroup A-4a contains less than 50 percent silt sizes.  Subgroup A-4b contains more than 50 percent silt sizes.  A-4b is only allowed 3.0 feet (1.0 m) below subgrade elevation because of frost heave potential.  Both are susceptible to erosion.

Group A-5

The typical material of this group is similar to that described under Group A-4, except that it may be highly elastic as indicated by the high liquid limit.  The group index values range from 1 to 12, with increasing values indicating the combined effect of increasing liquid limits and decreasing percentages of coarse material.  This soil is unsuitable under 703.16.A for use as embankment material because of its elasticity.

Group A-6

The typical material of this group is a plastic clay soil which has 75 percent or more passing the No. 200 (75 μm) sieve.  The group includes mixtures of fine clayey soil and up to 64 percent of sand and gravel retained on the No. 200 (75 μm) sieve.  Materials of this group usually have high volume changes between wet and dry states.  The group index values range from 1 to 16, with increasing values indicating the combined effect of increasing plasticity indexes and decreasing percentages of coarse material.

Subgroup A-6a and A-6b

Subgroup A-6a contains material with plasticity index of 15 or less.  Subgroup A-6b contains material with a minimum plasticity index of 16.

Group A-7

The typical material of this group is similar to that described under Group A-6, except that it has the high liquid limit characteristics similar to that of group A-5, and may be elastic as well as subject to high volume change.  The range of group index values is 1 to 20, with increasing values that indicate the combined effect of increasing liquid limits and plasticity indexes and decreasing percentages of coarse material.

Subgroup A-7-5

Includes those materials with moderate plasticity indexes in relation to liquid limit and may be highly elastic as well as subject to considerable volume change.  This soil is unsuitable under 703.16.A because of its elasticity.

Subgroup A-7-6

Includes those materials with high plasticity indexes in relation to liquid limit and are subject to extremely high volume change.

Slag Materials (203.02.Q)

Slags are by-products from manufacturing steel or iron.  Under 203.02.Q, Air-Cooled Blast Furnace slag (ACBF), Granulated slag (GS), Open Hearth (OH) slag, Basic Oxygen Furnace (BOF) slag, and Electric Arc Furnace (EAF) slag that meet the requirements in 703.16 are allowed under Item 203.

Air Cooled Blast Furnace Slag

Air Cooled Blast Furnace slag is a by-product from making iron.  It is a very hard and durable aggregate, which contains visible holes.  ACBF slag may have a maximum dry density of approximately 80 lbs/ft³ (1280 kg/m³) and is lighter than most soils.

ACBF slag can produce a green, yellow, white, or black runoff; the color is usually pH driven.  This runoff can smell like rotten eggs and usually goes away in 6 months, but not always.  The runoff may exceed the allowable limits under the Clean Water Act.

The potential for the runoff to exceed the Clean Water Act is based on the following factors:

1.        The contaminate concentration of the ACBF slag.

2.        The permeability of the ACBF slag.

3.        The geometry of the in-place system.  ACBF slag next to an underdrain has a higher potential than ACBF slag located in a fill surrounded by clay.

4.        The amount of water flowing through the system.

5.        Time of contact with the slag.  Stagnant water around slag increases the potential for problems.

To minimize this problem in embankment construction, ACBF slag must pass the Sulfur Leachate Test described in Supplemental Specification 1027.  The manufacturers are required to certify that their material meets this requirement.  Contact the District Testing Engineer or the Aggregate Section of the Office of Materials Management to verify that the material may be used.

Further details about the potential problems can be found in Other Wastes and Environmental Considerations in Section 202, Regulated Waste Requirements, of this manual.

Granulated Slag

Granulated Slag (GS) is a by-product of making iron or steel.  GS is a slag that has been quenched with water during the cooling process instead of air-cooling.  Most of the granulated slags are iron slags.  If steel slags are quenched with water they may cause explosions.  Steel slag has about 20 to 25 percent iron in the slag, while iron slag has less than 1 percent.  It is a very light and brittle material, almost like powder in the pre-compaction condition.  After compaction, it is very hard, durable, and almost impermeable.  This material sets up like concrete in service.  The maximum dry density can range from 50 to 90 lbs/ft³.

Steel Slags

Steel slags are by-products of making steel.  There are three kinds of steel slag defined in 203.02.Q: OH slag, BOF slag, and EAF slag.  OH slag is the slag that was produced mainly pre-1970; however, some OH slag was made in the 1970’s.  BOF and EAF slags are newer and faster processes for making steel; however, some BOF plants were in operation in the late 1950’s.

The problems associated with steel slags are worse for EAF and BOF slags than for OH slag.  The process for making OH slag is slower than the other two materials.  This slower process allows more of the harmful chemicals to be burnt out of the OH slag.  Consequently, OH slag is a better product for embankment applications.

Some steel slags can expand, clog up underdrains, or have a high pH runoff.  The specifications were written to minimize these problems.  Similar to ACBF slag, the following factors were considered when writing the specification requirements:

1.        The contaminate concentration (mainly MgO and CaO) of the steel slag.

2.        The permeability of the steel slag.

3.        The geometry of the in place system.

4.        The amount of water flowing through the system.

5.        Time of contact with the slag.  Stagnant water around slag increases the potential for problems.

6.        The load or weight on the material.

Further details can be found in Other Wastes and Environmental Considerations in Section 202 Regulated Waste Requirements. OH, BOF, and EAF slags may be used in embankment construction if the materials comply with Section 703.16.

Section 703.16 requires that OH, EAF, and BOF slag be blended with natural soil or natural granular material.  For OH slag, the blend must be at least 30 percent natural soil or natural granular materials.  For BOF or EAF slags, the blend must be at least 50 percent natural soil or natural granular material.

The OH, EAF, and BOF slag must also comply with Section 703.15, which states that the aging, stockpiling, deleterious substances, and crushing requirements of 703.14 apply.

OH, EAF, and BOF slag and blends are further restricted in 203.03.E and 203.03.F. These materials must be at least 1 foot (0.3 m) below the underdrains to minimize underdrain clogging. These materials cannot be used underwater because of the potential pH problems.

All of the above restrictions minimize the factors that can lead to expansion, clogged underdrains, or high pH runoff problems.

Granular Embankment Material Types (703.16.C)

These materials replace the old granular embankment requirements under the 1997 specification book.  The old requirements were too loose, and just about any material could pass as granular material, even though it may not fit the engineering or designed need in the plans.

In 703.16.C, the following kinds of material are allowed: limestone (crushed carbonate stone or CCS), gravel, ACBF slag, durable sandstone, durable siltstone, GS, or blended natural soil or granular materials with OH, BOF, EAF, or RPCC.

Durability requirements for sandstone and siltstone were previously covered in this manual under Natural Granular Materials 203.02.H.  The slag requirements were previously covered in, Slag Materials 203.02.Q, of this manual.  RPCC will be covered later in this manual and must be blended similar to the slags.  GS was previously covered and is not required to have a specific gradation.

Six different gradations, or types, are available for use in construction. Below is a general description of these materials:

1.        Type A Granular Material has less than 25 percent passing the No. 200 (75 µm) sieve.

a.        Used as a general granular material with less fines.

b.        Probably going to get sand most of the time.  Sand is less expensive and widely available.

c.        Gradation is too open for bridging soft areas in the subgrade.

d.        Can be used to cover soft embankment foundations in thick lifts, such as in swamp treatment construction or with wick drains.

2.        Type B Granular Material has the gradation of Items 304, 411, or 617, except 0 to 20 percent can pass the No. 200 (75 µm) sieve:

a.        Well-graded and stable material.

b.        Can be used to bridge soft subgrades or foundations.

c.        Must be drained to be effective.

d.        Unstable in the presence of free water.

3.        Type C Granular Material has a top size of 3 inches (76 mm):

a.        It is well graded.

b.        Stable material and resistant to water influences.

c.        Can bridge soft areas better than Type B.

d.        Underdrains are difficult to construct through this material.

4.        Type D Granular Material has a top size of 8 inches (200 mm):

a.        It is well graded.

b.        Stable material and resistant to water influences.

c.        Can bridge soft areas better than Type B or Type C.

d.        Underdrains cannot be constructed through this material.

e.        Consider placing geotextile fabric or 304 to prevent piping.  
(See Figures 203.J and 203.K)

5.        Type E Granular Materials are very free draining and open materials:

a.        Coarse aggregates from No. l through 67 are used.

b.        Used to bridge areas that cannot be drained.

c.        Surround with geotextile (712.09, Type D) or Type B or C Granular Material to prevent piping.  (See Figures 203.J and 203.K)

6.        Type F Granular Material only has general requirements:

a.        Well graded material.

b.        Top size from 8 to 3 inches (76 mm) with a bottom size of No. 200 (75 µm) sieve.

c.        Evenly graded material between the top and bottom sizes.

d.        Compactable, stable, and serves the intended use.

e.        Almost never specified.

f.         Can mainly be used to accept materials that do not meet the specific Type A thru E requirements.

Figure 203.J – Fine Material Migration

Figure 203.K – Preventing Piping

Rock (203.02.O)

The following rock description is in the specifications: “Sandstone, siltstone, limestone, dolomite, glacial boulders, brick, and RPCC too large to be placed in an 8-inch (200 mm) loose lift.”  Rock fills are constructed differently than the construction of soil or shale fills; therefore, it is important to clearly identify them in the field.

Rock Identification

It is important to understand the differences in these materials and to have a basic understanding of their origins.

Almost all rock in the state of Ohio is sedimentary rock.  Sedimentary rock is formed by cementation, precipitation from solutions, or by consolidation.

Sandstone is a deposition of sand from rivers, wind, or oceans. This material was cemented together under earth pressure or consolidation.  Coarse sandstone can be readily identified by the sand grains in the field.  Fine-grained sandstone can be confused with siltstone or limestone.

Limestone is calcite formed from ocean deposits of sea organisms (seashells) that were cemented chemically and/or by pressure.  Chert is similar to limestone, but it consists of silica minerals rather than calcite.  Dolomite is limestone with magnesium and calcium carbonate.

Limestone or Dolomite can be readily identified by using a solution of diluted hydrochloric acid.  When hydrochloric acid is dropped on the limestone or dolomite, the acid will fizz or bubble.  The amount of fizzing depends on how much calcium is in the rock.  A pure dolomite may not fizz unless the fines of the rock are tested.

Rock boulders are materials brought from Canada during the glaciers and can consist of just about any stone.  The amount of earth pressure or chemical crystallization greatly influences the hardness of the stone.

Shale (203.02.P)

According to the specification, shale is defined as “A fine-grained sedimentary rock formed from the lithification of clay, silt, or mud.  Shale has a laminated structure, which splits easily (is fissile).  For the purpose of this specification, mudstone and claystone are also considered to be shale.”  Laminated means that it is made up of thin layers or sheets. Fissile means that the layers are easily split apart.

The way we evaluate shale in the field has changed from earlier versions of the specification.  In the past, shale was identified and compacted “as directed by the Engineer.”  The current approach gives the Engineer a systematic approach to evaluate the shale to ensure long-term durability of the shale fill. It enables the Engineer to identify these materials and to distinguish between durable and nondurable shale.

Shale Identification (703.16.D)

Shale is a sedimentary material that consists of silt or clay particles.  Shale was formed when earth pressure squeezed water out of silt and clay mud.  Some shale may be crystallized or cemented together into a stone like form.

Shale is evaluated for durability as described below. The procedure is detailed in C&MS 703.16.D. It is commonly called the Bucket Test. 

1. Obtain a piece of shale that is typical and representative of the rest of the shale.  The size of the piece should be about 6 inches (150 mm).  If a 6-inch (150 mm) sample is not available, then the shale is nondurable.

2. Place the piece of shale in a bucket of water.  Examine the deterioration or slaking of the shale after 48 hours.  If the shale has deteriorated, then the shale is nondurable.

3. If the shale has not deteriorated after being in water for 48 hours, then break down the shale over a 3/4-inch (19.0 mm) sieve by hand pressure.  If 75 percent or less of the shale is retained on the 3/4-inch (19.0 mm), then the shale is nondurable.

4. If more than 75 percent of the shale is retained on the 3/4-inch (19.0 mm) sieve or, then perform a field test for durability.  The field test for durability consists of compacting the shale with six passes of a steel drum roller which has a minimum compaction force of 500 pounds per lineal inch (57 kN/mm) of roller drum width.  Ask the contractor for documentation to verify the roller meets the compaction force requirement.

a. If more than 40 percent of the shale breaks down, by visual inspection, then the shale is nondurable.

b. If less than 40 percent of the shale breaks down, by visual inspection, then the shale is durable.

Different materials will always be mixed together in a fill situation. However, the durability test will give you a good indication of how the material should break down during compaction.  It also provides a ready means to determine the test method to use for compaction acceptance.  The compaction testing procedure for shale is described in Supplement 1015, Compaction Testing of Unbound Materials, but it is also summarized below.

1.        For durable shale, treat it like rock. This means compacting it according to C&MS 203.06.C.  There is no compaction testing for durable shale.

2.        For nondurable shale, if less than 25 percent is retained on the 3/4-inch (19 mm) sieve after the Bucket Test, then compact and test the shale the same as soil.  This means using direct transmission mode of operation for the nuclear gauge and a one-point Proctor test for determining the maximum dry density.  If the amount retained on the 3/4-inch sieve (19 mm) is between 10 and 25 percent, then also use an aggregate correction to determine the maximum dry density.

3.        For nondurable shale, if more than 25 percent is retained on the 3/4-inch (19 mm) sieve after the Bucket Test, then compact and test the shale the same as granular material.  This means using backscatter mode of operation for the nuclear gauge and a test section for determining the maximum dry density.

The color of the shale can be a good indication of the durability of the shale.  Red shale in Ohio is always nondurable, while grey, green, and black shale is generally, but not always, nondurable.  Most durable shale in Ohio is grey or green. Of course, the color of the shale is just a general guideline, and should never be used as the sole criteria for durability. The durability of shale will change depending on the project location and geologic formation.

Random Materials (203.03.L)

By definition, random materials are “Mixtures of suitable materials that can be placed in 8-inch (200 mm) loose lifts.”

Other Allowed Materials under 703.16 and 203.02

Asphalt Concrete (203.02.A and 703.16)

Recycled asphalt concrete is allowed if the material is less than 4 inches and is blended with at least 30 percent natural soil or natural granular material.  The mixing and maximum size requirements are used to minimize the effects of water on the asphalt consistency.  Place a piece of asphalt in a bucket of water and see what happens.

In addition, this material is restricted in 203.03.A & B.

Portland Cement Concrete (203.02.M and 703.16)

Recycled Portland cement concrete is allowed if the material is blended with at least 30 percent natural soil or natural granular material.  Additional mixing requirements are in 203.06.D when used as random material.  This material is further restricted in 203.03.B, E & F.  This material can clog underdrains and produce a lime rich, high pH runoff similar to steel slags as discussed earlier.

Petroleum Contaminated Soil (203.02.K and 203.03.J)

The use of Petroleum Contaminated Soil (PCS) is regulated by law. The legal contamination level of this material is listed in 203.03.J.

This material is usually found around underground storage tanks.  The level of contamination is so low that you may not be able to see or smell the petroleum in the soil.

Section 203.03.J requires that an environmental consultant review the proposed use and test the material.  Submit the report to the Chemical Section in the Office of Materials Management for approval.

Coal (703.16)

Coal is a very lightweight material and is not very durable.  It is allowed in natural embankment materials when it comprises less than 10 percent of the blend.  It is impossible to keep this material out of the fill on large earthwork construction projects.

Recycled Materials (203.02.N, 203.02.R and SS-871)

The specifications define recycled materials as fly ash, bottom ash, foundry sand, recycled glass, tire shreds, other materials, or manufacturing by-products not specifically named as suitable materials in 203.02.R.

The construction and acceptance details are in Supplemental Specification 871.  These materials may have levels of contamination that must be controlled and regulated by law.  Like all other materials ODOT uses, these materials are restricted and have certain engineering properties that must be accounted for in the specifications.

A general discussion of the specification is in Section 202, Regulated Waste Requirements, of this manual.  All supplemental specifications can be found on the Division of Construction Management’s webpage on the Department’s website.

The specification requires environmental and geotechnical approval.  Submit the environmental report to the Chemical Section in the Office of Materials Management for approval.  The geotechnical report and materials acceptance is approved by the Office of Geotechnical Engineering.

Figure 203.L is a typical application of recycled materials.  These materials are used in the inner core of the embankment structure. This controls the chemicals leachate and minimizes the detrimental engineering properties.

Figure 203.L – Typical Cross-Section for Recycled Materials

Figure 203.M details what can go wrong if one uses a recycled material in the wrong fashion.  Read the article and be careful.  Further discussion about the recycled material is beyond the scope of this manual.

Figure 203.M-1 – Tire Fire

Figure 203.M-2 – Tire Fire (continued)

Restrictions (203.03)

Section 203.03 lists materials restricted by the specifications.  These restrictions ensure that the embankment structural integrity is sound in the short- and long-term.  Keep in mind that what seems to be a good product in the field may have serious long-term consequences once in place.  Many of these restrictions were detailed in the previous sections in this manual.

Many embankment materials are allowed in several locations throughout the embankment structure.  These allowable material types are further restricted in the top 2 to 3 feet of the embankment to ensure long-term structural integrity of the pavement.

Some of the general reasons for these restrictions are:

1.        Water accumulates under the pavement and deteriorates the material.

2.        Frost causes some materials to heave and break down to smaller pieces.

3.        The load or stress at this location is higher.

General Construction (203.04)

This section details general information about earthwork construction. No explanation is needed for most of this section except for the following subsections.

Drainage and Maintenance of the Work (203.04.A)

It is vital to the embankment for the Contractor to maintain a well-drained construction operation.  Contractors can provide proper drainage without an enormous effort.

Here is some relevant text from the specifications.

“Maintain a well-drained embankment and excavation operation. … Construct the embankment with sufficient cross-slope to drain in case of rain.”

Maintained cross-slopes ensure that the rain runs off the embankment construction area instead of filtering into the embankment.  It is difficult to remove water once it is in the embankment.  Further embankment construction is compromised once the existing embankment is saturated.

Using a saturated embankment as a haul road can destroy the embankment structure and density.  The following sentences are from the specification.

“If precipitation saturates the embankment construction, stay off the embankment construction until the embankment dries or stabilizes.  Expedite the construction by removing the saturated embankment or dry the embankment by scarifying, plowing, disking, and recompacting the embankment.”

The specifications continue to give the project significant leverage to use with the following passage.

“Throughout the embankment construction operation and at the end of each day’s operation, shape to drain, compact, and recompact the work area to a uniform cross section.  Eliminate all ruts and low spots that could hold water.

If using embankment construction or cut areas to haul on, continuously move the hauling equipment around on the area to take advantage of the compactive effort.  Continually re-grade and compact the haul roads and maintain the construction according to 105.13 and 105.14.”

Contractors will use a multitude of excuses to avoid maintaining a well-drained embankment area.  Some of them are legitimate and some are not.  The project will have to use common sense in evaluating them.

Staged Construction (203.04.G)

Plans will often have fill restrictions that mandate the monitoring of the fill height.  The plans may call for limiting the fill construction to 3 to 5 feet a week and may require waiting periods of 30 to 90 days.

In any case, these restrictions usually mean that the embankment will be constructed on a soft foundation. Limiting the load allows the foundation to consolidate slowly and allows the pore pressure to dissipate so that the embankment does not fail.

In many cases it is required that the project monitor the fill height, pore water pressure, and settlement versus time.  Figure 203.N shows such a plot.

Figure 203.N – Settlement Plot

On the horizontal axis is a plot of time, usually plotted in days.  The vertical axis shows both settlement and the fill height. You can obtain a spreadsheet that will generate the settlement plot from the Office of Geotechnical Engineering.

The plans will usually specify a settlement waiting period.  This is an estimate by the designer as to how long the settlement will take.  However, the actual amount of time it takes for the foundation to settle under the new embankment load is dependent on the actual site conditions, and may be either more or less than the estimate shown in the plans.  The standard plan note says that the Project Engineer may adjust the waiting period based on the settlement readings.  As a general guideline, the settlement is usually considered complete when the settlement readings result in 1/8 inch or less of settlement over a week of time.  The Contractor must include the plan specified waiting period in the construction schedule.  If the waiting period ends up being shorter, then the Contractor can proceed ahead of schedule.  If the waiting period ends up being longer, then the Contractor may be eligible for a time extension due to an excusable delay under C&MS 108.06.

The plans may also require monitoring of the pore water pressure in some cases.  When the pore pressure readings exceed some threshold, the Contractor will have to suspend embankment construction until the pore pressures dissipate.  The plan notes will give the pore pressure threshold, when to take baseline readings, and minimum reading schedule.

Embankment Construction Methods (203.05)

Foundation of Embankments

If you recall from Section 201.04, scalping is not required if the fill height is greater than 9 feet (3 m) and the existing slope is 8:1 or flatter.  Both conditions must apply for the areas to be left un-scalped.  Figure 203.O shows the conditions when scalping is required and when it is not.

Figure 203.O – Scalping Requirements

There is a minimum compaction requirement for all foundations that require scalping. The compaction requirement is 95 percent of standard proctor or 95 percent of the test section maximum value.  This minimum value is easily achieved.  An alternate method may need to be considered if density cannot be achieved.

Soft Foundations

Foundation conditions are occasionally encountered that require treatment to obtain stability either within or beyond what is proposed in the contract documents.  These soft foundation conditions do not take into account the long-term settlement potential. The following details are to allow the project to correctly construct the embankment in order to ensure a stable embankment.  There are two general conditions detailed below:

1.        Moderately Soft Foundation:

a.        Low lying poorly drained areas with high moistures.

b.        Soil unstable due to extreme high moistures.

c.        Equipment rutting less than 12 inches (0.3 m).

d.        Elastic or pronounced elastic movement.

e.        All of the above are constructible with moderate changes.

2.        Severely Soft Foundation:

a.        Peat deposits.

b.        Swampy areas that contain organic soil with high moisture.

c.        Underwater conditions.

d.        Buried equipment.

e.        Un-constructible with soil replacement.

The nature and degree of the foundation instability will vary considerably.

Moderately Soft Foundation

The first step in determining the proper treatment for a soft foundation and ensuring embankment stability is to determine and consider the following:

1.        Planned embankment height above the foundation.

2.        Allowed construction time frame.

3.        Nature of the foundation material.

a.        Moisture content.

b.        Location of free water.

c.        Location of possible outlets for drainage.

d.        Extent in depth and area of unstable material.

4.        Type of embankment material.

The following types of corrective measures have been used successfully for many years.  Measures required to correct unstable foundations often are apparent when the cause and extent of the instability are known.  The following sections consider three different, moderately soft conditions that can occur during construction.

Embankment heights greater than 12 feet (4 m)

The higher the fill height above the foundation, the better chance the project has in bridging over soft foundation locations with very little additional expense.

Section 203.05 allows the Engineer to increase the lift thickness to bridge soft foundation locations.  The specifications refer to areas that do not support the weight of the trucks or hauling equipment (areas with less than 12 inches (305 mm) of rutting or a moderately soft foundation).  For areas with more than 12 feet (4 m) of fill, this method should be the first alternative utilized.

Section 203.05 allows the following technique when placing material over the soft foundation:

1.        Dump successive loads of material in a uniform lift.

2.        Do not exceed the lift thickness required to support the equipment placing the material.

3.        Manipulate, blade, distribute, level, and doze the material until the area is stabilized.

4.        Once the bridging has been accomplished, construct the remaining lifts according to 203.06.

This is standard practice in soft foundation locations.  Density controls during this initial construction are not required.  If the soft foundation is just wet and does not have standing water, then soil dryer than optimum may be used.

If the foundation has standing water, consider placing construction underdrains or ditches to drain the soft areas (if the area can be drained).  If the areas cannot be drained, then use rock, granular material, or hard durable shale in 1 to 3 foot lifts (0.3 to 1 m).

Observe the embankment stability once the bridging material is in place and make adjustments as required.  Reevaluate the conditions when the embankment is 6 feet (2 m) below grade.

Embankment heights less than 12 feet (4 m), but more than 6 feet

Investigate the source of the problem.  Evaluating foundation conditions is similar to evaluating the condition of a subgrade.  Before determining the solution, first evaluate the foundation conditions by digging test pits, evaluating the soil borings and observing the rut depth.

Use the section, The Investigation, under Item 204 of this manual, Figure 204.G Subgrade Test Pit Investigation and Figure 204.H Subgrade Treatment Chart, to help evaluate the foundation.

Determine the average N, average U, and rut depth values using the above sections.  Evaluating soft subgrade and soft foundations is similar with a slight variation.  If the soft material is less than 2 feet (0.6 m) in depth, remove it and replace with soil.

If the average U > 0.5 tons/ft², average N > 5, and the rut depth is less than 6 inches (150 mm), then use an initial lift of soil that is about 1 to 3 feet (0.3 to 1 m) thick.  The soil should be less than optimum moisture.

Do not use soil to bridge areas with standing water or in conditions where some embankment has already been placed as in the previous section.

If the soil conditions are worse than these values or the rut depth is more than 6 inches (150 mm), then use an initial lift thickness of 1 to 3 feet (0.3 to 1 m) of rock, granular material, or hard durable shale. 

If the slope allows the area to be drained, drain the soft foundation by using construction underdrains or ditches.  Continue to evaluate the conditions when constructing the remaining fill and adjust when required.

Embankment heights less than 6 feet (2 m)

If the source of the problem has not been previously evaluated, then investigate the source of the problem as detailed in the previous section.

Determine the average N, average U, and rut depth values.  Again, evaluating soft subgrade and soft foundations are similar with slight variations.

To determine the correct fix, use the Subgrade Treatment Chart in Figure 204.H and find the correct undercut depth or stabilization depth.

Subtract the fill height from the recommended undercut depth to determine the required undercut depth in the foundation.  See Figure 203.P

Figure 203.P – Fill Undercut Depth

Example:

Given:

New Construction Project

2 feet (0.6 m) of fill

U=0.5 tons/ft², N=5 and Ruts > 6 inches (150 mm)

From Figure 204.H Subgrade Treatment Chart,
recommended undercut depth = 3 feet (1 m)

Solution:

Required undercut is 1 foot and place 3 feet (1.0 m) of Granular Material for the fill.  As an alternative, consider stabilizing the foundation with cement or lime and then placing 2 feet (0.6 m) of stabilized soil.

Severely Soft Foundations

Severely soft foundations are conditions that cannot be constructed without using rock or granular material.  These conditions usually are in standing water or even underwater.  Construction equipment either gets buried in the areas or cannot operate in these locations.  Peat deposits or swampy areas that contain organic soil with high moisture are the norm in these locations.

Unless these areas are called out in the plans, it is best to contact the District Geotechnical Engineer or the Office of Geotechnical Engineering to evaluate the depth and extent of the required undercut.

This section examines two different methods to remove and replace this soft material:

1.        Total Excavation Method.

2.        Partial Excavation and Displacement Method.

There will be plan notes associated with these methods.  The following is a brief description of the construction methods of these two.

Total Excavation Method

Below is a cross-sectional view of the total excavation method.  This method, as the name implies, is used to where all of the soft material can be removed down to a firm foundation.

Figure 203.Q – Cross-Section View of a Total Excavation

The excavation and backfilling progresses across the soft foundation for depths up to 20 feet (6 m) deep or the reach of the track hoe.  Below is a plan view of the same operation.  The filling progresses at the same time as the excavation.

Figure 203.R – Plan View of the Filling and Excavation

Many times the excavation is performed on the same side as the filling, the embankment side, but this takes some coordination by the Contractor.  Below is the longitudinal view of the same operation.  The filling operation normally keeps the fill at least 1 foot (0.3 m) above the soft material of water level.

Figure 203.S – Longitudinal View of the Total Excavation

Partial Excavation and Displacement Method

At times it is economical to only remove portions of the soft foundation.  The cross-section view is shown below.

Figure 203.T – Partial-Depth Removal

Below is a longitudinal view of the partial depth operation.  A surcharge of material is required to displace the soft material forward as much as possible.  The work needs to progress across the soft foundation such that soft material does not get entrapped in the replacement material.  This is true for either full- or partial-depth replacement.

Figure 203.U – Longitudinal View of Partial Depth

In these operations, the plan will denote which method of excavation is to be used for the work.  In the past, the volume of the work was very difficult to quantify.  A new plan note has been developed to simplify this measurement.  The designer will choose the type of replacement material that will replace the soft foundation material.  Use a table similar to the one below to convert the weight of the replacement material to volume.

Table 203.A – Conversion Factors for Replacement Materials

Granular Materials

Dumped Rock Fill

Type

Tons/Cubic Yard

Type

Tons/Cubic Yard

A

B

C

D

E

1.6

1.9

1.8

1.8

1.6

A

B

C

D

1.9

1.9

1.8

1.7

The replacement material may be granular material or dumped rock fill.  Prior to the material being dumped into the soft foundation, weight tickets are taken to finalize the replacement quantities estimated in the plans.

After the quantities for the replacement materials, in tons, are known, the quantity is converted to cubic yards using the above table.  This cubic yardage is used to determine the quantity of excavation to be paid.  This simplifies the measurement of the material that normally cannot be measured directly in the field.

Materials

The material used for this operation may be granular material or rock fill types.  Usually Granular Material Type C or D is used for these conditions.  Dumped Rock is usually specified for depths greater than 10 feet (3.3 m).  The project should check the potential for piping.  See Figures 203.J and 203.K.

Disposal of Material

The unsuitable excavated material may temporarily be left in place or used for flattening adjacent slopes outside the plan lines.  This material must either be shaped into the final slope or disposed of 2 weeks prior to paving the project.

Consolidation Method

There is another method to bridge a soft foundation.  It is the consolidation method.  It was mentioned in Section 203.04.G.  It is beyond the scope of this manual but a typical cross-section is presented below.

Figure 203.V – Consolidation Method

A layer of sand is placed to bridge over the soft foundation usually around 3 feet thick.  Wick drains are then placed through the foundation soils.  These wick drains allow the pore pressure to dissipate faster as the fill is constructed.

Benching

Beginning with the 2002 C&MS, the language was more explicit than in the previous versions of C&MS.  This new language was put in C&MS to ensure that benching is properly performed in the field.  Figure 203.W details where benching is required.  Benching is required for all embankments placed on or against a slope steeper than 8:1.  Of course, the existing slope has to be scalped first.  This applies to all embankment areas whether the existing embankment cross-slope is in the transverse or the longitudinal direction.

Figure 203.W – Benching Required

Figure 203.X details the bench into the existing embankment.  For side hill fills, the existing embankment is physically notched out and connected to the new embankment.  Benching requires horizontal cuts in the existing slope.

Figure 203.X – Benching

The bench needs to be wide enough to blend the new embankment with the existing embankment.  In Figure 203.Y, the total width between point A and B must be the width of the dozer blade and the compaction equipment.

Figure 203.Y – Benching in New Embankment

If the plan calls for a new embankment, or the distance between C and B is less than a blade width or about 8 feet, then the existing embankment must be benched in the difference, which is the distance from A to C.

In Figure 203.Z, the horizontal distance between points D and E is about 4 feet (1.3 m). Therefore, the existing embankment must be benched into about 4 more feet (1.3 m) to complete the bench.

Figure 203.Z – Sliver Fills

Bench into the slope as the embankment is placed and compact into layers.  Begin each bench at the intersection of the existing slope and the vertical cut of the previous bench.  The re-compaction of the cut materials is required.

Benching is nothing more than a side hill foundation.  Benching knits two embankments together to ensure that a failure plane does not occur.  Figure 203.AA details typical benching seen on some plans.

Figure 203.AA – Typical Benching

In this case, the designer anticipated that there was a stability problem, or weak soils, in the existing embankment (or both).  This is called special benching.

Side hill embankments present unique problems; they may be stable when originally constructed, yet become unstable later.  The result is usually a landslide.

If the bench is not benched far enough into the existing embankment, a weak plane can develop as shown in Figure 203.BB.  A failure may occur along this weak plane and the bench material will move laterally. The project should evaluate the existing soil conditions and determine if more benching is required than is shown on the plans or required by the specifications.

Figure 203.BB – Benching Problems

Bench Drainage

In many cases, the main cause of an embankment benching failure is water related.  Seeping water into the embankment from the side hill or foundation can cause considerable instability in the existing and the new embankment.  Due to many factors, water is an elusive quantity to capture during the design phase.  Notice in Figure 203.BB how water can move into the bench material and weaken it.

Special attention must be given to side hill embankments.  Consult the plans and soil profile to see where special benching, if any, is required; to see whether or not spring drains are provided; and to see if any potential spring or wet zones are mentioned.  The areas should be inspected in detail for possible springs.  In dry seasons, green or lush vegetation are often indicative of a semi-dormant spring that may become active during prolonged periods of precipitation.  If spring zones are encountered, and no spring drains are provided in the plans, then drains should be added to the work. 

If there is any indication of water, drainage should be added if it is not already detailed in the contract.  The following pages detail typical solutions to use in the field.

Spring drains are detailed on the plan by plan note D109 and on the second sheet of Standard Drawing DM 1.1.  Plan note D109 can be found in Location & Design Manual – Volume 2, Drainage Design. Links to the Location & Design Manuals and the standard drawings can be found on the Design Reference Resource Center on the Department’s web site.

The standard drawing is partially shown in Figure 203.CC.  The standard drawing does not call for it, but it is recommended to use non-perforated pipe outside the No. 57 stone and perforated inside the No. 57 stone.  Wrap or coil the pipe inside the No. 57 stone for maximum efficiency.  Completely wrap the No. 57 stone with Type A geotextile fabric.  In many cases No. 8 stone can be substituted for the No. 57 stone without sacrificing much drainage capacity and it also reduces the risk of piping.  The application of a spring drain is used for local wet spots.

Figure 203.CC – Spring Drains

Severe Bench Drainage Problems

Drainage always should be added when the benching embankment is placed next to a rock or shale cut.  In this case, add drainage along the entire length and width of the shale/rock benching interface.  Experience has shown that water always leaches from this interface.  If a large quantity of water is coming into the bench, or water is leaching from several locations and elevations, drainage should be added across the entire bench face.  In both examples above, a different approach needs to be taken due to the severity of the water issue.  There are two potential solutions to the severe drainage problems.

Adding Drainage when Benching from the Top Down

If the slide repair benching plan has 1 to 1 back slopes and consists of minimum 10 foot wide and high benches and the slope can be excavated from the top of the cut all the way to the bottom, then the following drainage should be considered.

The use of geotextile fabric and No. 8 stone to take the water flow, as detailed in Figure 203.DD, is one solution to solve the drainage issue.  The geotextile is used to stop the migration of fines into the No. 8 stone.  Notice that the geotextile fabric is used on both sides of the No. 8 stone to prevent migration from either side.

Figure 203.DD – Severe Water Problems in a Bench

The geotextile fabric generally used is 712.09 Type A geotextile.  The drainage aggregate can be No. 8, No. 9, or No. 89 size.  The drainage pipe going into the page is a 6 inch, Item 605, 707.33 perforated pipe.  The lateral drain is a 6-inch, Item 611, Conduit Type F non-perforated.  This lateral drain backfill should be surrounded by at least 12 inches (300 mm) of sand.  This will provide a secondary outlet if the pipe gets clogged.

Figure 203.EE – Multiple Bench Layout

These benches can be interconnected and outlet as detailed in Figure 203.EE.  Section A is the No. 8 stone and the geotextile fabric.  Section B is the non-perforated pipe with an outlet into Section F.  Notice that the bench and the pipe are outlet using a one percent grade or 100:1 slope.  This ensures that the water can effectively be removed from the system without leaching into the soil mass.

Figure 203.FF – Detail for outlet F

Figure 203.FF details the outlet configuration. Balloon number two is a 20 mil plastic to prevent the water from entering the soil along the slope.  Balloon number one details 712.09, Type D geotextile fabric, which serves to protect plastic from getting torn during rock installation.  Balloon number three details the Rock Channel Protection.  In this case, the rock type was Type C.  This rock type should be used in most cases.

Figure 203.GG – Lower Bench Outletting

Figure 203.GG details the lower benching.  In the above slide repair, the lower embankment was preexisting and did not require reconstruction,  but the lower benches did need to be drained.  The bench and pipe drainage into the page of the cross-section was sloped at a one percent grade.  The slope of the outlet E from left to right is sloped at a one percent grade.  The outlet pipe excavation was about 20 feet deep.  This is a high risk operation during construction.  If necessary, this construction can be done without trench boxes or laying back the slope.  The trench is excavated in maximum 50 foot lengths.  The pipe is jointed together above ground and dropped into the hole.  Grade is kept by conventional methods or by GPS.  In this case, sand is dumped in the trench up to an elevation 580.  The sand should be hoe rammed in place in thick lifts.  In this case, compaction requirements are secondary to the ability of keeping the trench from collapsing. Keep the open trench as small as possible and no personnel are to enter the trench during these operations.

Figure 203.HH – Detail for Slope Protection G

After the outlet is constructed, the outer slope will be sand for about 6 feet wide.  Detail G in Figure 203.HH, details the erosion protection required.  A 712.09 Type D geotextile is placed under Type C Rock Channel Protection.  The width of the material should be the width of the sand.

Figure 203.II – Top View of the Drainage

Figure 203.II details the plan view of the drainage pattern in the slide repair.  You will notice that the outlets are spaced at 200-foot intervals and the benches are sloped at a one percent grade toward them.  Notice that the high point on the bench is 100 feet from the outlets and goes in both directions toward the outlets.

When the benching cannot be performed from the top down or the benches are small, another method of adding drainage to the benching plan needs to be considered.  Figure 203.JJ, shows adding a 20-foot drainage trench to drain an upper, unstable slope (to the left) and to prevent the embankment from becoming saturated.  The drainage into the page is sloped at a one percent grade.

Figure 203.JJ – Using Trenching and Sand

Since this trench is around 20 feet deep it is a high risk operation during construction.  If necessary, this construction can be done without trench boxes or laying back the slope.  The trench is excavated in maximum 50-feet lengths. By keeping the trench length to a small interval it minimizes the potential for collapse or upper slope damage.  The pipe is jointed together above ground and dropped into the hole.  Grade is kept by conventional methods or by GPS.  Sand is dumped in the trench approximately 3 feet below ground level.  The sand should be hoe rammed in place in thick lifts.  Compaction requirements are secondary to the ability of keeping the trench from collapsing.

In Figure 203.KK below, the above trenching technique is expanded to drain the entire counter berm.  The drainage at the toe is provided by the rock fill while the three trench drains to the left drain at third point intervals along the existing new fill interface.  The center two sand drains are placed at the interface of the existing ground and the new embankment.  The construction of the middle two sand drains is slightly different than the other sand drain, but only slightly.  The embankment is constructed to the top elevation of the sand trench and the sand trench, pipe, and outlets are constructed as previously described.

The sand that is generally used for these operations is asphalt, concrete, or masonry sand.  There is a possibility that the soil will pipe into the sand or the soil will clog the sand.  The possibility of this happening is considered a small risk and is beyond the scope of this manual.

In Figure 203.JJ, the pipe in section B is perforated and wrapped with geotextile fabric to prevent the sand from piping in the pipe.

Figure 203.KK – Multiple Benching with Sand

Figure 203.LL details the plan view of the drainage system, which is similar to that previously detailed.  The outlets are spaced every 200 feet and everything drains at a one percent slope.

Figure 203.LL – Plan View of Drainage

Spreading and Compacting (203.06)

This section covers a general description of spreading and compacting materials.  A more detailed explanation can be found in Section 1015 Compaction Testing of Unbound Materials.

The procedures outlined in this section will make or break the quality of the earthwork construction.  Control over the lift thickness and compaction of the materials is vital to the success of the project.

Certain materials require compaction at thinner lifts than others in order to obtain their maximum strength.  Other materials can be compacted in thicker lifts without sacrificing quality.  Some materials require the addition of water to help the compaction effort or to help break down the material, while other materials require mixing to get the desired results.

All embankment materials, except for rock in 203.06.C. and RPCC in 203.06.D, are spread in horizontal, loose lifts, not exceeding 8 inches (200 mm).  All embankment material lifts, except for rock and durable shale, are compacted to a specified density and moisture requirement in 203.07.

The material is spread using dump trucks, scrapers, and dozers.  In general, a footed drum roller is used to compact rock, shale, clay, and silt material.  Granular materials are generally compacted using a smooth drum vibratory roller.

To record the embankment construction operations, an inspection sheet was created to help document the work: the CA-EW-12 Daily Earthwork Inspection Form.  There are several sections to check off on the form that denote project information, location of the work, type of equipment used, and embankment operation information.  This form should make it easier for the earthwork inspector to determine what the minimum inspection requirements are during the earthwork operations.

Soil and Granular Embankment (203.06.A)

Use a maximum lift thickness of 8 inches (200 mm) for soil and granular embankment.  Compaction acceptance for soil is based on a percentage of maximum dry density.  The appropriate maximum dry density value is determined from a one-point Proctor test, one-point Proctor test with aggregate correction, or a test section.  Compaction acceptance for granular material is also based a percentage of maximum dry density, but the maximum dry density value is always determined from a test section.

These methods for determining the maximum dry density are covered in Section 1015, Compaction Testing of Unbound Materials, of this manual.

Shale (203.06.B)

Shale is consolidated mud.  Shale may seem hard, but in many instances it can be broken down to soil size with very little effort.  See 203.02.P and 703.16.D in this manual for a full description of the material.

Some hard, durable shale can be excavated or blasted in very large sizes.  Contractors control the size of the material by the way they blast the material.  During the typical rock blasting operation, the bench height/burden (L/B) ratio is greater than one, the production hole spacing (S) is 10 to 15 feet (3.3 to 5 m), and the production hole diameter (D) is 6 inches (150 mm).  These dimensions are typical in order to maximize production.  In addition, it generally leaves large chunks of rock or shale.  These large pieces are fine for rock fills, but are not conducive to shale fills.

To produce smaller shale or rock fragmentation, the blaster can increase the L/B ratio to about 3, decrease S to 6 to 8 feet, and reduce D to about 4 inches (100 mm).  These dimensions are changed in a trial and error method.  The most efficient method depends on the shale and rock formations.

If the Contractor does not control the material size during the excavation or blasting, the amount of spreading, manipulation, compacting, and watering will be extensive in order to get the material into 8-inch (200 mm) lifts.

All shale material is placed and compacted in 8-inch (200 mm) lifts.  If the material is placed and compacted in thicker lifts, then a situation such as in Figure 203.MM can occur.  Loose, nondurable shale, intermixed within the lift can later deteriorate when water runs though the material.

Figure 203.MM – Thick Lift of Shale

In many cases, when thick lifts are used, the compaction in the top 8 inches (200 mm) may pass.  If the top 8 inches (200 mm) is removed, the lower material is made of loose and large chunks of soft shale.

Figure 203.NN details what happens when shale is not properly placed and broken down.  The embankment load on the shale, along with the water going through the embankment, can cause the nondurable shale to break down.

Figure 203.NN – Inadequate Shale Compaction and Breakdown

In order to ensure long-term durability, the project needs to determine how much to break the shale down in the field.  The amount of breakage during construction is directly related to the durability of the shale.  The durability is correlated to the Bucket Test and roller pass methods in the specifications.

The specifications require that the shale be tested for compaction and broken down according to the Bucket Test and the subsequent roller pass evaluation.

A summary of this evaluation follows:

1.        Perform initial test for durability in 703.16.D (Bucket Test).

2.        Consult the following:

a.        If less than 25 percent is retained on 3/4-inch sieve, then shale should be broken down to soil size.

b.        If 25 percent to 75 percent is retained on 3/4-inch sieve, then an even percentage of soil, small-, and coarse-sized shale are obtained (maximum contact with all particles).  Shale should have a granular texture when properly broken down in the field (see Figure 203.OO).

c.        If more than 75 percent is retained on 3/4-inch sieve, field test for hardness (703.16.D).

3.        Use six passes with rollers specified in 703.16 to field test for durability.

4.        Consult the following:

a.        If greater than 40 percent breaks down, break material into a granular texture as detailed in Figure 203.OO.

b.        If 40 percent or less breaks down, use the procedure in Section 203.06.B in C&MS (Durable Shale): 10 passes with a 15 ton roller and fill the voids.

Figure 203.OO – Granular Texture Shale

The above procedure is a systematic approach to evaluating potential shale breakage in the field.  In practice, field results will vary because of variability of shale and the mixing of different types of shale and rock.  Some judgment is required during construction.

The most important factors in the long-term quality of shale fills are:

1.        Water shale until the material is at least 2 percent above optimum moisture throughout the lift.

2.        Manipulate or mix by dozing until a maximum 8-inch (200 mm), loose lift is achieved.  Remove large chunks of shale or rock that exceed this lift thickness.

3.        Compact each lift to a maximum dry density, except for durable shale.  Use 10 passes with a 15 ton roller in 203.06.B for durable shale.

4.        Typically about 5 to 10 passes are sufficient for compaction of nondurable shale.

Rock (203.06.C)

Maximum loose lifts are as follows:

1.        Six inches larger than the largest rock piece with a maximum lift thickness of 3 feet (1 m). Some examples follow for clarification:

a.        The maximum rock size in a 3-foot lift is 2-1/2 feet.

b.        If the largest rock size in a lift is 1 foot, then the maximum lift thickness is 1-1/2 feet.

2.        Near bridges, within a length of 6 times the height of the fill at the abutment, use less than 18 inch (0.5 m) lifts. 
Example:  Fill height is 20 feet (6 m), thus within 120 feet of abutment.               
(20 × 6 = 120 feet)

The rock fill construction is outlined below:

1.        Distribute full width of the lift.

2.        Evenly distribute the larger rocks.

3.        Reduce the voids.

4.        Place the smaller rock in the upper portion of the lift.

5.        Compact with 8 passes of a 10 ton (9 metric ton) roller.

When using other embankment materials with rock, use rock as:

1.        Base of the embankment. It provides better support.

2.        On the outer portions of the embankment. It provides better drainage.

3.        Place the larger rocks on the outside side slopes. It provides better drainage.

Use other embankment material as follows:

1.        On the inner portion of the fill.

2.        Keep the top higher than the rock.

3.        Construct wide enough for compaction.

4.        When rock is on top of other embankment material, construct at a side slope grade of 4 percent prior to placing the rock.  This provides better drainage.

When the rock fill contains more than 15 percent shale, compact like a shale fill.

Random Material (203.06.D)

Random materials are a wide variety of materials which do not fit any other groupings.  They may be rock mixed with soil, brick, asphalt mixed with soil, or Portland cement concrete mixed with soil.

Soil mixed with any other random material must be at least 2 percent below optimum.  This will help fill the voids and create a stable embankment.

Recycled asphalt or concrete are mixed with at least 30 percent natural materials.

Random material mixtures are placed in 8-inch lifts, except for RPCC:

1.        Maximum size of the RPCC is less than 3 × 3 feet (1 m).

2.        The mix is dozed and mixed to fill the voids.

3.        Lift thickness is less than 12 inches (300 mm).

4.        Use 18 inch lifts (0.5 m) when the lift is more than 50 percent RPCC.

5.        Compact the natural material to a test section maximum.

Compaction and Moisture Requirements (203.07)

Except for granular material types D and E, rock, and durable shale, the moisture and density controls in this section apply.  Perform all compaction tests according to Supplement 1015.  This supplement is detailed in Section 1015 Compaction Testing of Unbound Materials.

Moisture Controls (203.07.A)

Water is added or removed from a material in order to obtain the necessary density and stability.  Note: for embankment material, there is no explicit range of acceptable moisture content (e.g. within 3 percent of optimum moisture content).  The criteria for acceptable moisture content are that the Contractor can obtain the necessary density and stability.

Dry or add moisture throughout the lift.  Expedite and manipulate the material by using plows or discs.  For soils with pronounced elasticity or deformation, reduce the moisture content to ensure stability.

In a fill situation without a soft foundation, heavy equipment may deflect the soil, but no permanent rutting or cracking should be evident afterwards.

Some soils require moisture contents 5 percent below optimum to ensure stability.  Materials such as A-4a, A-4b, and A6a’s are notorious for this problem.  These materials are difficult to compact during marginal weather conditions and directly after a rainy day.

The elasticity may be caused by foundation conditions.  See Materials 203.02, Elasticity and Deformation of Soils.

Do not mix shale in the lifts to reduce the moisture content.  The shale will bring the moisture down, and then break down later causing settlement or a landslide.

Compaction Requirements (203.07.B)

Table 203.07-1 details the Embankment Compaction Requirements.  The percentage is based on the maximum dry density of the soil.  This table is used for materials where the maximum dry density is determined using a one-point Proctor test or a one-point Proctor test with aggregate correction.

Table 203.B – Embankment Compaction Requirements

Maximum Dry Density (lb/ft³)

Minimum Compaction Requirements in Percent of Maximum Dry Density

90 to 104.9

102

105 to 119.9

100

120 and more

98

Test sections are required to determine the maximum dry density for granular materials and some other materials.  If a test section is used then the following apply:

1.        Use at least 98 percent of the maximum dry density obtained in the test section for acceptance in the production area.

2.        Use the same number of passes used in the test section for the production areas.  Reduce the number of passes if detrimental to the compaction.

3.        Construct a new test section when the material or supporting foundation changes.

4.        Reduce the moisture content if the material becomes unstable.

More detail can be found in Supplement 1015 Compaction Testing of Unbound Materials.

Method of Measurement (203.09)

This section of the manual briefly outlines some of the methods used to determine earthwork quantities.  Methods described in this section are acceptable for making this check.  Many of these methods are outdated due to current GPS (GNSS) systems, but they are still presented.

Specification Requirements

The specifications require that the average-end-area method be used to determine volumes of earthwork for payment.

End Area Determinations

There are many acceptable methods for determining end areas for earthwork computations.  Any method that gives accurate determinations may be used.  Some of the most common methods for determining cross-section end areas are as follows:

Planimeter

In this method, an instrument with a wheel and a graduated dial is run around the perimeter of a cross-sectional end area.  The area is found by multiplying the reading on the dial by a constant factor or by setting a factor on the planimeter and reading the area directly from the planimeter dial.

Counting Squares

In this method, the number of unit squares in a section is counted.  This is only practical in very small sections.

Stripping

This is a method of tallying unit squares by making successive marks on a strip of paper to measure unit strips, accumulating all unit strips on a cross-section and converting to total cross-section area.  This method is simple, rapid, and keeps the chance of error to a minimum.

Computer Method

In this method, data from cross-sections (usually in coordinate form) is input into a computer program, which follows a program set-up to finish areas and volumes.

CAD

Most plans are developed using Computer Aided Design (CAD) programs.  The earthwork calculations are detailed in these files.  Contact Production for these calculations.

Geometric Method

In this method, the section is broken into areas, such as triangles and trapezoids.  Each area is then calculated by its geometry.  The total area is found by the sum of the individual areas.

Arithmetic Calculation

This method calculates end area using a formula.  Data for the formula is taken from a cross-section (or field notes) that show elevation and distance from a base line for each break in the cross-section line.  A pocket calculator can be used for this calculation.

Determination of cross-section end areas by this method is exact and any two persons using the same information (field notes) will obtain the same answer, providing no errors are made in the calculator manipulation or arithmetic calculations.  There is only one correct answer.

The two methods are described and illustrated in Figures 203.PP and 203.QQ.

 Figure 203.PP – End Area Determination Method 1

Figure 203.PP-M – End Area Determination Method 1 (Metric)

Figure 203.QQ – End Area Determination Method 2

Figure 203.QQ-M – End Area Determination Method 2 (Metric)

Volume Determination

The end areas of English plans are detailed in square feet (ft²), while end areas on metric plans are detailed in square meters (m²).  Make the appropriate volume calculation shown below using the end area found in Figure 203.PP or 203.QQ.

Formula

For base lines and center lines on tangent, and for center lines on curves where the center line of the curve coincides with the center of mass (centroid) of the cross-sections, the formula for computing volume from end areas are as follows:

English Units

Where

V     =      Volume in cubic yards (yd³)

A₁    =      Cross-section one end area in square feet (ft²)

A₂    =      Cross-section of other end area in square feet (ft²)

L      =      Distance between A₁ and A₂ in feet (ft)

Metric Units

Where

V     =      Volume in cubic meters (m³)

A₁    =      Cross-section one end area in square meters (m²)

A₂    =      Cross-section of other end area in square meters (m²)

L      =      Distance between A₁ and A₂ in meters (m)

Table

Figure 203.RR shows a table used for determining cubic yards (yd³) from the sum of end areas for sections 100 feet apart and for conditions described above.  This table cannot be used on metric projects.

Figure 203.RR – Cubic Yards for the Sum of the End Areas

Earthwork Quantity Calculations

Figure 203.SS Earthwork Calculations depicts a form that can be used to summarize the earthwork calculations.

Figure 203.SS – Earthwork Quantity Calculations Form

Figure 203.TT shows a completed calculation form.

Figure 203.TT – Completed Earthwork Quantity Calculations Form

Volume Determination on Curves

Where cross-sections are at right angles to curve center lines, and the center line is not located at the center of mass (centroid) of cross-sections, corrections must be applied to volume calculations in order to obtain accurate results. This is especially true for curves of short radius’s, such as those commonly used on ramps.  Inaccuracies of considerable magnitude may result unless proper corrections have been used in calculating earthwork volumes.  General methods for determining accurate quantities in such cases are detailed in Section 1310.3.2 and Figure 1310-1 in the Location & Design Manual – Volume 3, Highway Plans.  Links to the Location & Design Manual can be found on the Design Reference Resource Center on the Department’s website.

Basis of Payment (203.10)

There are a multitude of statements that denote when the Department will and will not pay for earthwork quantities based on different field circumstances. The project should review this section.  In this manual we will focus on the final quantity measurements.

The GPS (GNSS) methods are not detailed in Section 203.09 or 203.10 of this manual.  Electronic devices connected to graders or dozers are allowed in Item 623 of the C&MS.

Final Earthwork Quantities

Check measurements are made in areas where earthwork is being performed.  A sufficient number of these checks must be recorded according to the instructions in this manual to provide a satisfactory record of the checks.  The purpose of these measurements and records are:

1.        To ensure that earthwork is being constructed to plan lines within specified tolerances.

2.        To provide a simplified method of earthwork measurement so that payment may be based on corrected plan quantities.

This will result in the savings of engineering man-hours required to arrive at payment quantities and make it possible for the Contractor to receive prompt final payment after the completion of the work.

Measurement by Final Cross-Sections

Final cross-sections of roadway earthwork are usually not required, provided that the plan quantities are checked for accuracy and adequate checks have been made (and recorded) during construction.  This establishes that plan quantities of earthwork have been performed within specified tolerances.

Final cross-sections may be called for where, by inspection or other knowledge of the project, it is indicated that measurement by final cross-section is necessary or desirable.

Procedure for Check Measurements and Check Calculations:

1.        Before earthwork construction has begun, make a plan-in-hand inspection to verify the ground line shown on the plan cross-sections, and if significant changes in topography indicate the need for additional cross-sections at intermediate locations.  Where this inspection indicates the need, arrange for further checks by ground or aerial survey.

2.        State in the project diary that this inspection has been made.

3.        Ensure that slope stakes are set by the calculation method.  The initial point for calculations should generally be a profile grade elevation.

4.        Obtain a copy of the survey notes, whether the staking is done by a Department or Contractor survey crew, and plot horizontal and vertical locations of the slope stakes on the cross-section sheets. Check the accuracy of original plan ground cross-sections at slope stake locations.  Record errors noted and correct plan sections promptly.

5.        Check the accuracy of the original ground lines shown on plan cross-sections as follows:

a.        In order to verify the original ground lines shown on plan cross-sections, the Engineer shall field check cross-sections every 300 to 500 feet (100 to 150 meters) by either ground or aerial survey methods prior to the beginning of construction operations.  If any appreciable variations from plan elevations are found, check sections must be taken at closer intervals in order to determine the extent of plan errors and amount of additional cross-sectioning required to provide accurate earthwork quantities.  Use the corrected ground line where plan cross-section lines have been found in error.

b.        Plan quantities resulting from computations that have been properly documented and made a part of the project records are to be used as final pay quantities. Any additions to, or deductions from, plan quantities necessitated by change orders shall be computed by project personnel in order to determine final pay quantities for adjusted items.

c.        The Department will make revisions to the pay quantity for changes for the following:

                                                               i.      Total quantity changes greater than 1,000 cubic yards.

                                                              ii.      Two consecutive end areas varying by more than 5 percent.

                                                            iii.      Undercutting.

                                                            iv.      Foundation settlement.

                                                              v.      Changes in the grades or slopes.

                                                            vi.      Removing slides.

                                                           vii.      Arithmetic errors.

d.        Final pay quantities computed or adjusted by project personnel shall be checked in the Project Office of the District Office by competent Department personnel who have been assigned to the project for construction control, supervision, etc.

e.        All computations of adjustments shall be properly validated by the signed initials or names of persons who computed the adjusted pay quantities and those who performed the checking operations.  Also, the dates that these functions were performed shall be indicated.  These adjustment computations shall be made a part of the official project records.

6.        Where the plan quantities have been checked and validated on the plans or on computation sheets provided by the design unit preparing the plans, it is not necessary during construction to make a detailed check of accuracy of plan earthwork quantities.  If an error in validated plan quantities is noted, recalculate the end areas and volumes in question.  Check all plan earthwork quantities for accuracy when plan quantities have not been checked and validated on the plans or on computation sheets provided by the design unit preparing the plans.  Especially check locations where there are curves of short radius, such as ramps.  Plan quantities are frequently in error by significant amounts at such locations.  Where plan quantities are not correct, strike out the plan figures and write in the correct figures.  Check the summary to see that quantities have been transferred accurately from cross-section sheets.

7.        Make check measurements during construction to ensure work is being done within allowable field tolerances.  Project personnel should perform these checks, supplemented by occasional use of the Department survey crew when needed.  Make sufficient checks to ensure that the work is being performed within allowable tolerances.  The frequency of these check measurements should be determined by the Engineer.

8.        The Contractor is required to correct all deviations from plan lines in excess of allowable tolerances as determined by check measurements.  During rough grading, it is acceptable to permit cuts and fills to exceed tolerances by an amount which will be corrected during fine grading by practical construction methods.  In the case of fills, require prompt corrections of deviations inside allowable tolerances so that specified compaction of the outer edges will be obtained as the work progresses.  In the case of deep cuts with steep slopes in rock or shale, prompt correction of deviations in excess of allowable tolerances is required, so that adjustments can be made as the work progresses while the slope areas in question are within reach of the equipment being used.

9.        Record necessary check measurements in appropriate notebooks, inspector report forms, or daily entry in the project diary.  These notations should state the location where check measurements were made.

10.     Maintain a set of plan cross-sections in the Project Office.  Plot check measurements, changes, and errors in plan lines on all projects where there is authorized work beyond plan lines, such as excavation of soft subgrade. Measurements of this authorized, additional work are required.

Borrow Pay Quantity

Specifying borrow happens rarely and only when the measurement in the final location is impractical.  An example would be underwater or linear grading operations.  Borrow will be specified by weight, when practical.

Natural Formations

Volume Measurement

When borrow is specified by the cubic yard, measurement may be taken in the borrow pit just as in regular embankment construction.  Use the average end areas.

Only use Department personnel to take measurements of the borrow material.  Contractor's employees may be used to assist in check measurements and measurements of authorized excavations beyond plan lines where the quantity at each location is less than 2,000 cubic yards (yd³) [1,500 cubic meters (m³)].  This assumes that project personnel only are responsible for collecting, plotting, and calculating of the data and quantities.

Weight Measurement

When borrow is specified by cubic yards, weight measurements may be used to calculate the payment quantity:

1.        Take a series of density tests in the borrow areas and average the test results.  This value is the wet density, called WD (lbs/yd³).

2.        Calculate the total weight from the weight tickets.  This value is called W (lbs).

3.        Use the following equation to calculate the payment quantity.

This can be used as a check or if cross-sections are not available.

Other than Natural Formations

Volume Measurement

1.        Take a series of density tests in place and average the test results.  This value is the wet density, called WD (lbs/yd³).

2.        Calculate the total weight from the weight tickets.  This value is called W (lbs).

3.        Use the following equation to calculate the payment quantity:

Weight Measurement for Borrow

When borrow is specified by weight use the following:

1.        Weight tickets minus excess moisture.

2.        Collect weight tickets according to C&MS 109.01.

Adjustment to Borrow Quantity

The quantity of borrow for payment is the measured quantity as detailed above minus:

1.        Suitable excavation wasted.

2.        Excess fill adjusted for shrinkage.

a.        The shrinkage factor used is detailed in Section 203.02, Estimating Shrinkage and Settlement, of this manual.

b.        Use the following equation to calculate the payment quantity:

Payment Quantity = SF × Borrow Quantity

Example: 100,000 CY total borrow, 10,000 CY excess, borrow density is 110 lbs/ft³, and embankment density 120

 lbs/ft³.

Solution:

Shrinkage Factor, SF=110/120= 0.92

100,000 - 0.92 (10,000) = 100,000 – 9,200= 90,800 CY

Explanation:

Borrow was measured at the borrow site.  A larger amount of borrow fit into the embankment.  Density is greater at the embankment location.  Therefore, we subtract less borrow from the final pay.

Be careful about which way you apply the shrinkage factor.

Records

Record all check measurements and check calculations on the appropriate form, date and sign, or initial the form, and place it in the project records.

Records of check measurements must be kept up-to-date at the Project Office during construction and will be reviewed by the Office of Construction Administration during their routine visits to the project.

After completion of the earthwork, prepare a tabulation of earthwork pay items showing plan quantities, where applicable, and listing appropriate measured quantities for all areas where there was deviation from plan lines beyond specified tolerances, which affect the pay quantities, showing total quantities for payment.

This tabulation, together with records of check measurements, constitutes the earthwork report for the project.  After processing, these reports shall be filed in the District Office.

Documentation Requirements - 203 Roadway Excavation and Embankment

1.        Materials.

2.        Verify plan cross-sections.

3.        Cross-sections of borrow site, if required.

4.        Classify suspect soils.

5.        Foundation.

6.        Lifts thickness and roller passes.

7.        Equipment used.

8.        Type of soils.

9.        Take compaction tests according to S-1015.

10.     Benching.

11.     Verify final cross-sections.

12.     Base estimate on yardage from cross-sections, load count or electronic grade control data.

13.     Measure and Pay according to 203.09 and 203.10

14.     Document on CA-EW-1, CA-EW-12 and CA-D-3.  Do not duplicate the information on all forms unless necessary.

204 Subgrade Compaction and Proof Rolling

Importance

Over 25 million dollars of extra work was used to stabilize unstable subgrades during the construction seasons of 2000 and 2001.  This extra work has been minimized in recent years because of the construction and design criteria created since that time.

This section will help the project construct stable subgrades for pavement construction.  Proper subgrade treatment ensures a constructible pavement, enhances pavement performance over its life, and ensures that the pavement design intent is carried through into the construction phase.  This section is based on research performed by the Department from the 1960’s through today.  This section should not be used as the ultimate answer to solve all subgrade problems.

This section is detailed in such a manner so that construction personnel can easily apply information from the field and subsurface investigation to provide reasonable adjustments to the plan subgrade treatment.

Specification and Plan Requirements

Item 204 requires the top 12 inches of the subgrade to be compacted.  Item 204 requires the subgrade to be proof rolled.  If subgrade stabilization or undercutting is designed for the entire project, then proof rolling is only used to verify the stability of the stabilized subgrade.  If special subgrade treatment is provided in the plans at spot locations, proof rolling is specified to identify these areas and then performed afterwards to verify the undercut stability.

Proof rolling deflections and soil conditions that are observed during construction determine if the plan subgrade treatment must be adjusted.  Adjustment of subgrade treatment to fit field conditions is essential and is the responsibility of the Project Engineer.

Subgrade Correction Prior to Proof Rolling

The Engineer must observe the effect of heavy equipment, which operates on the subgrade during rough grading.  When rutting and deflection under heavy equipment indicates unstable subgrade, the Engineer should authorize the correction.  See Elasticity and Deformation of Soils in Section 203.02 of this manual.

Do not delay the correction until it can be checked by proof rolling.  Investigate the extent of the problem by using the Investigation section of this Item.  Be aware that the condition can be improved by time, drainage, and hauling as detailed in the section, Draining and Hauling, of this item.

If needed, make the correction by excavating and disposing of unstable soil and replacing it with suitable material as detailed in the section, Undercut Depth and Stabilization Determination, of this item.

Drainage and Hauling

Excess water in fine-grained soil is the principal cause of unstable soil conditions.  The Engineer has a responsibility to ensure adequate drainage during construction.  If the investigation indicates the need for underdrains or the cleaning of the existing underdrain outlets, the Engineer must order the work as soon as possible. 

Some examples of these conditions are as follows:

1.        Existing underdrains with clogged outlets on rehabilitation projects.

2.        Free water in the subgrade.

3.        Saturated soils of moderately high permeability, such as sandy silt and silty clay of low plasticity. 

4.        Ground water seepage through layers of permeable soil.

5.        Water seeping into test pits.

6.        Water seeping from higher elevations into cut locations.

7.        Water flowing on the top of the rock or shale in subgrade undercuts.

Note: It is difficult to remove water from hard clay soils with PI’s greater than 20 with construction underdrains.

Subgrade stability can be significantly improved by cleaning out the existing underdrain outlets on rehabilitation projects and by adding construction underdrains on new or rehabilitation projects.  Once the underdrain systems are in place and functioning, the drainage system can reduce the subgrade soil moisture content from 3 percent over optimum moisture to the optimum moisture content in 6 to 8 weeks.  Moisture contents that exceed 3 percent over optimum must be dealt with by other means. 

For rehabilitation projects, the Contractor should be instructed to unclog the underdrain outlets immediately.  Try to perform this work in the time frame listed above.  If the project consists of several phases, instruct the Contractor to perform the outlet cleaning for the entire project at the same time. 

For new or rehabilitation projects, subgrade stability can be achieved by constructing the plan or construction underdrains as soon as the water problem is found.  On new construction projects, a longer period of time can be allowed for the underdrain system to work.  Opportune times for this work are at the beginning of construction and before winter shut down.

The plan underdrains should be placed only when they will not be contaminated by further construction.  If contamination is a concern, then sacrificial or construction underdrains should be used on the project.

Item 605 in the C&MS details the construction of construction underdrains. Construction underdrains are usually placed in the centerline of the roadway, but can be placed in other locations too.  They may be placed in the ditch line if water is coming in from a cut section at a higher elevation.  The porous backfill is extended to the subgrade elevation.  The outlets for the construction underdrain are the same pipe material and backfill as regular underdrains.  The underdrains can be outlet to any convenient location, such as catch basins, manholes, pipe, or ditches.  The project should not be concerned with contamination in the upper portion of the underdrain backfill.  Construction underdrains are sacrificial underdrains that will continue to work throughout the life of the contract and afterwards, even though the upper portion is contaminated.

In Figure 204.A, the subgrade is saturated and the soil acts like a waterbed when the subgrade is Proof Rolled or hauled on.  However, once the underdrains are in place and the soil is loaded, as shown in Figure 204.B, then the water has a place to go.  As the soil is loaded or hauled on, the water is squeezed out and the subgrade conditions will improve.

Figure 204.A – Water in the Subgrade without Drainage

Figure 204.B – Water in the Subgrade with Drainage

By placing the drainage system prior to loading or hauling on the subgrade, the water is given a location to escape the subgrade system.  If the drainage system is not in place before hauling or loading, the subgrade will rut or crack and have a detrimental effect on the subgrade and not improve with loading.

Drainage and hauling can work together to correct unstable subgrades under the above given guidelines.

Figure 204.C, Shale and Rock Undercuts, came from Figure 1009-10 in Location & Design Manual – Volume 2, Drainage Design.  The specification requirements are detailed in 204.05.  Shale and rock are cut 24 inches (610 mm) below the bottom of the pavement.  This ensures that the pavement gets uniform support and good drainage.  When rock is blasted and excavated, the resulting surface is very rough and tends to collect water.  Accumulated water will cause some rock and shale to deteriorate. By undercutting the rock, we ensure that any water that collects in the irregular surface does not affect the pavement.  In the past, pavement placed on rock and shale started to develop problems immediately after opening to traffic. 

Figure 204.C – Shale and Rock Undercuts

The underdrains in these rock and shale cuts should extend at least 6 inches (150 mm) into the existing rock or shale formation.  If the underdrains are too high, the water will accumulate at the rock and soil interface and cause subgrade instability.

Construction or rock underdrains can be placed in the ditches and other strategic locations in cut sections to minimize water coming under the pavement.  Water under the pavement without drainage causes the subgrade to act like a waterbed.  With drainage, the conditions improve and become more stable.

When to Proof Roll

For areas where subgrade appears to be stable without undercutting, proof roll after the top 12 inches (305 mm) of the subgrade meets the compaction requirements and after the subgrade has been brought to approximate shape within 0.1 to 0.2 feet (30 to 60 mm) required by plan lines. 

For areas that are obviously unstable and require undercutting, do not proof roll unnecessarily to demonstrate that subgrade correction is required.

The proof rolling should be done immediately after the subgrade compaction operation, when the moisture content of the subgrade soil is near the moisture content that was used to achieve compaction.  This minimizes the subgrade becoming too wet or too dry for an effective proof rolling evaluation.  If the subgrade is too wet, the material will displace and rut.  If the subgrade is too dry, a hard surface crust may carry the proof roller over an undesirable, soft, wet, underlying material without rutting or deflection, and the unstable subgrade may not be detected.

Proof rolling may be done either before or after pipe underdrains are installed.  If done after underdrains are installed, rolling should not be done directly over the underdrains.  In C&MS 204.06, proof rolling must be performed at least 1.5 feet (0.5 m) away from the underdrains because of the potential damage to the underdrains. 

Proof Rolling (204.06)

CA-EW-2 Proof Rolling Documentation Form is used to document the proof rolling operation.  It is imperative that the stations, deflections, weight of the proof roller, and comments are well documented.  Digital photographs of subgrade distress are highly recommended.

The primary purposes of proof rolling are to locate unstable areas, check the subgrade compaction, to carry out the intent of the design, and to provide uniform support for the pavement structure.  Unstable subgrade areas that are located will be corrected so that the subgrade density can be maintained throughout the construction.  If done correctly, the pavement design intent will be carried through the construction process.

One trip with a proof roller is adequate to achieve satisfactory proof rolling results. 

An over loaded proof roller for a soil type may cause satisfactory subgrade to become unstable during proof rolling.  Conversely, unstable areas will not be found if the proof roller is too light for the soil type.

Selection of Proof Roller Weights and Tire Pressure

In view of the many variations which must be expected in Ohio soil and moisture conditions, the Engineer is given authority to vary the weight and tire pressure of the proof roller to fit the conditions.  The weights and tire pressures for the different soils are detailed in C&MS 204.06.

It is imperative that the project chooses the correct load for the type of soil on the project.  These loads and tire pressures are soil type sensitive when evaluating the subgrade.  For A-3, A-4, A-6, and A-7 soils use a 35 ton (32 metric ton) roller with a tire pressure of 120 psi (820 kPa).  This load and tire pressure is used on most projects because these are the most common soils found in the State of Ohio.

For granular soils and soil, rock, and granular mixtures, use a 50 ton (46 metric ton) roller with 120 psi (820 kPa) tire pressure.  However, if the granular material was placed as part of an undercut to stabilize an unstable subgrade, then use the weight appropriate for the original subgrade materials (35 tons).

The goal of proof rolling is to maximize the load to locate unstable subgrade.  These unstable soils could be 3 to 5 feet (1 to 2 m) deep.  In rare cases, the unstable soil may be deeper than 5 feet (2 m).

Close inspection throughout proof rolling is necessary to observe the rolling effects and to mark unstable subgrade locations for correction or investigation.  Inadequate stability is indicated by deflection, cracking, or rutting of the surface of the subgrade.

Failure Criteria

When is rutting from the proof roller an indication of unstable subgrade? Technically, the maximum allowable rutting or elastic movement of the subgrade is the amount that allows the subgrade soil to maintain the specified density throughout the construction process.  For example, if subgrade density can be maintained with 6-inch ruts, then this would be the allowable maximum. In practice, when the ruts from the proof roller are deeper than 1 inch, then there is usually cause for concern.  Additionally, if the subgrade deflects more than 1 inch with substantial cracking or lateral movement of the soil, then this is also cause for concern.  Elastic deflection is when the subgrade moves down under the weight of the proof roller and then comes backup (rebounds) after the proof roller passes.

When rutting and deflections are less than 1 inch, there is no assurance that overlying pavement construction will not damage the subgrade compaction.  Although subgrade density and stability can be maintained during proof rolling, the repetitive loading, the hauling of materials, and the base and pavement construction can still destroy the subgrade compaction.  This may be an issue on some reconstruction projects.  On reconstruction projects, the following complications can create or worsen subgrade problems.  

1.        Water accumulates under the pavement because of poor drainage or clogged underdrain outlets. 

2.        Construction time frames are limited.

3.        Space limits the ability to dry the material in place. 

4.        Once the pavement is removed, all the drainage is toward the subgrade.  This compounds an already poor drainage situation.

5.        Alternate haul routes are limited or not available on rehabilitation projects.

The failure criteria are used in this section to determine the locations from which to perform a detailed analysis.  This detailed analysis consists of methods discussed later in this section, such as rut depth, soil borings, and test pits.  If the subgrade deflects beyond the failure limits given in this section, and the soil borings and test pits determine that the subgrade does not need to be undercut, then the subgrade should be considered satisfactory.  One additional area to evaluate is the moisture content of the soil.  Some soils are more prone to rut at moisture contents greater than 3 percent below the optimum moisture content.  In fill locations, the moisture content can be reduced to minimize this problem.  If all of the above criteria are met, there is no reason the subgrade should not perform as anticipated.  If there is any debate between the Department and the Contractor, especially if a warranty is involved, then further nondestructive or destructive testing can be used to resolve the issue. 

In Figure 204.D, the soil has been compacted in the top foot of the subgrade and the conditions are good for the top 3 feet (1.0 m).  However, there is a soft layer at a lower elevation.  The soft layer has no detrimental effect on the subgrade density during the subgrade compaction.

Figure 204.D – Stage 1 Compaction of Subgrade

In Figure 204.E the proof roller deflects because of the soft soils. The subgrade density may or may not be affected by the proof rolling.  The loss of subgrade density is proportional to the amount of rutting or elasticity during proof rolling and subsequent construction operations.  The severity of the overall subgrade condition can be measured by the amount of the deflection and elasticity on the surface.

Figure 204.E – Stage 2 Proof Rolling

When the proof rolling deflections exceed the failure criteria; the proof rolling, repetitive loading, and pavement construction can destroy the top layers of the aggregate base and subgrade.

In actual field conditions, this soft layer can be just a few inches thick and at any elevation from the top 1 foot (0.3 m) to as deep as 5 feet (2 m).  In addition, it may be an indication of an overall soil condition that is just over optimum for the entire 5 foot (2 m) depth of the subgrade.  The test pit excavation is used to identify the layer, or layers, causing the surface distress. This is further detailed in the section, Investigation, of this Item.  It is imperative that these conditions are correctly identified.

Crusting is a condition when the subgrade surface appears to be dry and there is substantial cracking on the surface with or without rutting.  This indicates a need for further investigation and usually indicates soft or wet underlying soil at depth with the top foot or so of the subgrade being very dry.

Variations in the Proof Rolling Results

You should not be too concerned with occasional or nominal deflections in excess of the above failure criteria.  If the density is checked, and the investigation shows that good soil extends throughout the top 5 feet of the subgrade, then the design intent will be fulfilled and the project can be constructed.  All soils will occasionally deflect under these loads. 

The pavement design is based on an average CBR.  The CBR value was directly correlated to soil density many years ago.  By using the average CBR (Density) value, the pavement design accounts for a 30 percent, or one standard deviation variation, in the subgrade strength from the design CBR. Fifteen percent is expected to exceed this value and 15 percent is expected to be less than this value.  Some variation in the subgrade condition is already accounted for in the pavement design.

Another consideration is the fact that these proof rolling loads and tire pressures are about 10 times the final in-place stresses once the pavement is constructed.  The proof rolling tire pressures are between 120 to 150 psi (820 to 1030 kPa) and the stresses, once the pavement is constructed, are about 8 psi (55 kPa) for a thin asphalt pavement and 4 psi (27 kPa) for a thick concrete pavement.  These loads are the largest loads that the subgrade will encounter. 

If the project can be constructed while maintaining subgrade density, the subgrade design intent will be fulfilled.

The project should not be concerned with the “Pavement Warranty” issues that Contractors often bring up.  If the project follows these guidelines, and properly documents the subgrade work, Central Office can defend the warranty issue.

Once failure is established based on the proof rolling results, the responsibility for the correction of the failure should be determined.

Responsibility for the Unstable Subgrade

If unstable subgrade locations are found, take compaction tests to determine if the specifications are met in the top 12 inches (300 mm).  The Engineer should instruct the Contractor to correct any deficiencies found in these locations.

The Department is responsible when the unstable subgrade is encountered in:

1.        Cuts.

2.        On reconstruction projects.

3.        In shallow fill locations where the unstable material is found under the contract fill.

4.        When the unstable material is found at lower elevations than the project contract work.

Subgrade stability may not be possible by compacting the upper 12 inches (0.3 m) because of conditions at these lower elevations. 

It is the Contractor’s responsibility to correct all unstable locations in fills.  If the Contractor built the fill correctly, the proof rolling will do nothing but verify specification work.  If the fill fails then the proof rolling will determine the location of the deficient specification work. 

If the Contractor fails to maintain the subgrade, the Engineer should instruct the Contractor to repair the failed areas.  See C&MS 203.04.A for the Contractor’s responsibility to drain and maintain the subgrade. 

The Contractor must be afforded reasonable use of the subgrade for hauling and for constructing the base material.  If subgrade density cannot be maintained through reasonable use of the subgrade, then the allowable proof rolling rutting is too much.  If the project conditions allows, areas other than the subgrade should be used as haul roads.  For a Contractor ‘to bid’ to haul loaded trucks or scrappers endlessly across the subgrade throughout the life of the project is not reasonable.  At a minimum, the Contractor should be allowed the use of the subgrade to place the base material with vehicles of legal weight.

Investigation

Investigate the causes of failed locations quickly to expedite the corrective treatment.  Three pieces of information are needed to make the most economical subgrade treatment:

1.        Rut depth.

2.        Soil boring information.

3.        Test pit data.

At this point, the rut depth has already been determined.

Soil Boring Information

For rehabilitation projects or cut sections, the soil borings can be examined to determine an estimated undercut depth or stabilization methods.

Evaluate Standard Penetration Test (SPT) results from soil borings in the failed subgrade locations.  The Standard Penetration Test (SPT) is an indicator of soil consistency or strength and measures the number of blows per foot (N) required to drive the soil sampler through the soil.  The soil data on the boring logs are presented as the number of blows required to drive each 6-inch (150 mm) increment.  The first 6 inches (150 mm) of the run is ignored because the sampler may not be seated in the borehole or may be driven through cuttings.  For example, standard penetration data shown as 1/2/3 has an N value of five blows per foot.

When investigating the need for undercutting or stabilization in failed locations, look at the borings in those locations in the upper 5 feet (1.5 m) of the subgrade.  At each location, pick the lowest N value when multiple N values are taken in the top 5 feet (1.5 m) of subgrade.

Average the N value along the failed locations.  This value provides one part of the information needed to determine the undercut depth or stabilization methods.

Test Pits

Once the soil borings have been evaluated, construct test pits by excavating 3 to 5 feet (0.6 to 1.5 meter) into the subgrade using the Contractor’s excavation equipment.  Excavate at least two test pits that represent the failed area.  Use judgment for long areas, usually about two to four test pits per mile is sufficient.  Construct the test pits across the width of the subgrade in the failed locations.  Pick locations with the highest deflections to evaluate the most severe locations. 

Warning: These trenches may collapse on the construction personnel.  The Department offers an 8-Hour Construction Safety Class to evaluate the trench collapse risk.  In addition, there is a trench safety class offered by the Bureau of Workers Compensation, Division of Safety and Hygiene.  These classes are given statewide, all year around.  (614-466-5563)

An examination of the soil and moisture conditions in these test pits provides valuable information to make the appropriate correction.  Once the pits are excavated, the Engineer must examine the trench sidewalls and the bottom of the cut.

Record the test pit information on CA-EW-3 Subgrade Test Pit Investigation form shown in Figure 204.G.  The soil conditions vary with depth and must be quantified.  By examining the sidewalls, the Engineer can determine the soil type, layer thickness, soil condition, and soil strength by using a hand penetrometer.

Figure 204.F – Form CA-EW-3 Subgrade Test Pit Investigation

The Engineer must field classify the soil.  See 203.02 Materials, Identifying Soil and Granular Materials in the Field, for help in the classification.

Added soil conditions are described on the bottom of the test pit form.  These conditions are stated in commonly-known consistencies, so that the non-geotechnical reader can relate to the soil conditions.  They are listed on the bottom of the form.  No explanation is needed for these terms.

Hand Penetrometer Readings

A hand penetrometer can be used to further classify the soil and to estimate its strength.  A hand penetrometer can be obtained from a test lab supply company for less than $100.  Hand penetrometers can be obtained from the following companies:

Gilson

Model # HM-500

ELE

Model # E129-3729

Humboldt

Model H-4200

The exact instructions come with the hand penetrometer.  In summary:

1.        Push the hand penetrometer slowly into the soil perpendicular to the surface.

2.        Record the reading when the hand penetrometer penetrates the soil to the 1/4-inch groove mark.

3.        Record the readings to the nearest 0.25 tons per square foot (tsf).

4.        Take at least three different readings in each soil layer.

Use the CA-EW-3 Subgrade Test Pit Investigation form to record the readings.  Average the readings once three readings are taken for the soil layer.  Also, evaluate the bottom of the test pit; this is extremely valuable information.  Average the hand penetrometer readings (HP) of all the test pits in the failed locations.  Use this number to further evaluate the undercut depth or stabilization methods.

Consider the following when evaluating the sidewalls of a trench:

1.        Different layers of a natural formation or cut are more noticeable than fill materials.

2.        High hand penetrometer readings may be obtained with high deflections or rolling at the surface. This is an indication of soft soil at a lower elevation than 5 feet (2 m) or a subgrade soil that is just too wet.

Undercut Depth and Stabilization Determination

Once the proof rolling rut depth (in inches), soil boring information (N), and hand penetrometer readings from the test pits (HP) are obtained, use the Subgrade Treatment Chart in Figure 204.H to determine the recommended depth of undercut or chemical stabilization.  The input values (rut depth, N and HP) are on the horizontal axis.  The two curves show the undercut depth with a geotextile and with a geogrid. The chart also shows the stabilization depth required in inches along the bottom.  Note that the results from this chart are guidelines. The subgrade conditions might require undercuts that are less than or greater than those shown, because subgrade conditions can be highly variable.

Figure 204.G – Subgrade Treatment Chart

The subgrade treatment chart takes into account some variation in test results, the anticipated loading from the proof roller, and typical truck loading during construction.

Use the rut depth, N values, and hand penetrometer readings (HP) to draw a vertical line to the curve.  The recommended depth of the undercut is where the vertical line intersects the curve.  For soft and very soft soils, it may be economical to use a geogrid to reduce the depth of the undercut.  The geogrid restrains the granular material from lateral movement and makes it more effective.  Refer to Supplemental Specification 861 for using geogrids for subgrade stabilization.

The chart does not recommend chemical stabilization for soft and very soft soil.  This is primarily because of constructability problems.  Although chemical stabilization does improve the stability of soft and very soft soils, these soils usually cannot support the equipment used to perform the chemical stabilization. 

It would be rare to see a perfect alignment in the results from all three inputs.  In some cases, one or two of these inputs may not be available.  In other cases, some judgment is needed to redesign the most economical undercut that will work.  In order of hierarchy, use the test pit data, then the N values, and then the rut depth.  The rut depth is the least reliable indicator of undercut need because it cannot determine which soil layer is causing the deflection.

There will be cases where the N values and unconfined values are all high, but the subgrade is rolling and cracking, and rut depth is greater than allowable.  In this case, use the rut depth as a guide to redesign the undercut.  See the last example in the example section.

There is an example in Figure 204.I.

Given:     Average N value was 10.       
Average HP= 1.5 tsf.                    
Average Rut Depth was 2 to 4 inches.

Answer:  Use an undercut depth of 12 to 18 inches with a geotextile or chemically stabilize with 12 to 14 inches of cement or lime.  For very large areas, give serious consideration to the stabilization method.  It will be more cost effective.

Figure 204.H – Example using the Subgrade Treatment Chart

After making the undercut, this depth may need to be adjusted to meet the actual conditions.  See the section, “Implementation during Construction,” of this manual.

General Rules

On new construction projects, if all of the unstable material can be removed, and the bottom of the test pits or cuts are stable, then soil may be used as replacement material.  For reconstruction projects, soil is usually not available in large quantities.  Therefore, soil undercuts are less effective solutions on reconstruction projects.

If the bottom of the test pit is unstable when conditions are highly variable or for rehabilitation projects, use granular material, rock, geotextile, geogrid, or chemical stabilization rather than soil.

Undercuts should be used in small locations or in areas where spot locations are identified.  Consider chemical stabilization for long areas greater than one mile.

Only the most unusual cases require removal to depths greater than 3 feet (1 meter).  Seventy five to 90 percent of subgrade problems can be solved with a 1 foot treatment of granular material and geotextile or chemical stabilization.

If a project or section of a project undercut locations are more than 30 percent of the total area, undercut or chemically stabilize the entire area.  If you do not undercut the entire area, these locations will grow, and the construction will be inefficient as the construction proceeds. The Department pays a higher cost at a reduced, final quality by undercutting a high percentage of the subgrade throughout the project.  ODOT would not repair a bridge deck or pavement with this high a percentage of repairs.

Chemical stabilization methods speed construction because of the ability to work immediately after a rain.  Estimates indicate that the construction production is increased by at least 50 percent by using stabilization methods.

Examples:

The following table shows some example solutions.  The types of material refer to 703.16.C and Item 206.

Given

Solution

Project with Silty A-4a material with N=15 or HP=2.0 tsf

Rut Depth>1"

12 inches of Granular Material Type B, C or D with geotextile or 12 inches of stabilization with cement

Project with Deep, weak, and wet A-4a with N = 12 or HP=1.4 tsf

Rut Depth = 2"

18 inches of Granular Material Type B, C, or D, with geotextile or 12-14 inches of stabilization with  cement

New Construction,  Deep, weak & wet A-4a, A-6 or A-7-6 combination with N = 10 or HP=1.0tsf.  Rut Depth = 4"

18 inches of Granular Material Type B  C or D with geotextile or 14 inches of stabilization with lime or cement. (Check the PI of the soils. Use the stabilization type according to the PI’s of the  soil.) 

New Construction Jell-O like consistency soil with N = 5 or HP=0.5 tsf.  Rut depth > 6"

30 inches of Granular Material Type B, C, or D, with geotextile, or 18 inches of granular material with geogrid and geotextile,  or 16 inches of chemical stabilization. ( Check the PI of the soil.)

Any  Project with soup like consistency soil  with N = 2  or HP=0.25 tsf

Rut Depth = Buried equipment

 4 feet of Granular Material Type B, C, or D, with geotextile, or 3 feet of granular material with geogrid and geotextile.  (Use type D Granular Material if available)

Reconstruction Project Sandy, A-4a, A-6a soil, PI < 20, N = 8 or HP=1.0 tsf

Rut Depth = 6". (Long Project)

Cement Stabilized Subgrade

14" deep at 6%

New construction A-7-6 clay soil, PI > 20

N = 11 or HP=1.2 tsf

Rut Depth =3".  (Long Project)

Lime Stabilized Subgrade

12" deep at 5%

Reconstruction Project A-6a silty clay

PI < 20, N=30 and HP>4.5 tsf

Rut depth > 2" and rolling

The key here is the rolling. Probably caused by high moisture content of the soil at a depth.  If the subgrade is rolling with one pass of a proof roller then the subgrade condition can rapidly deteriorate during construction.

16" of Cement at 6% or

 2.5 foot undercut with Granular Material Type B, C, or D, with geogrid and geotextile.

Use Type D material if available.

Type of Undercut Materials

Use Granular Material Types B, C, D, E, and F.  They are generally cheaper than 304.

Type B is a well-graded aggregate with the gradations of Items 304, 411, or 617.  Type C has a top size of 3 inches and type D has a top size of 8 inches.  Both C and D are well-graded materials.  The larger top size material will bridge the unstable material better than the smaller size material.

Use Granular Material Type E when water levels are high or cannot be drained.  The Type E materials are very porous.  Always choke the Granular Material Type E with Granular Material Type B or geotextile fabric.

There is a potential for piping of soil into the Granular Material Type E as shown in Figure 204.J.  In the figure on the left, when the open graded material is placed on wet, fine-grained soil, the soil pipes into the open graded material during construction.  In the figure on the right, the geotextile fabric blocks the fine-grained soil from entering the open graded material.  Geogrids will not perform this separation function.

Figure 204.I – Soil Piping in Open Material

Underdrains cannot be placed through Granular Material Types D, E, or F.  Use Granular Material Type B in the locations of underdrains.  Underdrains can be trenched through geotextile and geogrid if there is enough material above the geotextile or geogrid to confine it.  Always drain the undercut to an underdrain, catch basin, or pipe.

The use of 712.09 Geotextile Fabric Type D is recommended in most cases.  The cost is around $1.00 per square yard, and it serves to keep the granular material and underlying soil separated. This results in better performance of the undercut.  When the depth of the undercut is 24 inches or greater, consider using a geogrid to reduce the depth of the undercut.  For undercuts 12 to 16 inches deep, place a geotextile in the bottom, then the geogrid, and then the granular material.  For undercuts 16 inches deep and greater, place the geotextile in the bottom, then half the granular material, the geogrid, and then the rest of the granular material.  For severe situations, you can use multiple layers of geotextile and geogrids.  Consult with the Office of Geotechnical Engineering in these cases.

Chemical Stabilization of the Subgrade

Item 206 Chemically Stabilized Subgrade can be used to treat unstable subgrades.  Lime or cement is typically used, but lime kiln dust is another option.

Lime is used for A-6b (silty/clay) or A-7-6 (clay) soils which have a plasticity index of 20 or greater. As a general guideline, use 5 percent lime by dry weight of the soil, assuming a dry weight of 110 pounds per cubic foot. 

Cement can be used to treat unstable subgrades consisting of A-3 (fine sand, coarse and fine sand), A-2-4 through 7 (gravels), A-4a (sand silt), A-6a (silt and clay), A-6b (silty clay), or A-7-6 (clay) which have a plasticity index less than 20.  As a general guideline, use 6 percent cement by dry weight of the soil assuming a dry weight of 110 pounds per cubic foot. 

Lime kiln dust can be used for soils which have a plasticity index in the range of 10 to 20. Consult with the Office of Geotechnical Engineering when using lime kiln dust.

See Item 206, Chemically Stabilized Subgrade, of this manual.

Implementation during Construction

Once the type of stabilization treatment has been chosen, constant monitoring of the construction is required to adjust the treatment to meet the field conditions.  Soil conditions always vary; they vary the most on rehabilitation projects or in cuts.

If the undercut option is chosen, the project should monitor the bottom of the cut and evaluate the condition.  Take hand penetrometer readings at the bottom of the cuts and compare them to the initial test pit or soil boring information.  If the condition changes from the earlier evaluation of the test pits or the soil borings, then adjustments to the undercut depth are required.

For undercuts that are 2 feet deep or greater, give consideration to using geogrid in addition to the geotextile fabric.  The need for geogrid can be determined by placing approximately half of the undercut depth.  Load the undercut with a fully loaded truck.  If the area is unstable, place the geogrid and continue to fill the undercut.

Once the undercut or stabilization is complete, proof roll the area to ensure that the final subgrade meets the rut depth and density requirements as detailed earlier in section “Failure Criteria.”

Constant vigilance is needed in order to make the most economical correction.  It is easy to over-excavate unnecessarily and waste money.  It is more difficult to make the right economical choice to stabilize the subgrade and to meet the design and construction needs.

Documentation Requirements - 204 Subgrade Compaction and Proof Rolling

1.        Materials.

2.        Compaction according to S-1015.

3.        Lift thickness and roller passes.

4.        Equipment used.

5.        Type of soils.

6.        Verify square yardage.

7.        Verify subgrade line and grade.

8.        Proof roll and make corrections.

9.        Subgrade Test Pit Investigations.

10.     Undercut measurements.

11.     Document on CA-EW-1,CA-EW-2,CA-EW-3, CA-EW-8, CA-EW-12 and CA-D-3.  Do not duplicate the information on all forms unless necessary.

205 Chemically Stabilized Embankment

Uses of Chemically Stabilized Embankment

Chemically stabilized embankment is generally used to repair landslides, as shown in the following figure.  This situation involves the removal of wet soil, treating it with cement, lime, or lime kiln dust, and then using the treated soil to rebuild the embankment.  Notice the addition of drainage to the slide repair.

Figure 205.A – Typical Use of Chemically Stabilized Embankment to Repair Landslide

Cement is most effective in treating soils with a Plasticity Index (PI) less than 20, such as sandy and silty soils like A-3a, A-4a, A-4b, A-6a, and some A-6b soils.  Use cement stabilized subgrade to treat areas with N values (SPT blow counts) as low as 5 and unconfined strengths (hand penetrometer) as low as 0.5 tsf.

Lime is most effective in treating soils with a PI greater than 20, such as A-7-6 and A-6b soils.  Use lime stabilized subgrade to treat areas with N values (SPT blow counts) as low as 10 and unconfined strengths (hand penetrometer) as low as 1.0 tsf.

Lime kiln dust (LKD) may be used to stabilize unstable subgrade soils which have a PI from 10 to 20.  Consult the Office of Geotechnical Engineering when using LKD.

Materials (205.02)

If using cement, use Type 1 cement according to 701.04.  If using lime, use quick lime conforming to 712.04.B.  Quick lime must pass through the No. 4 (4.75 mm) sieve.  Lime must come from a certified supplier.

Lime kiln dust is another material that can be used for soil stabilization.  The Department has begun using lime kiln dust for soil stabilization on some projects, but it is generally not included in the plans.  However, the Contractor may propose to use it in a value engineering change proposal. Lime kiln dust must conform to 712.04.C.

Construction (205.04)

Limitations

Chemical stabilization should not be performed when the temperature is below 40 ºF (5 ºC) or when the ground is frozen.  In order to stabilize the soil, the chemical needs to react with the water in the soil.  It cannot do that if the water is frozen.  If it is raining, the free water will react with the lime or cement instead of the water in the soil.

Spreading lime, cement, and lime kiln dust creates some dust; therefore, chemical stabilization should not be performed when it is windy, as this will spread the dust outside of the project area.

Spreading (205.04.A)

The amount of chemical applied to each lift is based on a percentage of the dry weight of the soil that will be treated.  The percentage is typically 4 to 10 percent for cement and 4 to 8 percent for lime.  If the Mixture Design for Chemically Stabilized Soils pay item is included in the plans, the Contractor will determine the appropriate percentage of chemical based on a testing program.  If the pay item for the mixture design is not included in the plans, use the percentage given in the plans or the percentage given in 205.04.A.

To calculate the spreading rate (number of pounds of chemical per square yard), use the following equation:

C = 0.75 × T × D × P

Where:

C = Spreading rate for chemical (pounds per square yard).

T = Thickness of embankment lift (inches).

D = Average dry density of soil (if not known, assume 110 lb/ft³).

P = Percentage of chemical, expressed as a decimal

       (e.g., 5% = 0.05)

0.75 is a unit conversion factor (9 ft² / 1 yd² × 1 ft / 12 in).

For example, if using 4 percent of a chemical and an 8-inch embankment lift:

C = 0.75 × 8 in × 110 lb/ft3 × 0.04 = 26.4 lb/yd² of chemical

The Contractor must submit a spreading plan or report two days before the work and indicate how the Contractor will achieve the required spreading rate.  After the spreading operation, check the Contractor’s spreading rate by taking the total weight of chemical spread and dividing it by the area that was treated.

For slide repair work, a loader is sometimes used to spread the chemicals.  The exact amount of chemical in each lift of soil is not as critical as it is in subgrade stabilization work.

When a mechanical spreader is used, dusting is minimized by using a shroud around the spreader bar that extends to the surface.  A distribution bar with a maximum height of 3 feet (1 m) above the subgrade can be used.  The chemical should not be spread if wind conditions are such that blowing dust exceeds the limits in 107.19.

Figure 205.B – Spreading Cement with a Shroud around the Spreader Bar

Mixing (205.04.B)

The Contractor should mix the chemical into the soil immediately after spreading the chemical.  The Contractor may use a spring tooth harrow, a disk harrow, or a power driven rotary mixer which looks like a big rotary tiller.  However, if the area is beneath a pavement or paved shoulder, the Contractor must use the power driven rotary mixer.

Figure 205.C – Rotary Mixer for Chemical Stabilization

If using a power driven rotary mixer, mix the soil and chemical until all the soil clods are reduced to a maximum size of 2 inches (50 mm).  Add water, if necessary, to bring the mixture to at least the optimum moisture content if using cement or lime kiln dust and bring the mixture to at least 3 percent above optimum moisture content if using lime.  Quick lime reacts more strongly with water and the additional water prevents future expansion problems.  Determine the optimum moisture content from the moisture-density curves developed in the test program from the mixture design or by using the Ohio Typical Moisture Density Curves and the one-point Proctor method in Supplement 1015.

Figure 205.D – Disk Harrow

If using a spring tooth or disk harrow, break-up the soil with the harrow before spreading the chemical.  Mix the chemical into the soil and add water as described above.  During mixing, use at least 20 passes of the harrow: 10 in one direction and 10 in a direction which will be perpendicular to the first 10.  Reduce all the soil clods to a maximum size of 1 inch (25 mm).  The harrows do not mix the chemical as well as the rotary mixer; therefore, more effort is required with the harrow to mix the chemical and soil.

Note that for Chemically Stabilized Embankment, the mixing is the same for all the chemicals.  This is different from Chemically Stabilized Subgrade.

Compacting (205.04.C)

Compact to 98 percent of the maximum dry density and use the one-point Proctor method in Supplement 1015 to determine the maximum dry density.  In some cases, the test section method or the moisture-density curves developed by the Contractor may be used to determine the maximum dry density.

Mixture Design for Chemically Stabilized Soils (205.05)

If a pay item for Mixture Design for Chemically Stabilized Soils is included in the plans, then the Contractor uses the testing program described in Supplement 1120 to determine the spreading rate for the chemical.  Different mixtures of the soil and chemical are tested for unconfined compressive strength.  The results are used to determine the percentage of chemical used in the field.  The common increase in strength ranges from 20 psi to 100 psi with lime and from 50 psi to 200 psi with cement.

Method of Measurement (205.06)

The mixture design pay item also includes verification testing of the stabilized subgrade. For this reason, the Department pays for only two-thirds of the lump sum item for mixture design testing after the mixture design is complete.  The other one-third is paid after the chemically stabilized subgrade is completed.

Documentation Requirements - 205 Chemically Stabilized Embankment

1.        Materials per 205.02.

2.        Check spreading rate for lime, cement, or lime kiln dust.

3.        Verify cross-sections.

4.        Temperature must be 40 °F (4 °C) or above and the soil cannot be frozen.

5.        Document the construction: spreading, mixing, and compaction.

6.        Perform the compaction testing according to Supplement 1015.

7.        Measure and pay according to 205.06 and 205.07.

8.        Final cross-sections.

9.        Document on CA-EW-1, CA-EW-12 and CA-D-1, and CA-D-3.  Do not duplicate the information on all forms unless necessary.

206 Chemically Stabilized Subgrade

Uses and Application for Chemically Stabilized Subgrade

Use chemically stabilized subgrade for improving long sections of subgrade, generally more than a mile.  It is not cost-effective for short spot locations.  If the chemical stabilization is not in the plans, and is being added to the project in order to address a subgrade problem, use the Subgrade Treatment Chart in Figure 204.H to determine the appropriate depth of chemical stabilization.  If the chemical stabilization is in the plans, the designer used Geotechnical Bulletin 1, Plan Subgrades, from the Office of Geotechnical Engineering to design the chemical stabilization.

There are primarily two types of chemicals used to treat soil: cement and lime.  Recently, the Department has also started using lime kiln dust.

Cement is most effective in treating soils with a plasticity index (PI) less than 20, such as sandy and silty soils like A-3a, A-4a, A-4b, A-6a, and some A-6b soils.  Use cement stabilized subgrade to treat areas with N values (SPT blow counts) as low as 5, unconfined strengths (hand penetrometer) as low as 0.5 tsf, and to remove ruts up to 12 inches (300 mm) deep.

Lime is most effective in treating soils with a PI greater than 20, such as A-7-6 and A-6b soils.  Use lime stabilized subgrade to treat areas with N values (SPT blow counts) as low as 10, unconfined strengths (hand penetrometer) as low as 1.0 tsf, and to remove ruts up to 6 inches (150 mm) deep.

Lime kiln dust (LKD) may be used to stabilize unstable subgrade soils which have a PI from 10 to 20.  Consult the Office of Geotechnical Engineering when using LKD.

Materials (206.02)

If using cement, use Type 1 cement according to 701.04.  If using lime, use quick lime conforming to 712.04.B.  Quick lime must pass through the No. 4 (4.75 mm) sieve.  Lime must come from a certified supplier.

Lime kiln dust is another material that can be used for soil stabilization.  The Department has begun using lime kiln dust for soil stabilization on some projects, but it is generally not included in the plans.  However, the Contractor may propose to use it in a value engineering change proposal. Lime kiln dust must conform to 712.04.C.

The curing coat can consist of a rapid setting, emulsified asphalt, prime coat or a curing compound.  The prime coat may be specified by plan note to discourage traffic on the subgrade during the curing period.  The prime coat remains tacky, so equipment operators tend to stay off of it.

Test Rolling (206.04)

If chemical stabilization is specified in spot locations, use test rolling with a proof roller to locate areas that require the chemical stabilization.  If rutting is significant (greater than 6 inches for cement, greater than 4 inches for lime), investigate the subgrade by digging test pits.  After the chemical stabilization is complete, proof roll the stabilized areas.

If chemical stabilization is specified throughout the project, do not test roll before stabilization, but do perform proof rolling after the chemical stabilization work is complete.

Construction (206.05)

Limitation

Chemical stabilization should not be performed when the temperature is below 40 ºF (5 ºC) or the ground is frozen.  In order to stabilize the soil, the chemical needs to react with the water in the soil.  It cannot do that if the water is frozen.  If it is raining, the free water will react with the lime or cement instead of the water in the soil.

Spreading lime, cement, and lime kiln dust creates some dust; therefore, chemical stabilization should not be performed when it is windy, as this will spread the dust outside of the project area.

Spreading (206.05.A)

The amount of chemical applied to the subgrade is based on a percentage of the dry weight of the soil that will be treated.  The percentage is typically 4 to 10 percent for cement and 4 to 8 percent for lime.  If the Mixture Design for Chemically Stabilized Soils pay item is included in the plans, the Contractor will determine the appropriate percentage of chemical based on a testing program.  If the pay item for the mixture design is not included in the plans, use the percentage given in the plans or the percentage given in 206.05.

To calculate the spreading rate (number of pounds of chemical per square yard), use the following equation:

C = 0.75 × T × D × P

Where:

C = Spreading rate for chemical (pounds per square yard).

T = Thickness (or depth) of stabilization (inches).

D = Average dry density of soil (if not known, assume 110 lb/ft³).

P = Percentage of chemical, expressed as a decimal.
      (e.g., 5% = 0.05)

0.75 is a unit conversion factor (9 ft² / 1 yd² × 1 ft / 12 in).

For example, if using 5 percent of a chemical and a 12-inch depth of treatment:

C = 0.75 × 12 in × 110 lb/ft3 × 0.05 = 49.5 lb/yd² of chemical.

The Contractor must submit a spreading plan or report 2 days before the work and indicate how the Contractor will achieve the required spreading rate. After the spreading operation, check the Contractor’s spreading rate by taking the total weight of chemical spread and dividing it by the area that was treated.  To check the spreading rate during the work, take a pan and place it on the prepared surface in front of the spreading truck (the pan will have to be placed in a small depression to keep the shroud from knocking it over).  Once the spreader has passed and filled the pan with the chemical, weigh the filled pan.  Determine the weight of the chemical by subtracting the weight of the pan.  Calculate the spreading rate by dividing the weight of the chemical by the area of the pan (remember to convert the area of the pan to square yards).

Example:                 Weight of pan and chemical = 7.3 lb

                                Weight of pan = 2.8 lb

                                Pan is 9 in × 13 in

When a mechanical spreader is used, dusting is minimized by using a shroud around the spreader bar that extends to the surface.  A distribution bar with a maximum height of 3 feet (1 m) above the subgrade can be used.  The chemical should not be spread if wind conditions are such that blowing dust exceeds the limits in 107.19.

Figure 206.A – Spreading Cement with a Shroud around the Spreader Bar

Mixing (206.05.B)

The Contractor should mix the chemical into the soil immediately after spreading the chemical.  The specifications require a power driven rotary mixer which looks like a big rotary tiller.

Mixing Cement and Lime Kiln Dust

The specification describes a two-step process for mixing cement or lime kiln dust into the soil, but a single mixing is allowed if the Contractor can add water through the mixer and obtain the required gradation with the single mixing.  For cement and lime kiln dust, at least 80 percent of the mixed soil must be smaller than the openings in a No. 4 sieve, and all of the soil clods must be smaller than 1 inch (25 mm).  Any stones in the soil that would be retained on the No. 4 sieve are not considered when calculating the percentage.  If necessary, add water until the soil-chemical mixture is at optimum moisture content.  Determine the optimum moisture content from the moisture-density curves developed in the test program from the mixture design or by using the Ohio Typical Moisture Density Curves and the one-point Proctor method in Supplement 1015.  To ensure thorough mixing, check the mixture for uniform color.

Figure 206.B – Rotary Mixer for Chemical Stabilization

Mixing Lime

Lime stabilization requires two separate mixings with a mellowing period in between the mixings.  During the initial mixing, all the soil clods are reduced to a maximum size of 2 inches (50 mm) and water is added, if necessary, to bring the mixture to at least 3 percent above optimum moisture content.  Quick lime reacts more strongly with water and the additional water prevents future expansion problems.  Determine the optimum moisture content from the moisture-density curves developed in the test program from the mixture design or by using the Ohio Typical Moisture Density Curves and the one-point Proctor method in Supplement 1015.

After the initial mixing, lime stabilized subgrade is allowed to sit undisturbed (mellowed) for at least 24 hours, but not more than 7 days.  During the mellowing period, the clumps of lime breakdown and the lime reacts with the soil, breaking up the soil clods.  After the second mixing, at least 60 percent of the mixed soil must be smaller than the openings in a No. 4 sieve and all of the soil clods must be smaller than 1 inch (25 mm). Any stones in the soil that would be retained on the No. 4 sieve are not considered when calculating the percentage.  To ensure thorough mixing, check the mixture for uniform color.

Compacting (206.05.C)

Chemically stabilized subgrade should be compacted immediately after the shaping and final mixing.  For cement, the compaction needs to be completed within 2 hours of adding water.  Compaction is performed with a vibratory, footed roller weighing at least 10 tons (9 metric tons).  However, the final rolling is performed with a smooth drum roller without any vibration.

For the compaction testing criteria, use 98 percent of the maximum dry density and use the one-point Proctor method in Supplement 1015 to determine the maximum dry density.  In some cases, the test section method or the moisture-density curves developed by the Contractor may be used to determine the maximum dry density.

Check the depth of the stabilization by digging a hole.  Apply phenolphthalein or dilute hydrochloric acid to the side of the hole to check for the presence of lime or cement.  Phenolphthalein will turn purple and dilute hydrochloric acid will fizz.

Figure 206.C – Checking depth of Soil Stabilization with Phenolphthalein

Curing (206.05.D)

The chemically stabilized subgrade must cure for at least 5 days.  The surface of the chemically stabilized subgrade is covered with an emulsified asphalt (prime coat) or curing compound to retain moisture in the subgrade during the curing period.  Before the curing coat is applied, the surface must be wet.  If the surface has dried out (turns white) before the curing coat is applied, the Contractor needs to add more water to the surface.

The curing coat must uniformly cover the surface of the chemically stabilized subgrade.  The following photos show an example of good coverage and poor coverage using a curing compound.

Figure 206.D – Example of Good Coverage with Curing Compound

Figure 206.E – Example of Poor Coverage with Curing Compound

Curing coats can leach off the subgrade if not cured completely prior to a rain event.  During the curing period, all equipment should stay off the subgrade.

Proof Rolling (206.05.E)

Proof roll the chemically stabilized subgrade after the cure period.  If the stabilization was performed properly, and the planned depth of stabilization was adequate, there should be no deflection or rutting.

Mixture Design for Chemically Stabilized Soils (206.06)

If a pay item for Mixture Design for Chemically Stabilized Soils is included in the plans, then the Contractor uses the testing program described in Supplement 1120 to determine the spreading rate for the chemical.  Different mixtures of the soil and chemical are tested for unconfined compressive strength.  The results are used to determine the percentage of chemical used in the field.  The common increase in strength ranges from 20 psi to 100 psi with lime and from 50 psi to 200 psi with cement.

Method of Measurement (206.07)

The mixture design pay item also includes verification testing of the stabilized subgrade. For this reason, the Department pays for only two-thirds of the lump sum item for mixture design testing after the mixture design is complete.  The other one-third is paid after the chemically stabilized subgrade is completed.

Documentation Requirements - 206 Chemically Stabilized Subgrade

1.        Materials per 206.02.

2.        Check spreading rate for lime, cement, or lime kiln dust.

3.        Verify subgrade line and grade.

4.        Verify subgrade stability with proof roller, if variable locations. 

5.        Document the construction: spreading, mixing, and compaction.

6.        Perform the compaction testing according to Supplement 1015.

7.        Proof rolling results.

8.        Measure and pay according to 206.07 and 206.08.

9.        Document on CA-EW-2, CA-EW-12, CA-D-1, and CA-D-3. Do not duplicate the information on all forms unless necessary.

208 Rock Blasting

General Information

This section only covers the basic concepts of rock blasting.  The topic is covered in more detail in the FHWA manual, Rock Blasting and Overbreak Control, FHWA-HI-92-001. Many of the figures and specification concepts originated from this manual.  The manual is available on the FHWA website:

www.fhwa.dot.gov/engineering/geotech/library_listing.cfm

There used to be a training course from NHI for Rock Blasting and Overbreak Control, but unfortunately this course is no longer available from NHI.

Rock Blasting Basics

Rock blasting consists of drilling holes in the rock at depths, in diameters, and at spacing so that the ANFO, which is a mixture of Ammonium Nitrate (fertilizer) and Fuel Oil (diesel fuel), can fracture the rock in a controlled manner.  The rock must fracture enough to displace it and break it down to the size of the intended use.

The specifications limit the way blasting contractors can blast to ensure that rock or blast vibrations do not harm people or adjacent property.

Blasting Free Body Diagram

The basic geometry for rock blasting is shown in Figure 208.A.

Figure 208.A – Rock Blasting Free Body Diagram

Holes are drilled to the required depth in order to remove the rock and then filled with ANFO (the charge length).  The charge is topped off with stemming, which helps to hold the blast down.  The free body diagram on the right-hand side of Figure 208.A shows the explosive pressure (P) and moment (M) from the blast.

The blaster and blasting consultant can arrange the geometry of the blast for optimal breakage.  This is done so that P and M do not exceed the amount needed to break the rock.  Excessive P and M causes flyrock and excessive air blast and vibrations, which can cause damage and injury.

Blasting Geometry and Symbols

Figure 208.B further defines the rock blasting geometry.

Figure 208.B – Rock Blasting Geometry and Symbols

Figure 208.B illustrates the following blast geometry parameters:

§  B (Burden) is the distance between the free face and the first hole.

§  T is the stemming (the inert material in the hole).

§  L is the length of the bench height.

§  H is the blasthole depth.

§  PC is the powder column length (ANFO).

§  J is the subdrill depth or the depth the hole extends below the planned cut.

Two main parameters to remember here are the L/B ratio and the stemming height.

Hole Spacing and Timing

The top view of the rock blasting geometry is shown in Figure 208.C.  Notice the distance B is still the distance to the free face.  The distance S, or spacing of the holes, is a function of the burden.

Figure 208.C – Rock Blasting (Top View)

The spacing of the holes and the timing (or delay) of the holes are part of the blasting design.  The bottom illustration in Figure 208.C shows how the blast is delayed by the sequencing numbers.  Each hole may be blasted milliseconds apart to control the blast.  The row-to-row shots are certainly time delayed.

An initiation system transfers the detonation signal from hole-to-hole at precise times. Plastic shock tubes or electric caps using a timing system are generally employed.  A shock tube is non-electric, instantaneous, and has a thin reactive powder that propagates the shock wave signal.

The timing or delay minimizes the pounds of explosive per delay period. This can significantly control noise and vibration effects.  It would be a disaster if all the holes went off at the same time.

The design variables of burden, stemming, subdrill length, spacing, and timing are selected to maximize fragmentation and to minimize excessive vibration, air blast, and flyrock.

Effects of L/B Ratio

Figure 208.D shows what happens when the ratio between the distance L (bench height) and B (burden) is changed.  Potential blasting problems are decreased as the ratio is increased.  As this ratio is decreased, these problems are increased.

Stiffness Ratio (L/B)

1

2

3

4

Fragmentation

Poor

Fair

Good

Excellent

Air Blast

Severe

Fair

Good

Excellent

Flyrock

Severe

Fair

Good

Excellent

Ground Vibration

Severe

Fair

Good

Excellent

Comments

Severe backbreak and toe problems.  Do not shoot.  REDESIGN!

Redesign if possible.

Good control and fragmentation

No increased benefit by increasing stiffness ratio above 4.

Figure 208.D – Potential Problems as it Relates to Stiffness Ratio L/B

The specifications in 208.06.C require that this ratio be greater than one.  The blasting contractor designs the correct timing, hole spacing, and stemming. Historically, blasters in Ohio have not had problems with designs having an L/B ratio near one.  Local blasters are very familiar with local geology as well.

Generally, a ratio near one maximizes the rock blasting production.  The main problem with designing a ratio near one is that the rock generally fractures in large chunks.  This can pose problems for the Contractors when trying to use the material for fill.  When the ratio is increased, it can decrease the particle size of the rock.  This allows the material to easily be used as fill.

Proper Burden

In order to ensure that the blaster is using the proper burden, follow this rule of thumb: the burden is usually 24 to 30 times the production hole diameter. For example:

If the production holes have a diameter of 6 inches (0.5 feet), then the burden should be:

24 × 0.5 ft = 12 ft          or          30 × 0.5 ft = 15 ft

The burden for the shot should be between 12 and 15 feet.

Effects of Stemming

The specifications in 208.06.E require that the stemming depth (T) of inert material be at least 0.7 times the burden (B).  This helps control the air blast.

Figure 208.E depicts the effects of stemming.  If effective, the blast direction is lateral.  If the stemming is ineffective, the blast can blow upward and cause excessive air blast. Notice in the poor example, the blast cuts back into the cut slope.  This is an obvious problem.

Figure 208.E – Stemming Effects

Drill cuttings are normally used for stemming.  However, when blasting in water-filled production holes or when blasting within 200 feet of a structure, the stemming material is changed to prevent problems.  For holes less than 4 inches in diameter, crushed No. 8 stone is required.  For holes 4 inches in diameter or larger, No. 57 stone is required.  This helps to hold the blast down better.

Effects of Timing

Timing of the blast is another important parameter.  Figure 208.F depicts the effects of poor and good timing.

Figure 208.F – Timing Effects

With correct timing, the blast has a distinct lateral movement.  With poor timing, the movement is more upright and has potential problems.

Vibration and Air Blast Monitoring (208.15 and 208.16)

The blaster is required to design the burden, stemming, subdrill length, spacing, and timing to minimize excessive vibration, air blast, and flyrock.  The blaster must monitor the air blast and vibration for every shot at the nearest structure.  Seismographs are used to monitor the vibration.

Specialized equipment is used to monitor the air blast.  The maximum air blast, in 208.16.A, is required to be under 134 dB.  The air blast limit may need to be lower in order to prevent damage.

The specification does not give vibration limits for blasting. Since each site is different, and the blasting contractor is responsible for all damage caused by the blast, the blaster hires a vibration specialist to determine the safe vibration limits. A typical vibration criterion is given in Figure 208.G.   This is from the US Bureau of Mines.

To lower the air blast, check the stemming height and type of material used for the stemming.  Thin or thick areas of the burden may create excess air blast and flyrock.  Measure the burden to the free face to ensure a uniform burden.

To lower the vibration everything needs to be checked.  This includes the blast design and layout of the blast holes.

Figure 208.G – Typical Vibration Blasting Criteria

Each blast has a particle velocity and frequency.  The project can plot these values on the chart in Figure 208.G.  If the point is lower than the plotted line, the blast is within limits that are generally considered to be safe.

Presplitting (208.09)

Presplitting is a very effective method of controlling the final appearance of steep slopes; it can result in a clean sheared face.  Presplitting is required when the slope is steeper than 1H:1V and deeper than 5 feet.

Specialized presplit blasting explosives are used.  Hole diameters are approximately 3 inches, and the presplit holes are blasted prior to the production blast.  The presplit hole spacing starts at 36 inches.  This is adjusted to obtain a good, shear face of the rock.

Documentation Requirements - 208 Rock Blasting

1.        Accept pre-blast survey.

2.        Verify the experience of the blasting specialists.

3.        Accept and verify the blasting plan.

4.        Ensure that the CA-EW-10 Item 208 Blasting Drilling Log is prepared by the driller.

5.        Review the blasting area for blasting plan dimensions with the blasting consultant.

6.        Control blasting is used on cut slopes steeper than 1:1 and deeper than 5 feet (1.5 m).  Techniques are outlined in Section 208.10.

7.        Production blasting is used for widely spaced production holes in the main excavation.

8.        Review the regulations of explosives as outlined in Section 107.09.

9.        A blasting plan is required at least 2 weeks before drilling begins. 

10.     Review the detailed blasting plan of test shots.

11.     Document test sections and drilling patterns.

12.     Document safety procedures as outlined in 208.08.  Ensure that the CA-EW-11 Item 208 Rock Blasting Site Security Plan is prepared by the blaster.

13.     Witness all shots.  Inspect all shots using the CA-EW-9 Item 208 Rock Blasting Field Inspection Form.

14.     Check vibration, air blast, and flyrock for all blasts.

15.     Check monitoring wells with Hydrologist.

16.     Check the presplit face and requirements.

17.     Measure presplit areas.

18.     Monitor blasting consultants’ hours.

19.     Review contractor’s record keeping for explosives and blasting logs.

20.     Review monthly blasting report.

21.     Document on the CA-EW-9, CA-EW-10, CA-EW-11 and the CA-D-2.  Do not repeat information on other forms listed unless necessary.

209 Linear Grading

Linear grading consists of grading along the edge of pavement.  This item also includes a pay item for cleaning drainage ditches.  Because of the simplicity this item of work, no further detailed explanation of the item is required in this manual.

Documentation Requirements - 209 Linear Grading

1.        Verify plan dimensions.

2.        Verify materials.

3.        State method of excavation (grader, milling machine, etc.).

4.        Statement as to how excavated material is disposed.

5.        Construct the embankment and subgrade.

6.        Areas graded too much must be filled with material used for reconditioning shoulders (C&MS 617) at the Contractor’s expense.

7.        Measure and pay per 209.08.

8.        Check completed work.

9.        Measure borrow, if required.  Document on CA-EW-1.

10.     Measure pay according to 209.08 and 209.09.

11.     Document on CA-D-2 and CA-EW-12.  Do not duplicate the information on these forms unless necessary.

250 Pavement Repairs

251 Partial Depth Repair

Description (251.01)

This work consists of partial depth removal of existing pavement in areas exhibiting surface deterioration, applying tack coat, and placing and compacting asphalt concrete.

Removal of Existing Pavement (251.02)

Mark the areas in rectangular shapes.  Unless specified, the pavement should be removed to the full width of the traffic lane at transverse joints and along the longitudinal joint.  Ensure pavement is removed to the depth shown in the plans and that adjacent pavement is not damaged.  If the adjacent pavement is damaged, remove all loose pavement to the depth specified in the plans.

Removed pavement shall be disposed of in accordance with 202.02.  The Inspector shall determine and document where and how pavement is to be disposed by the Contractor.

Placement of Asphalt Concrete (251.03)

The exposed surfaces must be thoroughly coated with 407.02 material to fill all cracks and joint openings.  The approved 448 asphalt concrete must be placed and compacted in as many lifts as necessary to finish flush with the adjacent pavement surface. 

The final lift must be compacted using a Type I pneumatic tire roller that conforms to 401.13.  At least 18 passes should be made over all points on the entire surface of the repair area.  A pass is defined as one movement of the roller over the surface of the patch.  As the rolling progresses, additional patching material may need to be added in order to produce a smooth surface, flush with the existing pavement surface.

Each lift shall be continuously compacted while the material is in a workable condition throughout the depth of the lift.

Unless the repair area is scheduled to be covered with an asphalt overlay within 60 days, trim the limits of the repair area to form a vertical face 1-1/2 inches (38 mm) deep from the surface before placing the final asphalt concrete layer adjacent to the existing pavement.

If the Contract does not include resurfacing, seal the perimeter surface of the repaired areas with a 4-inch (100 mm) wide strip of approved 702.04 asphalt material, RS-1, RS-2, CRS-1, CRS-2, or 702.01 approved PG binder.

Documentation Requirements - 251 Partial Depth Pavement Repair

1.        Mark and record areas to be repaired in rectangular shapes.

2.        Document the removal of deteriorated pavement to a suitable depth as specified by plan or as directed by the Engineer.

3.        Document the disposal of removed pavement.

4.        Document that the area was cleaned and tacked with 407 tack coat.

5.        Document the placement and compaction (number of lifts and compaction method) of approved 448 Type I asphalt.

6.        Document the location of repairs, measurements, and calculations, and pay per 251.04.

7.        Show documentation on CA-D-6 or other approved form.

252 Full Depth Rigid Pavement Removal and Flexible Replacement

Description (252.01)

This work consists of the full-depth removal of existing rigid pavement in areas exhibiting deterioration, correcting the subgrade, placing and compacting asphalt concrete, and restoring the shoulders.

Removal of Existing Pavement (252.02)

Pavement Sawing

The Engineer marks the limits of the areas to be repaired.  The minimum longitudinal length of a repair is 6 feet (1.8 meters).  All pavement repairs are the full lane width, unless otherwise detailed by the plan.

The existing pavement is sawed full-depth, at the limits established by the Engineer, with a diamond saw blade.  All diamond saw cuts shall be perpendicular to the surface of the pavement.  Normally, the existing concrete pavement thickness is given in the plan.  There may be older projects where the existing pavement was built thicker than specified in the new repair plan.  Concrete sawing and removal depths may be as much as 1 inch (25 mm) greater than indicated on the repair plan without additional compensation to the Contractor.

If there is an existing asphalt overlay on the concrete pavement, the Contractor may elect to saw full-depth through the asphalt concrete and the Portland cement concrete.  Depending on the thickness of each material, the Contractor may not be capable of sawing through both courses and may elect to make an offset saw cut through the asphalt course. The Contractor would then remove enough asphalt to allow room for a diamond saw that would saw full-depth through the concrete pavement.  If the Contractor elects to make offset cuts to facilitate the removal, the offset cut will not be measured for payment; only full-depth saw cuts that are made at the limits of the removal are measured for payment.  Intermediate saw cuts made by the Contractor to facilitate removal by the lift-out method are not measured for payment.

During hot weather, it may be necessary for the Contractor to saw only at night or in the morning when cooler temperatures prevail.  Concrete pavement heats up and expands as temperatures rise during hot summer days.  Diamond saw blades could be pinched and locked up while sawing the expanding pavement slabs.  Some contractors use a carbide-tipped saw to cut through pavement within the repair area.  This is permitted provided that the Contractor does not damage the base under the pavement that is to be removed.  All perimeter saw cuts must be made with diamond saws.

Pavement Removal

Removal of the concrete follows the full-depth sawing operation.  The lift-out method is required in order to not disturb the base under the pavement and to minimize the damage to the adjacent pavement that is to remain.  Holes are drilled within the removal area and lift pins are inserted.  The slab, or portion of the slab, is then removed by lifting the slab vertically with a crane or large backhoe.  After lifting, loose debris left behind is removed by hand methods. 

Removed pavement shall be disposed of in accordance with 202.02.  The Inspector shall determine and document where and how pavement is to be disposed of by the Contractor.

The use of a pavement breaker and backhoe for removal is not permitted unless the Engineer determines that the lift-out method is not practical due to extensively deteriorated pavement, the existence of asphalt concrete full-depth repairs, or old concrete pavement repairs, which are extensively cracked and deteriorated.  There will be no additional compensation for the removal of existing pavement with a pavement breaker and backhoe.

Correction of Subgrade (252.03)

Prior to placing asphalt concrete in the removal area, any base or subgrade that is disturbed below the level of clean out is removed.  The repair area must be compacted to the satisfaction of the Engineer.  All vertical faces shall be cleaned and coated with asphalt material according to 401.14.

Placement of Asphalt Concrete (252.04)

The pavement replacement is constructed by placing and compacting Item 301 or 448 Type 2 material in two or more lifts according to 401.16.  Note: The plans for the project may specify the use of another material.  The first lift, and all intermediate lifts, must be thoroughly and uniformly compacted using suitable, mechanical, compaction equipment operated over the entire replacement area.

The final lift must be compacted using a pneumatic tire roller that conforms to 401.13.  At least 18 passes should be made over all points on the entire surface of the repair area.  A pass is defined as one movement of the roller over the surface of the patch.  As the rolling progresses, additional patching material may need to be added in order to produce a smooth surface, flush with the existing pavement surface.

Each lift shall be continuously compacted while the material is in a workable condition throughout the depth of the lift.

If an overlay is not scheduled to be placed within 60 days of the repair, the perimeter of the repair shall be trimmed vertically 1-1/2 inches deep from the surface before placing the final lift of asphalt concrete.

 If the Contract does not include resurfacing, the perimeter surface of the repaired areas must be sealed with a 4-inch (100 mm) wide band by applying approved 702.04 asphalt material, RS-1, RS-2, CRS-1, CRS-2, or 702.01 approved PG binder.

After completing repairs, the existing shoulders must be repaired to the condition that existed prior to the repair work.

Documentation Requirements - 252 Full-Depth Rigid Removal and Flexible Replacement

1.        Locate, mark, and record all areas to be repaired.

2.        Measure and record saw cuts.  Full-depth saw cuts are an additional pay item paid by the linear foot.

3.        Document removal of deteriorated pavement.  Note condition of existing adjacent pavement.

4.        Document the disposal of removed pavement.

5.        Document preparation of subgrade.

6.        Document that the area was cleaned and tacked with 407 tack coat.

7.        Document the placement and compaction (number of lifts and compaction method) of approved 301 or 448 Type 2 asphalt or other as specified by plan.

8.        Document the location of repairs and saw cuts, measurements, and calculations, and pay per 252.06.

9.        Show documentation on CA-D-6 or other approved form.

253 Pavement Repair

Description (253.01)

This work consists of removing existing asphalt concrete, brick, Portland cement concrete, or aggregate pavement courses; shaping and compacting the exposed material; and placing new asphalt concrete pavement or aggregate and asphalt concrete pavement courses.

The plans show details about the repairs and replacement material.

Removal of Existing Pavement (253.02)

The Engineer shall mark all areas for removal.  The pavement shall be cut at the limits marked and removed.  Ensure that the pavement is removed to full-depth or to the depth shown in the plans, and ensure adjacent pavement is not damaged during removal.  If the adjacent pavement is damaged, remove all loose pavement to full-depth or to the depth specified in the plans.

Removed pavement shall be disposed of in accordance with 202.02.  The Inspector shall determine and document where and how pavement is being disposed by the Contractor.

Placement of Asphalt Concrete (253.03)

The exposed underlying material must be shaped and compacted.  The asphalt material shall be as specified in the plans.  Before placing asphalt concrete, all vertical faces of the existing pavement must be cleaned and coated with asphalt material according to 401.14.  The replacement material must be placed in appropriate lifts.  Each lift must be thoroughly and uniformly compacted using suitable compaction equipment.  The final lift must be flush with the existing pavement surface.

Compact the final lift using a pneumatic tire roller that conforms to 401.13.  The final lift should be compacted with at least 18 passes over all points on the entire surface of the repair area.  A pass is defined as one movement of the roller over the surface of the patch.  As the rolling progresses, add additional patching material in order to produce a smooth surface, flush with the existing pavement surface.

Continuously compact each lift while the material is in a workable condition throughout the depth of the lift.

If an overlay is not scheduled to be placed within 60 days of the repair, the perimeter of the repair shall be trimmed vertically 1-1/2 inches deep from the surface before placing the final lift of asphalt concrete.

If the Contract does not include resurfacing, the perimeter surface of the repaired areas must be sealed with a 4-inch (100 mm) wide band by applying approved 702.04 asphalt material, RS-1, RS-2, CRS-1, CRS-2, or 702.01 approved PG binder.

After completing repairs, the existing shoulders must be repaired to the condition that existed prior to the repair work.

Documentation Requirements - 253 Pavement Repair

1.        Locate, mark, and record all areas to be repaired.

2.        Document removal of deteriorated pavement.  Note condition of existing adjacent pavement.

3.        Document the disposal of removed pavement.

4.        Document preparation of subgrade.

5.        Document that the area was cleaned and tacked with 407 tack coat.

6.        Document the placement and compaction (number of lifts and compaction method) of approved 301 or 448 Type 2 asphalt or other as specified by plan.

7.        Document the location of repairs, measurements, and calculations, and pay per 253.05.

8.        Show documentation on CA-D-6 or other approved form.

254 Pavement Planing

Description (254.01)

This work consists of planing the existing pavement and disposing of the cuttings, and if specified in the Contract, patching the planed surface.  The pay description indicates the predominant type of pavement. 

Equipment (254.02)

The equipment used must be self-propelled and have sufficient power and stability to consistently and efficiently meet the requirements of 254.05 and the plans.  Equipment can have grinding, sawing, or milling type cutters.  The cutters must be mounted rigidly to the carrier and must be adjustable to control the depth of cut and cross-slope.  Longitudinal planing action shall be accomplished by using equipment with a suitable carrier wheelbase or with an automatic control system having an external reference.  Ensure that cross-slope adjustments or automatic controls are capable of producing a variable and a constant cross-slope, as required.

For small or confined areas, the Contractor may use suitable supplemental equipment or methods approved by the Engineer.

Planing (254.03)

The Engineer should mark the locations of signal loop detectors and notify the maintaining agency before the start of a planing operation.

The Contractor may make one or more planing passes, as necessary, over the designated area to obtain the depth specified in the plans.  Where establishing new pavement surface elevation or cross-slope, remove irregularities such as bumps, corrugations, and wheel ruts. Ensure that all cuttings are removed from the surface following each pass. 

Before opening the completed area to traffic, the surface shall be thoroughly cleaned of all loose material that would create a hazard or nuisance or would redeposit into the surface texture. 

Cuttings shall be disposed of in accordance with 202.02.  The Inspector shall determine and document where and how cuttings are to be disposed of by the Contractor.

Monitor and control dust, pavement contamination, and the scattering of loose particles to acceptable levels during planing and cleaning operations.

If damage occurs to the adjacent pavement by planing operations, repair the damaged area by matching the adjacent pavement with the planed area in terms of smoothness and mix type.

Surface Patching (254.04)

After planning, mark areas of spalled or dislodged unsound pavement.  Before patching, the areas shall be cleaned of loose materials and coated with 407.02 asphalt material.  The area shall be patched with Item 448, Type 1 asphalt.  Patched areas shall be compacted to be flush and level with adjacent pavement.

Surface Tolerances (254.05)

The surface shall be planed free from grooves, ridges, gouges, or other irregularities detrimental to the safe operation of vehicles on the planed surface.

If the Contract specifies planing without resurfacing, the surface shall be planed to a smoothness of 1/8 inch in 10 feet (3 mm in 3 m).  If the Contract specifies resurfacing after planing, the surface shall be planed to a smoothness of 1/4 inch in 10 feet (6 mm in 3 m).  The surfaces shall be matched at the edges of adjacent passes within 1/8 inch (3 mm).  Ensure that the cross-slope of the planed surface is within 3/8 inch in 10 feet (10 mm in 3 m) of the specified cross-slope.

Method of Measurement and Basis of Payment (254.06, 254.07)

Measure the quantity of planing and patching, and convert to square yards for payment.

Payment will not be made for repairs due to damage caused by the planing operation.

If the depth of the planed surface is increased by more than 3/8 inch (9.5 mm), the Department will recalculate the surface area for payment by multiplying the surface area measurement by a factor that equals the new depth, divided by the plan depth.  Additional depth will only be paid for with prior approval. 

Documentation Requirements - 254 Pavement Planing

1.        Document the location and/or stations of work.

2.        Note locations of all loop detectors for traffic signals and notify the proper authority before removing.

3.        Document the type of equipment used.

4.        Record the depth of cut and cross-slope grade.

5.        Document the final disposition of cuttings.

6.        Document method of removal (air hammer, bobcat, hand tools, etc.) around manholes, water-stops, catch basins, curb drains, etc.

7.        Measure and pay as per 254.06.

8.        Document on CA-D-1A or 1B or other approved form.

255 Full Depth Pavement Removal and Rigid Replacement

General

During the life of concrete pavement, it is sometimes necessary to make repairs to stop progressive deterioration and to maintain serviceability. Timely repairs restore quality and provide the rideability and life expectancy for which the pavement was designed.

Problems may occur at various stages of the pavement life; it is important that these problems are corrected as they arise.  Corrections are often necessary during construction, and these repairs must be of the highest standard in order to achieve the anticipated pavement life.  This section establishes a standard repair procedure and provides uniform application for repairs.  These standards are applicable at any time throughout the pavement life.

Concrete pavement repairs are classified as full-depth pavement replacement and thin-bonded patching.  Full-depth replacement applies when the damage is more extensive than surface scaling or spalling and requires removal and replacement for the full depth of the slab.  Thin-bonded patching applies to surface scaling and spalling, spalling at edges and joints, and other surface deterioration that does not extend below the pavement mesh.  Compliance with all the provisions of the following standards is necessary to assure durable repairs and to permanently restore the quality of the pavement.

Description (255.01)

When Standard Construction Drawing BP-2.5 is called for, rigid replacement applies to the work.  The basic process of full-depth repairs includes the following:

1.        Full-depth diamond blade sawing.

2.        Removing the existing pavement full-depth.

3.        Removing base material, if specified.

4.        Compaction of base material.

5.        Drilling dowel bar or tie bar holes.

6.        Furnishing and grouting dowel bars and tiebars.

7.        Installing mesh when required.

8.        Placing, consolidating, finishing, and curing concrete.

9.        Sealing of repaired surface perimeter.

10.     Restoring affected shoulders.

Materials (255.02)

Concrete

The concrete to be used must be 499 Class QC 1, QC FS, or QC MS and will be called out in the pay item description. Additionally, Rapid Repair Concrete Mix (RRCM) may be called out in the pay item description. The RRCM mix will require the Contractor to develop and submit a mix design to the Engineer. The RRCM mix design must develop 400 psi flexural strength in no less than 4 hours and no more than 6 hours using a 6-inch x 6-inch (150 mm x 150 mm) beam sample conforming to ASTM C293. The Engineer has 10 days to review and accept or reject the RRCM design.

Curing Materials

The curing material to be furnished and used must be white-pigmented, liquid membrane forming compounds meeting 705.07.  The shipping containers must be equipped with mechanical agitators to agitate the material prior to use. 

Non-shrink, Non-metallic Grout 

The dowels and tiebars must be anchored with non-shrink, non-metallic grout material and must set within 30 minutes.  Item 705.20 provides the requirements for grout.  The Inspector should check to ensure the proposed grout is on ODOT’s Qualified Products List.

Reinforcing Steel 709.00

Reinforcing steel for dowel bars, basket assemblies, deformed bars, tiebars, hook bolts, wiggle bolts, and couplings must be epoxy coated steel.

Welded Steel Wire Fabric

Welded steel wire fabric, also called steel mesh, must comply with Item 709.00.

Dowel Bars and Basket Assemblies

Dowel bars may be epoxy coated steel 709.13 or Fiber Reinforced Polymer (FRP) bars 705.01.  Basket assemblies must be epoxy coated steel.

Removal of Existing Pavement (255.03)

The Engineer must mark the limits of the areas to be repaired.  The minimum longitudinal length of a repair is 6 feet (1.8 meters).  All pavement repairs must be the full lane width, unless otherwise detailed by the plans.

The existing pavement is sawed full-depth at the limits established by the Engineer with a diamond saw blade.  Normally, the existing concrete pavement thickness is given in the plans; however, there may be projects where the existing pavement was built thicker than shown in the repair plan. 

Figure 255.A – Full-Depth Diamond Blade Saws

Concrete sawing and removal depths may be as much as 1 inch (25 mm) greater than indicated on the repair plan without additional compensation to the Contractor.

If there is an existing asphalt overlay on the concrete pavement, the Contractor may elect to saw full-depth through the asphalt concrete and the Portland cement concrete.  Depending on the thickness of each material, the Contractor may not be capable of sawing through both courses and may make an offset saw cut through the asphalt course, remove enough asphalt to allow room for a diamond saw, then make a full-depth saw cut through the concrete pavement.  If the Contractor elects to make offset cuts to facilitate removal, the offset cut will not be measured for payment. Only full-depth saw cuts that are made at the limits of the removal are measured for payment.  Any intermediate saw cuts made by the Contractor to facilitate removal by the lift out method are not measured for payment.

During hot weather, it may be necessary for the Contractor to saw only at night or in the morning when cooler temperatures prevail.  Concrete pavement heats up and expands as temperatures rise during hot summer days.  Diamond saw blades could be pinched and lock up when sawing due to slab expansion.  Some contractors use a carbide-tipped saw to cut through the pavement within the repair area.  This is permitted provided that the Contractor does not damage the base under the pavement to be removed.  All perimeter saw cuts must be made with diamond saws.

Figure 255.B – Pavement Removal by the Lift-out Method

Removal of the concrete follows the full-depth sawing operation.  The lift-out method is required in order to not disturb the base material under the pavement and to minimize damage to the adjacent pavement that is to remain.  Holes are drilled within the removal area and lift pins are inserted.  The slab, or portion of the slab, is then removed by lifting the slab vertically with a crane or large backhoe.  After lifting, loose debris left behind is removed by hand.  The removed pavement is disposed of in accordance with Item 202.02. 

The use of a pavement breaker and backhoe for removal is not permitted unless the Engineer determines that the lift-out method is not practical due to extensively deteriorated pavement, the existence of asphalt concrete full-depth repairs, or old concrete pavement repairs, which are extensively cracked and deteriorated.  There will be no additional compensation for removal of the existing pavement with a pavement breaker and backhoe.

Regardless of the method used to remove the pavement, if the face of the pavement to remain is damaged by sawing or removal operations, an additional full-depth saw cut is required for the full width of the lane or lanes at a distance from the first cut, which includes the damaged pavement.  The additional pavement repair area and the additional saw cut is not measured for payment.

After pavement is removed from the area to be repaired, an additional saw cut must be made if the face of the remaining pavement or shoulder is deteriorated on the bottom to a height greater than 1/4 of the pavement thickness.  The additional saw cut should encompass the deteriorated areas.  The additional saw cut and repair area is measured for payment.

Removed pavement shall be disposed of in accordance with 202.02.  The Inspector shall determine and document where and how pavement is being disposed by the Contractor.

Correction of Subgrade (255.04)

Prior to placing the concrete in the removal area, and before installing dowels or tiebars, shape and compact the base or subgrade material.  Any area that has been over-excavated must be filled with concrete. 

Figure 255.C – Debris Remaining after Removal by the Lift-Out Method is Removed by Hand Methods

Figure 255.D – Compaction of Base

If undercut joints at the limits of the repair areas are specified, the Contractor must be careful when removing the base material to create the undercut section.  The undercut section is the void created by removing the base material from underneath the existing, remaining pavement.  This undercut will be filled with concrete when placing the new pavement repair.  Refer to Standard Construction Drawing BP-2.5 for undercut joint details.  Damage to the bottom of the slab that is to remain cannot be tolerated.  Any damage caused by the Contractor’s operations requires additional removal and replacement at no additional cost.  If a backhoe bucket plate is used, exercise care, or use hand methods to excavate under the existing slab.  Undercut work is incidental and included in the pay item.

Placing Dowels and Tiebars (255.05)

Dowels could be smooth or deformed steel bars depending on the type of joint (transverse contraction or transverse tied).  Smooth dowels are 1-1/2 inch (38 mm) in diameter by 14 inches (355 mm) in length.  Fiber-reinforced polymer dowel bars may be used in lieu of smooth steel dowels.  Deformed bars are No. 11 (No. 35M) by 14 inches (355 mm) in length.  Refer to Standard Construction Drawing BP-2.5 for details on tied and contraction joint requirements. 

Holes for dowels and tie bars are drilled in the existing concrete slab by using hydraulic or electric drills.  Drilling is to be done in a manner that will not spall or damage the existing concrete.  Pneumatic drills are not to be used.  Holes must be drilled with a device that allows independent adjustment of all drill shafts in the horizontal and vertical direction.  The device must be capable of drilling a minimum of three holes at one time. 

Holes for dowel and tie bars are to be centered at mid-slab within a tolerance of ±1/2 inch (13 mm).  Dowels are spaced starting 12 inches (300 mm) from the outside edge of pavement, are spaced at 12 inches (305 mm), and stop 24 inches (600 mm) from the adjacent lane to avoid hitting existing tiebars at the longitudinal joint.  This will result in 10 bars in each 12 foot lane.  The Contractor must drill dowel holes parallel to the pavement surface and the centerline, otherwise the smooth dowels will not perform properly when the pavement expands and contracts.

Figure 255.E – Hole Drilling Equipment

Holes for dowels or tiebars must be 1-5/8 inches (41 mm) in diameter and a minimum of 7 inches (178 mm) deep into the concrete.

Longitudinal Joints

Full-depth repairs that are greater than 10 feet (3.0 meters) in length will require a tied longitudinal joint using No. 5 x 24-inch (No. 16M x 600) tiebars or hook bolts spaced at no more than 30 inches (760 mm) and not less than 24 inches (610 mm).  Refer to Standard Construction Drawings BP-2.1 and BP-2.5 for more details.  Holes for longitudinal tiebars must be 3/4 inches (19 mm) in diameter and a minimum of 12 inches (300 mm) deep into the concrete.

Grouting Dowels or Tiebars

This section details the requirements for transverse dowels and tiebars.  The requirements for tied longitudinal joints are the same; however, the bar dimensions differ.  All dowels and tiebars must be grouted into place with a non-shrink, non-metallic grout material.  Prior to injecting grout, the holes must be blown clean with oil-free compressed air.  The hole must be dry and frost free before grouting dowels or tiebars. 

The grout must be injected pneumatically into the back of the hole and the dowel or tiebar inserted 7 inches (178 mm) into the hole.  A nylon or plastic washer (called a grout retention disc) is then pushed flush against the saw cut after the bar is installed to keep the grout in the hole.  Grout retention discs must be clear or opaque white in color.  Sufficient grout must be used to completely fill all voids around the bar, including any spalling at the face of the saw cut.  Grout should extrude through the slot in the grout retention disc after filling and inserting the dowel or tiebar.  Other methods of installing dowels or tiebars are not permitted. 

Figure 255.F – Typical Grout Injection Equipment

Figure 255.G – Pneumatic Injection of  Grout into Hole Prior to Installing Dowel Bar with Grout Retention Disc

Most contractors pump the resin and hardener from separate pressure pots. The two materials are mixed immediately before being injected into the hole through a baffled mixing tube.  In cooler temperatures, it may be necessary to heat the grout materials to promote flow and to allow set up in the required 30 minute time period.  Dowels or tiebars must be held in proper alignment until the grout has hardened.

Figure 255.H – Insert Steel Rods with Grout Discs in Place

Figure 255.I – Using a Spud Bar to Push Steel Rod into Place

Placement of Portland Cement Concrete (255.06)

Placement of the concrete can begin when the grout around dowels or tiebars has hardened.  Smooth dowels must be coated with new, light form oil before concrete is placed.  Rigid forms are required at the outside edge of the full-depth repair.  The concrete must be placed in a continuous operation and consolidated with internal vibration.

Figure 255.J – Rigid Forms Installed at Shoulders

Full-depth repairs that are greater than 10 feet (3.0 meters) in length, or will be opened to traffic within 24 hours of placement, require W8.5 or D8.5 wire fabric reinforcement.  The clearance from the end of the wire fabric to the edge of the pavement or new transverse joint is 4 ± 2 inches (100 mm ± 50 mm).  Refer to Standard Construction Drawing BP-2.5 for details.

When using RRCM concrete the Contractor is required to install maturity sensors to measure the maturity of each day’s placement. At least two sensors should be installed for each work day. Install the first sensor where maturity gain is expected to be the slowest. Maturity gain is typically slowest in the thinnest section of pavement or volumetrically smallest patch or repair. If all sections, patches, or repairs have the same dimensions and no concrete is expected to gain maturity slower than another, install the first sensor randomly in concrete from any load, except the last load. Install the other sensor in concrete from the last load mixed and placed that day. See Supplement 1098 for additional details on maturity curve development and use during construction.

Figure 255.K – Screeding of Repair Area

Figure 255.L – Bull Floating the Repair Area

Specifications require that repairs less than 12 feet (3.7 meters) in length be screeded parallel with the centerline.  If the repair is 12 feet (3.7 meters) or longer in length, the screed must be perpendicular to the centerline.  After screeding and floating is complete, the surface must be tested with a 10 foot (3.0 meter) straightedge before the concrete hardens to ensure that the transition on and off the repair meets a tolerance of 1/8 inch in 10 feet (3 mm in 3.0 m).  Any high or low areas must be corrected and the surface rechecked to assure compliance.

The surface finish of the concrete repair must match the adjacent concrete.  If the adjacent pavement is smoothed with a burlap drag, the patch should have the same finish.  If the patch texture is different, it may be very noticeable when traveling over the patch at normal traffic speed.

After finishing and straightedge checking is complete, the concrete must be cured with white pigmented curing membrane as per 705.07, Type 2.  A uniform coverage of membrane is required at an application rate of 150 square feet per gallon (1 liter per 3.7 square meters).

Wearing Course Replacement (255.07)

If asphalt was removed from the top of the existing pavement, it must be replaced with either 301 or 448 Type II material as shown in the plans.  Compact these mixtures as approved by the Engineer using any of the roller types specified in 401.13.  Prior to placing the hot mix asphalt concrete, apply a tack coat on the repaired surface per 407.

Vertically trim all transverse joints to a 1-1/2 inch (38 mm) minimum before placing the final asphalt concrete layer adjacent to the existing pavement.

Seal the perimeter surface of repaired areas 4 inches (100 mm) wide by applying approved 702.04 asphalt material, RS-1, RS-2, CRS-1, CRS-2, or 702.01 approved PG binder.

Shoulders must be restored to the original line and grade with aggregate or asphalt concrete as directed by the Engineer or as shown in the plans.  Fill low areas and compact them flush with the surrounding shoulder.

Opening to Traffic (255.08)

Full-depth repairs can be opened to traffic when the concrete attains a modulus of rupture of 400 psi (2.8 Mpa).  For RCCM mixes, do not open the rigid replacement to traffic until the RCCM attains a modulus of rupture of 400 pounds per square inch (2.8 MPa) based on maturity testing. The time to obtain this strength will vary depending on the class of concrete used and the atmospheric conditions.

When traffic is maintained adjacent to the lane being repaired, the Contractor must schedule his work so that slab replacements are completed within 48 hours after removing the existing pavement.  At the end of a daily work shift, unfilled repairs, 10 feet (3.0 meters) and less in length must be covered with steel plates. 

The Contractor must plan work so that no repairs are left unfilled when work is suspended for holidays or weekends.  If the Contractor has removed pavement and is unable to complete the repairs in the above time, he must fill the areas with a suitable, temporary patch material to the satisfaction of the Engineer.  These areas must be maintained by the Contractor.

Method of Measurement (255.09)

The Department will measure the quantity of full-depth pavement removal and rigid replacement by the number of square yards (square meters) repaired in the completed and accepted work.

Full-depth pavement sawing is measured by the number of feet (meters) of perimeter full-depth saw cuts made in the completed and accepted work.  The Department will not measure any offset cuts, pressure relief cuts, or other saw cuts made to facilitate pavement removal.

Basis of Payment (255.10)

Payment is full compensation for all work specified in this item.  Payment for accepted quantities of the full-depth pavement removal and rigid replacement item is at the contract price per square yard (square meter).

Payment for the full-depth pavement sawing item is at the Contract price per linear foot (meter). The Department will not pay for additional concrete sawing and removal depths within 1 inch (25 mm) greater than those shown on the plans.

The Department will not pay for additional work to repair damage caused by pavement sawing or pavement removal.

The Department will include tack coat in the cost of the asphalt concrete. The Department will pay for asphalt concrete according to Item 301 or Item 448.

Documentation Requirements - 255 Full Depth Pavement Removal and Rigid Replacement

1.        Locate, mark, and record areas to be replaced.

2.        Document removal of existing pavement and note if damage occurred due to removal operation.

3.        Document the disposal of waste material.

4.        Measure and record saw cuts.  Full-depth saw cuts are an additional pay item paid by the linear foot.

5.        Document any damage to existing base material or subgrade during pavement removal operation.

6.        Document preparation and compaction of base material or subgrade.

7.        Document type of equipment used for drilling holes for dowel bars; depth of holes; holes blown clean before dowel bars placed.

8.        Document dowel and tiebar sizes, spacing, and alignment; approved grout, method of grout placement, and use of grout retention discs.

9.        Document placement of concrete in accordance with 451.06 and direction of screeding.

10.     Document surface tolerance checks with straightedge and any corrections made.

11.     Calculate and document curing compound used and required.

12.     Document times and results of beam breaks or maturity readings.

13.     Measure and pay as per 255.10. 

14.     Show documentation on CA-D-6 or other approved form.

256 Bonded Patching of Portland Cement Concrete Pavement

General

The success of a thin-bonded patch depends on complete removal of all unsound or damaged material, adequate bond between old and new concrete, use of “low slump” air-entrained concrete, and proper curing.  Successful patching depends on strict adherence to all requirements.

Description (256.01)

This work involves bonded patching of Portland cement concrete pavements in areas designated by the Engineer and includes:

1.        Marking repair areas using aerosol spray paint; minimum payment is 2 square feet (0.2 m²) for each area.

2.        Saw cutting the perimeter of all areas marked for repair.

3.        Removing loose and unsound concrete and asphalt patching materials from within the repair area.

4.        Removing sound concrete to obtain a minimum depth of 1-1/2 inch (38 mm).

5.        Preparing the surface by cleaning bonding surfaces using abrasive blasting.

6.        Applying a bonding grout for Type A, B, or C patches.

7.        Mixing, placing, finishing, and curing Type A, B, or C patch material.

8.        Checking surface for trueness using 10 foot (3 m) straightedge.

Materials (256.02)

Portland Cement

Type A patches require high early strength cement, 701.05.  Type B patches require quick setting concrete mortar, 705.21 Type I or II.  Type C patches require quick setting concrete mortar, Type II.

Fine Aggregate

Fine aggregate must meet the requirements for concrete aggregate specified in 703.02.

Coarse Aggregate, No. 8 Size

Coarse aggregate must meet the requirements for concrete aggregate specified in 703.02 and be No. 8 size.

Curing Compound

Curing compound must meet the requirements of 705.07.

Air-entraining Admixture

Air entraining admixtures must conform to 705.10.

Quick Setting Concrete Mortar

Prepackaged mortar material must conform to the requirements of 705.21.

Equipment (256.03)

Equipment must be milling machines, concrete saws, jackhammers, or other approved equipment that is capable of removing the existing surface material. Chipping hammers may not be heavier than 35 pound (16 kg) class.

Oil and moisture free compressed air is required to clean and abrasive blast prepared areas. 

An on-site concrete mixer with a minimum capacity of 2 cubic feet (0.06 cubic meters) is required to mix the patching material.

Removal of Unsound Concrete (256.04)

Figure 256.A – Areas to be Repaired are Marked by the Engineer

Figure 256.B – Perimeter of the Repair is Saw Cut a Minimum of 1 Inch Deep

The limits of the damaged area must first be determined and the repair area be established beyond the deteriorated area and into sound concrete.  A steel rod or steel chain may be used to “sound” the surface to determine hollow and deteriorated concrete.  The Engineer marks the limits of all bonded patches with spray paint provided by the Contractor.

Figure 256.C – Pavement Removal with Jackhammer

Figure 256.D – Pavement Removal by Milling Machine

The repair area should be square or rectangular.  The perimeter should be outlined by sawing to a vertical depth of approximately 1 inch (25 mm) to avoid feathered edges that usually spall.  Additional saw cuts within the outlined area aid the breakup and removal operation.  The Contractor must remove all unsound concrete materials and all loose or disintegrated concrete within the marked area.  Sound concrete must be removed to the minimum required depth within the patch area.  Concrete may be removed by jack hammering or milling.  The minimum depth of a repair is 1-1/2 inches (38 mm) except for the perimeter saw cuts which require a 1 inch (25 mm) minimum.  During removal operations, remove any reinforcing steel within the patch area by cutting or with a torch.

Figure 256.E – Abrasive Blasting of Repair Areas

Preparation of Patch Area (256.05)

After removal of pavement within the repair area, the area must be cleaned of all loose material, dirt, dust, asphalt, etc. by abrasive blasting and blowing out with oil- and moisture-free compressed air.  If water is used for cleaning, it must be mopped out thoroughly before abrasive blasting.  Abrasive blasting of the bonding surfaces must be done after the area has dried. The Contractor must comply with all state, regional, and local government agency requirements regarding control of dust generated by the abrasive blasting operation. 

Type B and C patching materials that do not use water as an activator may require additional surface preparation.  Check the manufacturer’s instructions to ensure surface preparation is done correctly.

If a bonded patch area is adjacent to a transverse or longitudinal joint, the joint must be reestablished by using a joint board or form that extends below the level of the patch and is as wide as the joint.  This board is to be removed about an hour after placing the patching material.

Figure 256.F – Adjacent Joints are Formed Prior to Placing the Patching Material

Bonding Grout Installation (256.06)

For Type A patches, prepare a grout of equal parts by volume of Portland cement, sand, and water to a consistency of a thick paint or slurry.  The grout should be brushed and scrubbed into the dry and clean bonding surfaces of the exposed concrete.  Grout should be placed immediately prior to placing the patching material.  Excess grout should not be allowed to collect in low spots.  Ideally, the grout should have a uniform thickness of 1/16 to 1/8 inch.

For Type B and C patches, the bonding grout should be mixed and applied per the manufacturer’s requirements. 

Figure 256.G – Portable Mortar Mixer used to Mix Bonding Grout and Patching Material

Figure 256.H – Bonding Grout is Brushed into the Dry Patch Area

Placing Patching Material (256.07)

The plans will specify the type of patching material to be used.  In all cases, after placing the patching material, screed patches 12 feet and less in length, parallel with the centerline and patches longer than 12 feet, perpendicular to the centerline.

While the patch material is still plastic, the surface of the patch should be checked with a 10 foot straightedge to ensure the final surface is flush with the edges of the adjacent pavement.  The straightedge is to be placed parallel to the centerline and drawn across the patch while checking for any high or low areas.  High or low spots that exceed 1/8 inch in 10 feet are to be immediately corrected.  After making any corrections, recheck the surface to ensure that there are no variations more than 1/8 inch high or low in 10 feet.

The surface of the completed patch is to be textured in the same manner as the adjacent pavement.

Type A Patch

Type A patching material is to be mixed in the field using 701.05 high-early-strength cement (Type III).  Ready mixed concrete is not permitted.  Use only enough water to make it cohesive and cause sufficient air entrainment.  One part of cement is combined with 1-1/2 parts of sand and 1-1/2 parts of No. 8 sized coarse aggregate and enough water to obtain a slump practical to place in the patch area.  Only the minimum amount of water is to be used and the slump must not exceed 4 inches.  A low slump mix will reduce shrinkage of the patch and ensure a good bond to the surrounding concrete.  An air entraining admixture is used to obtain 8 ± 2 percent air content. 

 Place the patching material while the grout is still wet, and vibrate the concrete in place after the patch area is slightly overfilled.  Strike off the concrete to the elevation of the adjacent concrete.

Type B Patch

This type of patching material is a quick-setting mortar that comes prepackaged.  The patching material must be pre-approved and must comply with 705.21 as Type I or II material.

Mix and place the material according to the manufacturer’s directions.  Add coarse aggregate, as needed, according to the manufacturer’s instructions.  Place the mortar mixture in the patch area.  If the manufacturer’s requirements specify using bonding grout, place the mixture while the bonding grout is still wet.  Slightly overfill, vibrate, and strike off the concrete.

Figure 256.I – Patching Material Placed and Consolidating with an Internal Vibrator

Figure 256.J – Patching Material Screeded Off Flush with Surrounding Pavement

Type C Patch

This type of patching material is also a quick-setting mortar that comes prepackaged.   The patching material must be pre-approved and must comply with 705.21 as Type II material.  Mix and place the material according to the manufacturer’s directions.  Add coarse aggregate, as needed, according to the manufacturer’s instructions.  Place the mortar mixture in the patch area.  If the manufacturer’s requirements specify using bonding grout, place the mixture while the bonding grout is still wet.  Slightly overfill, vibrate, and strike off the concrete.

Figure 256.K – Application of Curing Compound to New Bonded Concrete Patch

Figure 256.L – Completed Bonded Patches

Curing and Loading (256.08)

Type A patches must be cured with a white-pigmented, liquid membrane-forming compound conforming to 705.07 and applied at a rate of 150 square feet per gallon (1 Liter per 3.7 square meters).  The amount of curing required and used is to be documented.  A modulus of rupture of 400 psi (2.8 Mpa) must be obtained prior to opening to traffic.  Record the times and results of all beam breaks.

Cure Type B and Type C materials according to manufacturer’s directions.

Method of Measurement (256.09)

Project personnel must measure the repair areas and calculate the area in square feet (square meters) of completed and accepted work.  If a measured area is less than 2 square feet (0.2 square meters), the Engineer will increase pay to 2 square feet (0.2 square meters).

Basis of Payment (256.10)

Pay the contract price for accepted quantities per square feet (square meters) of Item 256, Bonded Patching of Portland Cement Concrete Pavements, Type A, B, or C.

Documentation Requirements - 256 Bonded Patching of Portland Cement Concrete Pavement

1.        Locate, mark, and record areas to be replaced.

2.        Document the method used to remove the existing surface material and unsound concrete, size of jackhammers, depth of repair area, removal of reinforcing steel, and method of cleaning.

3.        Document type of grout, mixing, and application.

4.        Document type of patch material, mixing, placement, screeding, surface check, texturing, and curing.

5.        Document the times and results of beam breaks.

6.        Measure and calculate the area of the repair for payment.

7.        Document on CA-D-6 or other approved form.

257 Diamond Grinding Portland Cement Concrete Pavement

Description (257.01)

This work consists of diamond grinding a rigid concrete pavement, normally the full width of the lane, in order to eliminate transverse cracking and transverse joint faulting.  The work results in a longitudinal, corduroy-type texture.  If done properly, the ride of the finished pavement surface will be improved and the skid resistance enhanced.

Final acceptance of a diamond ground pavement is done by surface measuring equipment, which is passed over the completed pavement and measures the surface profile.  This equipment is called a non-contact profilometer or a profiler.

Equipment (257.02)

Figure 257.A – Types of Diamond Grinding Equipment

Figure 257.B – Types of Diamond Grinding Equipment

Equipment requirements for diamond grinding:

§  Must be a power driven, self-propelled machine, specifically designed to smooth and texture Portland cement concrete pavement with diamond blades or diamond impregnated cylinder rings.

§  Diamond blades or diamond impregnated cylinder rings must be mounted on an arbor head that is a minimum of 3 feet long.

§  Must be capable of grinding the surface in the longitudinal direction without causing spalling or other damage at cracks, joints, and other locations.

§  Must be capable of correcting the pavement profile and providing proper transverse cross-slope.

§  The effective wheelbase must be at least 12 feet (3.6 m):  a set of pivoting tandem bogey wheels at the front of the machine and at the rear. Wheels that travel and track in the fresh cut pavement must be provided.

§  The center of the grinding head must not be further than 3 feet (0.9 m) forward from the center of the back wheels.

§  Must be configured such that it does not encroach on traffic movement outside of the work area in adjacent lanes

§  Must be designed to remove all grinding residue. Grinding residue is not permitted to flow across lanes being used by the traveling public.

Requirements for surface measuring equipment (profiler):

§  A non-contact, surface measuring device, conforming to Supplement 1058, along with ProVAL software, must be used to measure an IRI.

§  All necessary supplies must be provided to fully operate and graph the smoothness test results on the diamond ground pavement.

Contractors doing diamond grinding work must use water trucks to provide water to the grinding heads of each grinder in order to cool the diamond blades.

Construction (257.03)

The plans will designate the areas to be diamond ground.  Bridge decks, bridge approach slabs, and roadway shoulders are typically not diamond ground unless indicated on the plans or required to provide drainage.  Diamond grinding must eliminate crack or joint faults while providing positive, lateral drainage by maintaining a constant cross-slope between grinding limits in each lane.  Adjacent ramp lane grinding must be transitioned as required from the mainline edge to provide positive drainage and an acceptable riding surface.

The diamond grinding operation must result in pavement that conforms to the typical cross-section and the requirements specified for the final surface finish.  Faulting at joints and cracks must be eliminated and the overall riding characteristics be restored within the limits specified.  To accomplish the smoothness required, diamond grinding may not be required on 100 percent of the existing pavement surface.

In faulted pavement, the rear slab will be lower than the forward slab (in the direction of traffic), thus creating a step or bump. Contractors will grind the pavement in the opposite direction of normal traffic flow so the step is cut first and the remainder of the slab can be feathered out. During initial grinding operations, the profiler must test the pavement surface as soon as the concrete has been ground full-lane width.  This initial testing is to aid the Contractor in evaluating the grinding methods and equipment being used.  Subsequent to the initial testing, the Contractor must run daily profiles of each day's grinding the following work day.

All dust and residue generated as a result of grinding must be immediately removed.  Dust cannot be allowed to blow across traffic lanes, into gutters, or into drainage structures.

Final Surface Finish (257.04)

The final surface finish produced should be a longitudinal corduroy-type texture.  The peaks of the ridges of this corduroy-type texture are to be approximately 1/16 inch (1.5 mm) higher than the grooves.  There must be 53 to 57 evenly spaced grooves per foot (174 to 187 per meter).

Figure 257.C – Surface Texture Left by Diamond Grinding

The pavement surface must be tested by the Contractor with an approved profiler device that provides electronic copies of the pavement profiles which are compatible with ProVAL software.  The Contractor must produce a riding surface that does not exceed an IRI of 95 inches per mile or any localized surface deviations in excess of 0.4 inches in 25 feet. 

The Engineer is to witness testing of the pavement’s wheel paths.  Wheel paths are to be located every 3 feet (0.9 m); measured transversely, inside all lane edges; and parallel to the centerline. The profiler is to be maintained at the wheel path at all times when testing the pavement. 

Figure 257.D – Profile Measuring Device

Figure 257.E – Typical Profile Trace

The Contractor must regrind any 0.10 mile section of pavement with an IRI greater than 95 inches per mile.

The Contractor must provide traffic control and survey stationing necessary for all profiling.  Profile measuring equipment is to stop within 1 foot (0.3m) of any existing pavement not ground, any pressure relief joint or any approach slab to a bridge.

Inspection should include spot testing the pavement to verify that transverse joints and cracks are flush with the adjacent pavement.  If opposite sides of a joint or crack are within 1/16 inch of each other, it is considered flush.  The cross-slope should be checked with a 12 foot straightedge for deviations greater than 1/4 inch.  Straightedge requirements do not apply to areas that have not been ground.

Method of Measurement (257.05)

Measure pavement grinding by the square yard (square meter) of pavement ground and accepted.  The quantity of pavement grinding will be determined by multiplying the width specified on the plan by the total length of finished pavement surface measured in the field. This excludes bridge decks, approach slabs, and other areas designated by the Engineer.

Basis of Payment (257.06)

Payment is full compensation for the furnishing of labor, materials, tools, equipment, and incidentals and for doing all work involved in grinding the existing surface, removing residue, cleaning the pavement, and testing with a profiler that conforms to the plans and specifications. 

Documentation Requirements - 257 Diamond Grinding Portland Cement Concrete Pavement

1.        Check and document pavement grinding equipment prior to use in order to assure compliance as to width of diamond grinding head, number of grooves per foot, vacuum system, etc.

2.        Check and document pavement smoothness testing equipment for compliance. Obtain ODOT certification of the equipment from the Contractor.

3.        Perform and document spot testing of ground pavement for surface tolerances.

4.        Obtain and document profiling test results.

5.        Measure length of ground pavement and use the plan width to calculate area for pay.

6.        Document area calculations on CA-D-3A, CA-D-3B, or other approved form.

258 Dowel Bar Retrofit

General

This is a rehabilitation technique that is normally specified to restore load transfer at faulted transverse cracks in older concrete pavements.  It has also been used in new construction when dowel bar installing equipment on a concrete paving machine inadvertently fails to install dowels at contraction joints.  Standard Construction Drawing BP-2.6, Dowel Bar Retrofit, is to be followed when constructing this item of work.

Description (258.01)

The work involves the following:

1.        Sawing the proper size slots across transverse cracks.

2.        Cleaning the slots.

3.        Injecting a silicone, caulking filler to seal the crack and filler board.

4.        Placing a smooth dowel bar 1-1/2 inch in diameter with appropriate dowel chairs, expansion caps, and 1/2 inch thick filler board in each slot.

5.        Filling the slot with one of the specified cementitious patching materials.

6.        Consolidating, finishing, and curing the cementitious patching material.

7.        Establishing a joint by sawing.

Equipment (258.03)

Equipment for sawing slots in the pavement must be power driven gang type assemblies with diamond saw blades that are capable of sawing a minimum of three slots at a time.  Saws must not damage the existing pavement.

Figure 258.A – Slot Sawing Equipment

Figure 258.B – Slot Sawing Equipment

Jack hammers used to remove concrete from the sawed slots must be less than a 30 pound (13.6 kg) class.

Abrasive blast equipment used to clean debris from the slots must be capable of removing the saw slurry and other foreign material from the exposed surfaces of the sawed slot. A clean, newly exposed concrete surface free of spalls, laitance, and all contaminants detrimental to achieving an adequate bond will be left.  If wet blasting is used, ensure water blasting pressure with abrasives in the water is 10,000 psi (690 bar) or less.

Construction (258.04)

The Engineer must mark the transverse cracks to be retrofitted with dowels.  The Contractor will provide the spray paint.  The Contractor must position the slots as shown in Standard Construction Drawing BP-2.6, Dowel Bar Retrofit.

 The sawing must be done to the specified width of 2-1/2 inches (65 mm) and to a length, as needed, to allow the centering of the dowel at the transverse crack.  The slot must be sawed deep enough to ensure that the dowel, when installed with a 1/2-inch tall prefabricated chair, is level and located at mid-depth in the concrete slab.  The slots must be parallel to the centerline of the pavement.  The Contractor may make multiple parallel saw cuts within the 2-1/2 inch width to facilitate removal of concrete and to provide a level surface for the feet of dowel bar chairs.  Six slots are to be cut in each lane at each crack, three slots at 1 foot (0.3 m) centers in each wheel path, as shown in BP-2.6.

Figure 258.C – Saw Cuts for Three Slots

Figure 258.D – Concrete Removal by Light Weight Jack hammer

Once sawing is complete, the concrete is carefully removed from the 2-1/2 inch slot using lightweight jack hammers (30 pounds [13.6 Kg] or less).  Once concrete is removed, traffic must be kept off of the slots until patching material is placed and cured. 

It is permissible to do all of the sawing within an area and open the pavement for a period of time, but once the concrete is removed traffic must be prohibited from using the pavement.

Once concrete is removed from the sawed slots to the proper depth, cleaning of the slots can begin.  Inspection should include checking the slot depth to ensure the bottom of the slot is level and to the proper depth.  Cleaning must be done by approved abrasive blasting (wet or dry) which will produce a rough surface on the sawed faces of the slots.  The Contractor’s abrasive blasting operation must not damage the surrounding pavement.  Do not allow the Contractor to begin abrasive blasting operations unless reasonably available engineering controls are implemented to limit fugitive dust.  The Contractor must conform to state, regional, and local government agency requirements regarding the control of dust generated by blasting operations.

Figure 258.E – Dry Abrasive Blasting

Figure 258.F – Blowing Out Slots - Air Blast

After cleaning the slots, caulk cracks at the bottom and sides of the slot with silicone material.  The purpose of caulking is to keep the patching material from entering the crack when placed in the slot.  The caulking material must be forced into the crack under pressure.  Care must be taken to be neat and not contaminate the cleaned slot face in adjacent areas.

Figures 258.G – Dowels Installed in Prepared Slots at Transverse Cracks

Next, dowel bars are placed into the prepared slots.  Inspectors must ensure the Contractor follows these dowel placing requirements:

Dowels must be 1-1/2 inches (13 mm) in diameter and 18 inches (460 mm) long.  The dowel is to be centered on the crack. Dowels must be epoxy coated steel or fiber reinforced polymer.

Coat each dowel with a thin coating of new light form oil just prior to installation in the slot.

Place an expansion cap on each end of the dowel prior to placing it in the slot.

Two dowel bar chairs are required for each dowel bar.  The chair is to be placed parallel to the pavement surface.  Normally the two dowel chairs are attached to each dowel prior to installation into the slot.  These dowel chairs must firmly hold the dowel bar centered in the slot at the proper elevation of 1/2 inch (13 mm) from the slot bottom.  Inspectors must reject any chair design that allows movement of the dowel bar during placement of the patching material.

The dowel must have the 1/2-inch (13 mm) thick preformed filler board centered on the dowel to maintain the crack across the slot, as shown in BP-2.6.  This filler board must fit tight around the dowel and extend to the bottom and to the edges of the slot.  The filler board must be maintained in a vertical position and be tight to all edges during placement of the patching material.  Use the silicone caulking material on the bottom of the preformed filler to keep the patching material from flowing under it.   The filler board must extend from the bottom of the slot to the surface of the pavement.  If the filler board shifts during placement of the patching material, the Contractor must redo the installation at no additional cost.

Once the dowels are in place at the proper location, the Contractor must make several passes of an air blast throughout each slot to provide a dust free slot for adequate bonding of the patch material.  

Next, the patching material is mixed, placed, and cured per the material manufacturer’s directions.  The patching materials specified are prepackaged, proprietary, cementitious materials which may allow the use of a certain amount of aggregate of a certain grading to be blended with each bag.  The Contractor must provide one of the approved patching materials listed on the Department’s Qualified Products List (QPL). 

Figure 258.H – Portable Mortar Mixer

Figure 258.I – Filling Slots with Patching Mix

The patching materials are mixed in the field with a portable mixer.  When the material is placed into the prepared slot, it must be consolidated with an internal vibrator approved by the Engineer.  The excess patching material is screeded off flush with the adjacent pavement.  The surface is cured per the manufacturer’s directions; however, a minimum cure time of 4 hours (or as directed by the Engineer) is required before placing any vehicle loads on the repair. 

Figure 258.J – Internally Vibrating Patch

Figure 258.K – Patches Cured with Spray Cure

Method of Measurement (258.05)

The Department will measure the quantity of Retrofit Dowel Bars by the actual number in the complete and accepted work.

Basis of Payment (258.06)      

Payment is full compensation for furnishing all materials including paint; sawing and cleaning the slots; installing dowel chairs, dowels, bond breaker material, dowel bar end caps, sealant/caulking material, filler material, and patching material.

Documentation Requirements - 258 Dowel Bar Retrofit

1.        Mark and document the locations of dowel bar retrofit.

2.        Check and document equipment for compliance prior to commencing work.

3.        Check and document all dowels (diameter, length, and epoxy coating) and dowel hardware (expansion caps, dowel chairs, and 1/2-inch wide, preformed filler board) for compliance.

4.        Document all materials used (sealant, patching material, etc.).

5.        Document compliance to specification requirements (slot location, width and depth of slot, cleaning, dowel placement, chair placement, patch mixing and placement, curing, etc.).

6.        Document the number of slots performed each day for payment.

7.        Pay the unit bid price for Dowel Bar Retrofit.

300 Bases

301 Asphalt Concrete Base

Description (301.01)

This work consists of constructing a base course of aggregate and asphalt binder, mixed in a central plant, and spread and compacted on a prepared surface.

The requirements of Item 401 apply, except as modified by this specification. 

Composition (301.02)

The Contractor shall furnish aggregate for the mix that conforms to the following gradation:

Sieve Size

Total Percent Passing

2 inch (50 mm)

100

1 inch (25.0 mm)

75 to 100

1/2 inch (12.5 mm)

50 to 85

No. 4 (4.75 mm)

25 to 60

No. 8 (2.36 mm)

15 to 45

No. 16 (1.18 mm)

10 to 35

No. 50 (300 µm)

3 to 18

No. 200 (75 µm)

1 to 7

The Contractor may use reclaimed asphalt concrete pavement (RAP) or reclaimed asphalt shingles (RAS) as per 401.04.  The Laboratory will establish the JMF according to 401.02.

Asphalt concrete is sampled and tested by the Contractor at the asphalt plant.  The Contractor quality control tests should be based on the random number procedure found in the Contractor’s QCP. Random number along with sample tonnage location and time should be recorded on the TE-199. Contractor tests are used for pay if they are verified by District testing.  See 403.06 for sampling details.

Spreading and Finishing (301.04)

The Contractor must notify the Engineer at least 24 hours before the start of paving.  Spreading equipment must conform to 401.12 specifications.  The Contractor must submit in writing, the model of asphalt spreader to be used, provide a certification statement that all required modifications have been made, and provide a signature.  The maximum compacted thickness of any one lift is 6 inches.  The uncompacted lift thickness will be greater than 6 inches by approximately 1/4 inch per inch of compacted thickness. 

The minimum air temperature required for paving 301 base is 40 °F (5 °C).  The minimum mixture temperature when delivered to the paver is 250 °F (120 °C).  When using warm mix asphalt, the minimum temperature is 230 °F (110 °C).  The mixture temperature should be checked at a minimum of four times per day or more if necessary.  The temperature should be documented in the project records.

Hauling

Hauling must conform to specification 401.11.

The Contractor must use trucks for hauling asphalt concrete that have tight, clean, smooth metal beds from which the entire quantity of mixture is discharged smoothly into the spreading equipment.

If transporting hot asphalt concrete at prevailing air temperatures below 50 °F (10 °C), or if the length of haul exceeds 20 miles (32 km), ensure that all truck beds are insulated to maintain workable mix temperature and ensure that all covers are fastened to exclude the wind.  Do not exceed a distance of 50 miles (80 km) from the asphalt concrete plant to the paving site, unless specified by the Department.

Compaction

Compaction must conform to specification 401.16.

Compact the mixture uniformly using a combination of both steel and Type I pneumatic tire rollers which conform to 401.13.  Do not use a spreading rate that exceeds the total of the specified capacities of the rollers in use.  A pneumatic tire roller is required for compaction of base mixes.  The type and number of rollers must be documented in the project records.

Ensure that the maximum compacted depth of any one layer is 6 inches (150 mm) and the temperature of the mixture, when delivered to the paver (not to the job site), is a minimum of 250 °F (120 °C).

Example: Roller capacity and placement rate.

A contractor is using one 3-wheel roller, one vibratory roller with 66-inch drums (both vibrating), and one Type I pneumatic tire roller to compact a 5-inch thick mat using material with a Laboratory conversion factor of 2.0 tons per cubic yard.

From Table 401.13-1, the following is the capacity of the rollers the Contractor will use:

·         Three-wheel = 700 sq yd/hr

·         Vibratory r oller = 2 drums x 66 in x (15 sq yd/in of width) = 1,980 sq yd/hr

·         Type I pneumatic roller = 1,000 sq yd/hr

·         Maximum roller capacity = 700 + 1,980 + 1,000 = 3,680 sq yd/hr

[(3,360 sq yd/hr) X (9 ft²/sq yd) X (5 in) X (1 ft/12 in)] X (1 yd³/27 ft³)   = 511.11 yd³/hr. 

511.11 yd³ X 2.0 tons/Yd³ = 1,022.22 tons per hour maximum placement rate.

Spreading and Surface Tolerances (301.05)

Spread the mixture at the rate calculated using the specified thickness, the compacted width of the pavement course being placed, and the weight-to-volume conversion factor established in 401.21.  Maintain the actual rate of spreading the mixture within a tolerance of ±5 percent.

Do not exceed 3/8 inch (10 mm) in surface variation from the edge of a 10-foot (3 m) straightedge.  Surface variations include bumps and depressions.  If using Item 301, Asphalt Concrete Base, as a subbase for a rigid pavement or base, do not exceed a variation of 1/4 inch in 10 feet (6 mm).

Example: Determining the required placing rate per station (RPRS).

A contractor is placing a 5-inch uniform mat of asphalt concrete pavement whose Laboratory conversion factor is 2.0 tons/cubic yard.  The required placing rate (RPRS) in tons of material per station for a 12-foot wide mat is:

RPRS      = [Volume of asphalt in cubic yards] x [Lab Conversion Factor]

= [{100 ft per station X 12 ft X (5 in ÷ 12 in/ft)} ÷ 27 ft³/ yd³] X 2.0 tons/yd³

                = 37.04 tons/station

Documentation Requirements - 301 Asphalt Concrete Base

1.        Document condition of base material at the time of paving (example: primed 304, clean and dry concrete, etc.).

2.        Obtain JMF for the project.

3.        Obtain letter from Contractor stating paver to be used and certifying that all modifications have been made as required.

4.        Document tack or prime used along with source and quantity used versus required.

5.        Document surface and air temperatures.

6.        Write location (station), date, and time on asphalt plant tickets.  Tickets should be totaled daily and initialed with the calculator tape attached.

7.        Document lift thickness, mat width, weather conditions, surface tolerance checks, equipment problems, mat problems (segregation, tearing, tenderness, etc.), spreading rate, roller coverage, and any other issues or observations made during paving operations.

8.        Obtain and document temperature of the mix at project site and place this information on ticket of load checked.  This should be done a minimum of four times daily or any time temperature is in question.

9.        Document the kind of rolling equipment and maximum tons per hour allowed.  See the example, “Roller Capacity and Placement Rate.”

10.     Calculate and document the quantity of material placed for payment.

11.     Document on form CA-FP-4 or other approved forms as needed.

302 Asphalt Concrete Base

Description (302.01)

This work consists of constructing a base course of aggregate and asphalt binder, which is mixed in a central plant, and spread and compacted on a prepared surface.  This item is similar to 301 and requires the same level of field inspection and documentation.

The requirements of Item 401 apply, except as modified by this specification.

Composition (302.02)

The Contractor shall furnish aggregate for the mix that conforms to the following gradation:

Sieve Size

Total Percent Passing

2 inch (50 mm)

100

1-1/2 inch (37.5 mm)

85 to 100

1 inch (25.0 mm)[1]

68 to 88

3/4 inch (19.0 mm)[1]

56 to 80

1/2 inch (12.5 mm)[1]

44 to 68

3/8 inch (9.5 mm)[1]

37 to 60

No. 4 (4.75 mm)

22 to 45

No. 8 (2.36 mm)

14 to 35

No. 16 (1.18 mm)

8 to 25

No. 30 (600 µm)

6 to 18

No. 50 (300 µm)

4 to 13

No. 200 (75 µm)

2 to 6

[1]           Provide aggregate to retain a minimum of 7 percent of the material on each of these sieves.  This requirement applies to the gradation of the JMF and the mix production according to Item 403.

The Contractor may use reclaimed asphalt concrete pavement (RAP) or reclaimed asphalt shingles (RAS) as per 401.04.  Asphalt concrete is sampled and tested by the Contractor at the asphalt plant.  Contractor tests are used for pay if they are verified by District testing.  See 403.06 for sampling details.

Spreading and Finishing (302.04)

The Contractor must notify the Engineer at least 24 hours before the start of paving.  Spreading equipment must conform to 401.12 specifications.  The Contractor must submit, in writing, the model of asphalt spreader to be used, provide a certification statement that all required modifications have been made, and provide a signature.  The compacted thickness should be a minimum of 4 inches and a maximum of 7-3/4 inches.

The minimum air temperature required for paving 302 base is 40 °F (5 °C).  The minimum mixture temperature, when delivered to the paver, is 250 °F (120 °C).  When using warm mix asphalt, the minimum temperature is 230 °F (110 °C).  The mixture temperature should be checked a minimum of four times per day or more if necessary.  The temperature should be documented in the project records.

Hauling

Hauling must conform to specification 401.11.

The Contractor must use trucks for hauling asphalt concrete that have tight, clean, smooth metal beds from which the entire quantity of mixture is discharged smoothly into the spreading equipment.

If transporting hot asphalt concrete at prevailing air temperatures below 50 °F (10 °C), or if the length of haul exceeds 20 miles (32 km), ensure that all truck beds are insulated to maintain a workable mix temperature and ensure that all covers are fastened to exclude the wind.  Do not exceed a distance of 50 miles (80 km) from the asphalt concrete plant to the paving site, unless specified by the Department.

Compaction

Compaction must conform to specification 401.16.

Compact the mixture uniformly using a combination of both steel and Type I pneumatic tire rollers which conform to 401.13.  Do not use a spreading rate that exceeds the total of the specified capacities of the rollers in use.

Ensure that the compacted depth of any one layer is between 4 and 7-3/4 inches and the temperature of the mixture, when delivered to the paver (not to the job site), is a minimum of 250 °F (120 °C).

Example: Roller Capacity and Placement Rate

A contractor is using one 3-wheel roller, one vibratory roller with 66-inch drums (both vibrating), and one Type I pneumatic tire roller to compact a 5-inch thick mat using material with a Laboratory conversion factor of 2.0 tons per cubic yard.

From Table 401.13-1, the following is the capacity of the rollers the Contractor will use:

·         Three wheel = 700 sq yd/hr

·         Vibratory roller = 2 drums x 66 in x (15 sq yd/in of width) = 1,980 sq yd/hr

·         Type I Pneumatic Roller = 1,000 sq yd/hr

·         Maximum roller capacity = 700 + 1,980 + 1,000 = 3,680 sq yd/hr

[(3,360 sq yd/hr) X (9 ft²/sq yd) X (5 in) X (1 ft/12 in)] X (1 yd³/27 ft³) =

511.11 yd³/hr. 

511.11 yd³ X 2.0 tons/Yd³ = 1,022.22 tons per hour maximum placement rate.

Spreading and Surface Tolerances (302.05)

Spread the mixture at a rate calculated using the specified thickness and the compacted width of the pavement course being placed, and the weight-to-volume conversion factors established in 401.21.  Maintain the actual rate of spreading the mixture within a tolerance of ±5 percent.

Do not exceed 3/8 inch (10mm) in surface variation from the edge of a 10-foot (3 m) straightedge.  Surface variations include bumps and depressions.  If using Item 302 Asphalt Concrete Base as a subbase for a rigid pavement or base, do not exceed a variation of 1/4 inch in 10 feet (6 mm).

Example: Determining the Required Placing Rate per Station (RPRS)

A contractor is placing a 5-inch uniform mat of asphalt concrete pavement whose Lab conversion factor is 2.0 tons/cubic yard.  The required placing rate (RPRS), in tons of material per station, for a 12-foot wide mat is:

RPRS      = [Volume of asphalt in cubic yards] x [Lab Conversion Factor]

= [{100 ft per station X 12 ft X (5 in ÷ 12 in/ft)} ÷ 27 ft³/ yd³] X 2.0 tons/yd³

                = 37.04 tons/station

Documentation Requirements - 302 Asphalt Concrete Base

1.        Document condition of base material at the time of paving (example: primed 304, clean and dry concrete, etc.).

2.        Obtain JMF for the project.

3.        Obtain letter from Contractor stating paver to be used and certifying that all modifications have been made as required.

4.        Document tack or prime used along with source and quantity used versus required.

5.        Write location (station), date, and time on asphalt plant tickets.  Tickets should be totaled daily, initialed, with the calculator tape attached.

6.        Document lift thickness, mat width, weather conditions, surface tolerance checks, equipment problems, mat problems (segregation, tearing, tenderness, etc.), spreading rate, roller coverage, and any other issues or observations made during paving operations.

7.        Obtain and document temperature of the mix at project site and place this information on ticket of load checked.  This should be done a minimum of four times daily or any time temperature is in question.

8.        Document the kind of rolling equipment and maximum tons per hour allowed. See example, “Roller Capacity and Placement Rate.”

9.        Calculate and document the quantity of material placed for payment.

10.     Document on form CA-FP-4 or other approved form.

304 Aggregate Base

Materials (304.02)

All of the material requirements for 304 are located in section 703.17. This section allows for the use of the following five material types:

1.        Crushed Carbonate Stone (CCS).

2.        Crushed gravel.

3.        Crushed Air-Cooled Blast Furnace slag (ACBFS).

4.        Granulated slag (GS).

5.        Open Hearth slag (OH).

Crushed Carbonate Stone (Limestone) Used for 304

If Crushed Carbonate Stone (CCS) is used, the material must meet the gradation and physical requirements in 703.17.  In rare cases these materials become soft after a rain event or over the winter.

Crushed Gravel Used for 304

If crushed gravel is selected for use as aggregate base, it must be manufactured from material retained on the 1/2-inch (12.5 mm) sieve.  It must meet the gradation and physical requirements shown in 703.17.  At times this material lacks some fine material and becomes unstable.

Crushed Air-Cooled Blast Furnace Slag Used as 304

If Air-Cooled Blast Furnace slag is selected for use, ensure that the material meets the requirements of Supplement 1027.  This material can cause environmental concerns.  The gradation and physical requirements are detailed in 703.17.

Granulated Slag Used for 304

If Granulated slag is selected for use, the material must meet the requirements of 703.08.

Open Hearth Slag Used as 304

If Open Hearth slag is selected for use, ensure that the material meets the gradation and physical requirements of 703.17 and the requirements of 703.14 which include:

1.        Deleterious Substances.

2.        Identification of OH slag.

3.        Verification of Tufa performance.

4.        Aging and stockpiling requirements.

5.        Expansion testing.

Before Spreading (304.03)

1.        Sample the material to be used.

a.        Develop a moisture density curve per Supplement 1015.

2.        Material Moisture.

a.        The material must have reasonably uniform moisture content.

b.        Prior to spreading, use moisture content no less than 2 percent below optimum moisture. 

c.        Add water to the stockpile, if required.

3.        Minimize segregation. 

a.        If segregation occurs, mix or re-grade the stockpile.

Spreading (304.04)

1.        Do not spread on frozen surfaces.

2.        Do not use frozen material.

3.        Do not exceed a compacted lift thickness of:

a.        Eight inches (200 mm) when using vibratory rollers greater than 12 tons (11 metric tons). 

b.        Six inches (200 mm) with vibratory rollers weighing 10 to 12 tons (9 to 11 metric tons).

c.        Four inches (100 mm) with no vibratory roller. If the Contractor is compacting with a vibrating plate compactor, the maximum lift thickness is 4 inches.  If the Contractor is compacting with a roller without any vibration, the maximum lift thickness is 4 inches.

d.        Can use a lighter roller with equivalent centrifugal force.

e.        Centrifugal force is the weight with vibration.

f.         Contractor needs to document that the roller weight requirements are met.

4.        Place in equal lifts when the specified thickness exceeds 8 inches (200 mm).

a.        Example: if a 12-inch lift is specified, place in two 6-inch lifts.

Figure 304.A – Spreading 304 with a Dozer and Spreader Box

Figure 304.B – Spreading 304 with an Asphalt Paver

5.        Use self-propelled spreading machines.

a.        Capable of placing the 304 material true to line and grade.

b.        Use a dozer with a spreader box or an asphalt paver.

                                                               i.      This operation prevents segregation.

                                                              ii.      If an area appears to be segregated, take in place gradation tests according to Supplement 1090.

                                                            iii.      Contractor is only allowed to use dozers without spreader boxes, graders, or hand-placing methods when the total area of the aggregate base is 2,000 square yards or less or in small areas.  Do not take in-place gradation tests in small areas.

Figure 304.C – Spreading 304 with a Dozer May Result in Segregation

Figure 304.D – Spreading 304 with a Grader May Result in Segregation

Compaction (304.05)

Figure 304.E – Adding Water to 304 Prior to Compaction

Figure 304.F – Compacting 304 with Vibratory Roller

1.        Add water or dry out the material.

a.        To bring material to within 2 percent of the optimum moisture content.

b.        Add water or dry the 304 prior to compaction.

                                                               i.      Material is too dense to add water after compaction.

c.        Maintain moisture during compaction.

d.        Uniformly apply water throughout the lift.

e.        Reduce when unstable.

2.        Compact immediately after spreading.

Figure 304.G – Construct a Test Section

Figure 304.H – Perform the Compaction Tests

3.        Construct a short test section. 

a.        Compaction testing according to Supplement 1015.

b.        Use a minimum of eight passes in the test section.

                                                               i.      Minimizes getting a false maximum.

4.        Use and adjust the vibration.

a.        Maximize density and stability.

b.        When vibration at maximum can make any material unstable.

5.        Use 98 percent for the acceptance in the production area.

a.        Take three tests in the lot for acceptance.

b.        Use the average of the results.

6.        Use at least:

a.        Same number of passes and compactive effort used to obtain the test section maximum density for the production material.

                                                               i.      Increases passing results in the production area.

7.        At a minimum, use eight passes in the production area.

a.        Increases passing results.

8.        Reduce minimum passes if detrimental.

a.        Do not over roll, it may cause cracking.

9.        Construct a new test section when:

a.        Material changes.

b.        Supporting materials change (e.g., change from natural soil to cement stabilized subgrade).

10.     Check production material density.

a.        Before or after the finishing operations.

11.     Maintain the surface so the texture is:

a.        Reasonably uniform.

b.        Aggregate firmly keyed.

c.        Hauling on the 304 will “Un-key” the material.

12.     Scheduling 304 operations.

a.        Cover the aggregate base with the next pavement layer prior to the end of construction season.

b.        If the Contractor doesn’t pave before the end of construction season, then the Contractor is responsible for contamination, damage, and instability of the base, subgrade, and underdrains.

13.     Provide drainage and maintain the material according to 203.04.A.

a.        Maintain the cross-slope.

b.        If it rains or material sits over the winter.

                                                               i.      Dry the 304 and subgrade.

                                                              ii.      Obtain and maintain stability and density.

Finished Surface (304.06)

1.        Finished surface should not vary:

a.        More than 3/8 inch (10 mm).

                                                               i.      From a 10-foot (3 m) straightedge parallel to the centerline.

b.        Or more than 1/2 inch (13 mm).

                                                               i.      From a template conforming to the required cross-section. 

2.        Contractor to furnish straightedges, templates, or other devices.

Checks of the Depth

1.        At the beginning of the spreading operation.

a.        Contractor must adjust the spreader.

                                                               i.      Produce sufficient loose depth to meet plan compacted thickness.

1.        Determined after compaction.

                                                              ii.      Make occasional checks.

1.        During the spreading to ensure uniform depth after compaction.

b.        Purpose is to control spreading.

                                                               i.      Need not be recorded. 

2.        After fine grading.

a.        Make depth checks.

                                                               i.      At 500-foot (150 m) intervals.

                                                              ii.      Extended to 1,000 feet (300 m) if depth is consistent and meets plan depth.

b.        Some variation in depth is expected.

                                                               i.      Tolerance of 3/4 inch (19 mm) between individual measurements.

c.        If consistently less by any amount.

                                                               i.      Requirements have not been met.

                                                              ii.      Take corrective action.

d.        If individual measurement.

                                                               i.      Less than 3/4 inch (19 mm) of plan depth.

1.        Make measurement within 100 feet (30 m).

2.        If greater than plan thickness.

a.        Satisfactory. 

3.        If less than plan thickness.

a.        Make checks at additional locations.

b.        Define deficient area.

c.        Require correction.

e.        Record all depth measurements.

                                                               i.      With station locations.

                                                              ii.      Place in the project records.

Checks of the Width

1.        Measurements of the width of base.

a.        Need not be made prior to placement of overlying courses because the width of base can readily be verified.

2.        After the overlying pavement is placed, make a visual verification of the base width.

a.        If it conforms to or exceeds the plan width, file a statement in the project records.

Documentation Requirements - 304 Aggregate Base

1.        Materials.

2.        Roller weights.

3.        Record lift thickness.

4.        Segregation.

5.        Roller passes.

6.        Perform the compaction tests according to S-1015.

7.        Verify cross-section and thickness.

8.        In-place gradation tests according to S-1090, if required.

9.        Obtain weight ticket, if required. Tickets should be totaled with initialed and dated tape attached.  Convert to cubic yards (cubic meters) as per 304.07 of the C&MS.

10.     Pay and measure according to 304.07 and 304.08.

11.     Document on the CA-EW-12, CA-D-1, and CA-D-2.  Do not duplicate the information on these forms unless necessary.

305 Portland Cement Concrete Base

Construction (305.02)

When constructing this item, the requirements of 451 apply with the following exceptions:

1.        Reinforcing mesh required by 451.08 is not required in concrete base.

2.        Provide dowels at transverse contraction joints in mainline pavement, ramps, acceleration/deceleration lanes, or collector/distributor lanes.  Dowels are not required in shoulders for mainline pavement, ramps, acceleration/deceleration lanes, or collector/distributor lanes unless the transverse contraction joint is located within 500 feet of a pressure relief joint.

3.        Construction joints are not to be placed within 6 feet of another parallel joint.

4.        The curing application rate for the membrane forming, curing compound for concrete base is 200 square feet per gallon (5 square meters per liter) instead of what is specified for 451 and 452 pavement described in 451.11.

5.        The surface finish for concrete base is broom dragged in either the longitudinal or the transverse direction to provide a uniform, gritty surface texture to the satisfaction of the Engineer.  Tining per 451.10 is not required.

6.        Surface smoothness variations for concrete base are not to exceed 1/4 inch in 10 feet (6 mm in 3 m).

7.        Station numbers as required in 451.10 are not required for concrete base.

Method of Measurement (305.03)

The concrete base must be field measured and the area of pavement placed be calculated for payment in square yards (square meters).  The area is determined the same as 451 or 452 pavement.

The pavement width for payment will be based on the plan typical cross-section, plus any additional widening that has been directed by the Engineer.  The length will be field measured along the centerline of the roadway or ramp.

Determine thickness of the base conforming to 451.18.A.

Basis of Payment (305.04)

Pay a reduced price for base found deficient in thickness according to 451.19.A.  There is no additional payment for a concrete base thicker than that shown in the plans.  Pay for accepted quantities at the Contract price per square yard (square meter).

Documentation Requirements - 305 Portland Cement Concrete Base

1.        Document subgrade/subbase preparation.

2.        Document contraction, expansion, and longitudinal joints dowel as well as tiebar sizes, type, coating, support, placement, and spacing.

3.        Document forms set 100 percent bearing, correct alignment and grade, rigid, clean, and oiled.

4.        Document length of lap and clearance maintained on steel mesh.

5.        Document contraction joint spacing, dowels oiled, dowel assembly tie wires removed, number and size of pins used to hold dowel assembly, and alignment of dowels.

6.        For slip form construction document:

·         Test section results.

·         Approval of slip form paver.

·         Alignment of dowels using MIT Scan-2.

·         Corrective action as required.

7.        Document concrete placement including all quality control testing, method of placement, finishing, curing (type and amount), and weather conditions.

8.        Document use of HIPERPAV software, time of sawing, and depth and width of sawed joints.

9.        Document coring for thickness verification and results.

10.     Record results of beam breaks and opening to traffic.

11.     Measure length and width for pay.

12.     Document on CA-D-3A or CA-D-3B or other approved forms.

308 Asphalt Treated Free Draining Base

This Item was not included in the 2013 Construction and Material Specifications.  Refer to the 2006 Construction Inspection Manual of Procedures for information on this Item.

320 Rubblize and Roll

Description (320.01)

This work consists of breaking up existing, rigid, concrete pavement using a rubblize and roll method to provide a base material for the placement of new asphalt concrete pavement.

Materials (320.03)

Filler material may be needed to correct grade after the concrete pavement has been rubblized.  The Contractor must furnish materials conforming to Item 304 in order to fill depressions 1 inch (25 mm) or greater in depth.

Equipment (320.03)

The Contractor must use a self-contained, self-propelled unit of either the resonant frequency type or the multiple head breaker type for rubblizing the exposed concrete pavement.  There are specific equipment requirements for each type of breaker.  The Contractor must provide documentation showing that the proposed equipment meets those requirements.  Refer to C&MS 320.03 for specific details.

A vibratory roller is required and must have a total weight of at least 10 tons.  The Contractor must provide documentation for the roller, if needed by the project, to verify total weight.

Construction Details (320.04)

Saw Cutting

The Contractor must make a full-depth saw cut to cut load transfer devices at existing joints on ramps or on the mainline pavement where the rubblizing abuts concrete pavement or approach slabs that are to remain in place permanently, or temporarily, for maintenance of traffic.

Test Section

The Contractor is required to rubblize a test section before beginning full-scale operations.  The Engineer will designate the test section area.  The Contractor will rubblize the test section per the specification requirements.  At the direction of the Engineer, the Contractor will excavate a test pit to check the particle sizes of the rubblized concrete throughout the depth of the slab.   Based on the Engineer’s determination, the rubblizing operation may proceed or additional test sections and test pits may be required in order to obtain the required particle sizes. 

The test pit can be refilled using the excavated material and additional 304 aggregate to bring the final surface to the required grade.  The test pit can be rolled at the completion of the test section, or later, during full operation.

Excavate at least one test pit, at the location designated by the Engineer, for each production day or every 7,040 square yards (5,886 m2), whichever is greater.  Throughout the rubblizing, the Engineer may require additional test pits, as necessary.

Control and Operating Speed

The Contractor is required to adjust the speed of the rubblizing operation in order to maintain the correct particle sizes.  If the Contractor does not consistently obtain the specified particle sizes, the Engineer may require another test section, test pit, or additional passes to ensure compliance.  The correct particle size is of critical importance to obtaining a suitable base material, details of the particle size requirements can be found in 320.04.

 Filling and Compacting

Leave steel reinforcement in place in the rubblized pavement.  Reinforcing steel may rise to the surface during the rubblizing or rolling operations. However, cut off any exposed steel reinforcement to below the surface and remove it from the site.   

The rubblized pavement must be compacted with two passes of the vibratory roller operated in the vibratory mode at a speed not to exceed 6 feet (1.8 m) per second. 

Depressions 1 inch (25 mm) or more in depth, below the immediate surrounding surface that form as a result of rubblizing, compaction, or steel reinforcement removal, must be filled with filler aggregate conforming to Item 304 or other Department accepted well graded aggregate that will compact.

Excess filler material must be leveled off so that it is level with the surrounding area.  Compact filled depressions with the same roller and compactive effort as previously described.

Restrictions

Traffic is not allowed on the rubblized pavement before the initial asphalt concrete base and intermediate courses are in place. 

The Contractor must structure operations so that no more than 48 hours elapse between rubblizing the pavement and placing the initial asphalt concrete course.  In the event of rain during the 48-hour period, the Engineer may waive this time limitation to allow sufficient time for the rubblized pavement to dry to the Engineer’s satisfaction. 

If the Engineer waives the time limitation, cease rubblizing the pavement until the Engineer allows paving to resume.

Method of Measurement (320.05)

The Engineer will measure rubblize and roll by the number of square yards (square meters). 

The Engineer will use the actual width of the existing concrete pavement and will measure the length along the centerline of each roadway or ramp.

The Engineer will measure the filler aggregate by the number of cubic yards (cubic meters) furnished, placed, and compacted.

Documentation Requirements - 320 Rubblize and Roll

1.        Document that equipment being used meets the specifications.

2.        Document the location and particle size determination for each test section. 

3.        Document where rubblizing is being performed (station-to-station), particle sizes obtained, cutting of reinforcing steel, addition of filler aggregate, roller speed and passes, and any other observations or issues during the operation.

4.        Measure the width of the actual existing pavement and the length along the centerline of each roadway. Calculate square yards for payment.

5.        Measure the filler aggregate and calculate the number of cubic yards placed and compacted.

6.        Document using form CA-D-3A or other approved forms.

321 Cracking and Seating Existing Plain Concrete Pavement

Description (321.01)

This work consists of breaking up an existing, non-reinforced concrete pavement using a cracking and seating method to provide a stable base for the placement of new asphalt concrete pavement. 

Equipment (321.02)

The Contractor must use equipment that is capable of producing the desired crack pattern without extensive spalling or excessive shattering.  Extensive spalling is considered at depths greater than 1-1/4 inches.

Whip hammers cannot be used.

The Contractor must use a 50-ton pneumatic tire roller that conforms to the requirements of 204.06 (Proof Rolling) to seat the cracked concrete slabs. Pneumatic tire towing equipment is required to move the roller forward and backward along predetermined lines.  The Contractor shall provide information to verify the roller meets the specification requirements.

Construction Details (321.03)

The Contractor should provide positive provisions, in addition to 107.07, to contain any flying debris during cracking operation.

The Contractor must demonstrate to the Engineer the ability of the selected equipment and procedure to produce the desired crack pattern by cracking at least three, but no more than 5 existing concrete slabs.  The Contractor shall furnish and apply water to dampen the cracked concrete to enhance visual determination of the crack pattern during the test section process.  The Contractor must make adjustments to the energy or striking pattern to maintain the desired crack pattern.

The Contractor must provide a crack pattern of 4-foot by 4-foot (1.2 m X 1.02 m) segments.

There may be instances where the existing slab is already cracked into segments by age and traffic.  In these cases, the Contractor must further crack the slabs to obtain a maximum 5-foot and minimum 3-foot dimensions, both transversely and longitudinally. 

The breaking equipment shall not be allowed to affect slabs within 1 foot of another break line, a joint, or the edge of the concrete slab. 

At least once a day, the Contractor must apply water to a check section to allow verification of a satisfactory crack pattern.  When the crack pattern differs from required, the Contractor must make adjustments to the operation in order to bring the crack pattern into compliance.

The Contractor must roll the cracked pavement until the all of the concrete pieces are seated with at least two roller coverages.   The seated pieces cannot rock or move after seating. 

The Engineer will determine the maximum number of coverages of the roller on the test section to ensure proper seating of segments without damage to the concrete.

Before placing asphalt concrete, the Contractor must remove all loose pieces of concrete that are not fully seated.  All voids must be repaired by applying 407 Tack Coat, filling with asphalt concrete, and compacting as directed by the Engineer.

Traffic is not allowed on the cracked concrete before the initial asphalt concrete base and the intermediate courses are in place.

Documentation Requirements - 321 Cracking and Seating Existing Plain Concrete Pavement

1.        Document that equipment being used meets the specifications.

2.        Document the location and crack pattern obtained from the test section.  Include any additional test sections and results.

3.        Document where cracking and seating is being performed (station-to-station), segment sizes obtained, roller coverages, addition of tack and asphalt to fill voids, and any other observations or issues during the operation.

4.        Measure the width of the actual existing pavement and the length along the centerline of each roadway and calculate square yards for payment.

5.        Document using form CA-D-3A or other approved forms.

400 Flexible Pavement

401 Asphalt Concrete Pavements – General

General Description

General requirements for mix production and construction of asphalt concrete pavement courses are included in Item 401.  The Contractor responsibilities in supplying and placing a quality asphalt pavement are summarized in C&MS 401.01 paragraph 3. 

Other specific requirements for flexible pavement production, quality control, and mix design are included in Item 402 Asphalt Concrete Mixing Plants, Item 403 Asphalt Concrete Quality Control and Acceptance, and Item 441 Contractor Mix Design and Quality Control - General.  Requirements for the specific pavement courses are found in the specifications under the contract item designation (301, 442, 446, 448 etc.). 

The quarterly posting of Supplemental Specification (SS) 800 on ODOT’s website is used to update the C&MS.  Plan sets list the SS800 that is in effect for every project.  Check the plan set to ensure you are using the correct SS800 posting since specifications change over time. 

Asphalt concrete is a mixture of aggregate and asphalt material.  The asphalt material used in these mixtures has a relatively high viscosity at normal temperatures. It is necessary to heat the aggregate and asphalt material to permit mixing, placing, and compacting.

Asphalt concrete may be used in new construction as the entire pavement structure or it may be used with other materials in a layered pavement structure.  Extensive use of asphalt concrete is made for rehabilitating existing pavements by resurfacing or widening and resurfacing.  Asphalt concrete is particularly adaptable to this type of work, where disruption of normal traffic flow must be kept to a minimum.  Although written with reference to new construction, the instructions contained herein also apply to rehabilitation construction.

Asphalt concrete mixtures are produced in a central proportioning and mixing plant.  At the plant, aggregate is dried and heated to the mixing temperature and combined with the specified asphalt material.  On completion of mixing, the asphalt mixture is discharged directly into trucks, or conveyed to surge bins or silos, from which trucks are loaded for transport to the project.

Asphalt concrete is placed by mechanical pavers. After it is placed, the mixture must be compacted using the proper compaction equipment before it cools and becomes unworkable.

Field Quality Control Supervisor (FQCS)

Item 403.03 requires the Contractor to provide a FQCS, who is a company employee who is at the paving site and is responsible for the quality of the asphalt being placed.  The FQCS is responsible for identifying problems (see C&MS 401.01 paragraph 3) with the placement and immediately works to make corrections.  Address all field quality issues with the FQCS and document all problems and all corrections.  When the FQCS is not responsive, refer the problem to the Engineer for resolution.  An FQCS can have his approval removed for failure to perform his duties.  A list of approved FQCS personnel, by contractor,  can be found on ODOT’s website.

Field Inspection

The Inspector assigned to the placing of asphalt concrete should closely observe the placing of each type of mixture for indications of deficiencies in the mixture composition.  If the mixture appears to be deficient in any of the following respects, notify the District plant monitor and the FQCS immediately, and note on the Inspector’s Daily Report.  The Engineer should be consulted when there is mix deficiencies that need addressed.  In some cases, production should cease immediately. 

Requirements for Mix Design, Materials, Rap, Mixing Plants (401.02 through 401.05)

A Job Mix Formula (JMF) is submitted by the Contractor using the contract mix specifications for the contract asphalt concrete (446, 448, etc.).  The Laboratory must provide conditional approval of all JMFs before production of any asphalt concrete.  A JMF is not considered “approved” until it has been used successfully in the field.  The JMF provides the proportions of the aggregates and Reclaimed Asphalt Pavement (RAP), Reclaimed Asphalt Shingles (RAS), and binder content, along with the optimal compaction temperature for the asphalt mix.  This information is used in quality control for production and in field inspection.  The Contractor quality control requirements for asphalt concrete are provided in Item 403.

Laboratory personnel must inspect and approve the mixing plant that will be used by the Contractor prior to the production of any asphalt concrete.  Specification Item 402 and Supplement 1101 provides detailed requirements for asphalt mixing plants.

Weather Limitations (401.06)

There are specific requirements for air and surface temperatures in Item 401.06 that must be met before paving can start.  In all cases, the existing surface to be paved must be dry and with weather conditions that allow proper handling placement and compaction.  Table 401.06-1 provides minimum surface temperature requirements based on the thickness of the course being placed. 

The air temperature must be 40 °F for all surface courses.  For any surface course using a polymer modified asphalt binder the surface and air temperature must be at least 50 °F. 

TABLE 401.06-1

Course Thickness

Minimum Surface Temperature

3.0 inches (75 mm) and over

36 °F[1]

(2 °C[1])

1.5 to 2.9 inches (38 to 74 mm)

40 °F

(5 °C)

1.0 to 1.4 inches (25 to 37 mm)

50 °F

(10 °C)

Less than 1.0 inch (25 mm)

60 °F

(16 °C)

Variable Intermediate, 0 to 3.0 inches (0 to 75 mm)

40 °F

(5 °C)

[1]           Instead of 36 °F (2 °C), use a minimum air temperature of 40 °F (5 °C) if paving on an aggregate base or subgrade.

This specification prohibits Contractors from scheduling placement of a surface course with a polymer modified asphalt binder after November 1, regardless of the pavement or air temperature.  Although the Department, in certain circumstances, may allow the placement of a polymer modified surface course after November 1, this practice should be avoided if at all possible.  Ensure the Engineer has concurred with any decisions that conflict with this prohibition.  Where the Engineer does allow paving after November 1, ensure the Contractor is taking all precautions to ensure complete roller coverage before the mix cools below the laboratory, compaction temperature stated on the approved JMF.

Surface temperature measurements should be taken using the following procedures:

·         When taking a reading in the sun, place the thermometer on the pavement and then shade that area with a clipboard, cardboard, or other available shading material.  Take the temperature reading after approximately 3 minutes.  The intent is not to shade the area to allow it to cool, but to protect the thermometer from obtaining a false reading due to direct exposure to the sun. 

·         The surface temperature should not be taken under the only shade tree or at the only sunny (unshaded) spot on the project.  The surface temperature should be taken at a representative area. 

·         The surface temperature should be taken in the lane to be paved and not the adjacent berm.

·         On Portland cement concrete pavements where flexible repairs have been performed, the surface temperature of the Portland cement concrete will be the governing temperature. 

·         A new surface temperature should be taken when the existing pavement surface material changes (asphalt concrete to Portland cement concrete or vice versa) to ensure that the new surface meets the minimum temperature specification.  If this specification is not met, paving operations must be discontinued until the surface reaches specification temperature.  Paving operations may be moved to a different area of the project where the surface meets minimum specification temperature.

Placing thin, surface courses at temperatures near the applicable temperature limits may require the Contractor to employ special precautions to produce a satisfactory surface.  These precautions include avoiding paver stops, keeping the rollers close to the paver, adding additional rollers, and providing proper insulation for the trucks hauling the material. 

It is the Department’s responsibility to instruct the Contractor to stop paving operations in the event of rain.  It is the Contractor’s responsibility to stop plant production.  If the Contractor will not stop placement, notify the Engineer.

During a rain event, a load of material in the process of being dumped into the paver may be placed with the requirement that the rollers follow closely behind the paver and a construction joint is formed at the end of the run.  Do not allow waiting trucks to be dumped and placed.  The material in the waiting trucks will retain sufficient heat for proper placing and compacting for an hour or more depending on the ambient temperature.  Water can be kept from accumulating on the covers of the trucks and draining into the asphalt mixture by raising the truck beds slightly.  These loads may be placed when conditions improve if the asphalt temperature is acceptable and the surface being paved is in a reasonably dry condition.

Notification (401.07)

The Contractor is required to notify the Engineer at least 24 hours before starting paving on a project.  It is a recommended practice for the Engineer to call for a meeting to discuss the material and equipment to be used.

Hauling (401.11)

Included in the specifications (401.11) are the requirements concerning the condition of the vehicles used to haul asphalt concrete mixtures and the distance the mixture may be transported.

Check the trucks for compliance with the specifications as they arrive at the paving site.  In particular, look for the following:

·         The bed tarp is in good condition and covers the bed.  Contact the testing office if any concerns.

·         Small portions of the load are not isolated from the mass on projections such as extensions over cabs.

·         The load is discharged evenly, without surging in the paver hopper, and without jogging the vehicle when it is in contact with the paver.

·         As the bed is raised, it does not come in contact with the paver.

·         Uniform contact between the truck and the paver is maintained as the paver pushes the truck during unloading.

·         Excess release agent is not being used on the truck bed.

·         Diesel fuel is not being used as a release agent.  If diesel is smelled in a load notify your testing office.

·         Insulation is required when the air temperatures are below 50 °F or haul length exceeds 20 miles, check to see that all trucks are properly insulated and permit only approved trucks to be loaded.

Notify the Contractor when deficiencies are found.  When corrections are not satisfactory and difficulties persist, the vehicle in question should be removed from the project.  Contact the testing office with any issues.

The Contractor is to provide a place off the project for cleaning trucks when hauling polymer modified asphalt binder mixes or when material is sticking to the truck bed.  If the sticking to the truck bed is determined to be from excessive cooling of the mix, the Engineer will require an insulated bed. 

Each load of asphalt is delivered to the project accompanied by a plant ticket with the load tonnage.  The plant ticket must contain the date; project number; load gross, tare, and net weight; the JMF and material identification; producer name; producer location or plant number; and the time the truck left the plant. When the load is accepted at the paving site, the Inspector records the placement location and initials the ticket.

Spreading Equipment (401.12)

Asphalt pavers shall be self-propelled, mechanical spreading and finishing equipment, provided with a screed assembly capable of distributing the material to the full width of the lane being paved.  The type of equipment suitable for spreading asphalt concrete depends on the particular paving operation to be performed: mainline, widening, berm, intersections, and whether the pavement course to be placed is base, intermediate, or surface.  Spreading equipment requirements are stated in 401.12. 

The Contractor should use means and methods approved by the asphalt spreader manufacturer consisting of, but not limited to, any combination of chain curtains, deflector plates, or other such devices that will eliminate segregation.

Certain pavers require modifications.  C&MS Item 401.12 lists the pavers that require modification.  The Contractor must submit a certification statement to the Engineer which states that the paver to be used is modified and approved as per 401.12.

Pavers that leave ridges, indentations, or other marks in the surface shall not be used.  The Engineer shall determine whether a paver is providing an acceptable asphalt mat that is ready for compaction.  See C&MS 401.01 Paragraph 3.

The basic types of pavers found in current practice are described in the following paragraphs.

Floating Screed Asphalt Paver

A standard asphalt paver consists of a tractor with a receiving hopper, a conveying and distributing system, and a floating screed.  The screed is essentially a rectangular trowel which floats on the surface of the asphalt mixture. The tractor pulls the screed by means of two shafts, or arms, hinged to each side of the tractor. The thickness of placed material is regulated by adjusting the angle of the screed with respect to the arms.  This adjustment causes the screed to rise or fall until a condition of equilibrium is reached.  Vibrating or tamping devices on the screed maintain a uniform flow of mixture under the screed. A heating system is provided to bring the screed to operating temperature at the beginning of work and to maintain proper screed temperature in cool weather.

The paver must have an automatic control system that maintains the screed in a constant position relative to grade, profile, and cross-slope references.  These references must be capable of controlling the screed position independent of irregularities in the underlying surface and the paver operation. 

When paving in excess of the nominal paver width, only a screed extension with full auger extensions and the ability to heat should be used.  Strike-off plates may only be used on adjacent berm areas. 

Look for the following items when considering approval:

·         Equipment must have sufficient size, power, and stability to receive the asphalt concrete material without erratic operation. 

·         Equipment must be capable of placing the material accurately in regard to line and grade.

·         Asphalt concrete must be fed uniformly across the width of the screed without surges (which produce corresponding roughness in the finished surface).

·         Asphalt concrete mixture behind the screed must have a uniform appearance across the full width of the course.

It is the Contractor’s responsibility to make any necessary adjustments in the paver operation.  The Inspector, however, should be familiar with the working of the paver, the effect of wear on paver operation, and the effect of various paver adjustments on the placing operation.

Offset Blade Strike-Off Paver

Where the use of a standard paver cannot be used due to irregular areas or size, special paver types can be approved by the Engineer.  One type is the offset blade strike-off paver.  This type of paver has a receiving hopper that feeds asphalt to a side-mounted strike-off blade.  The tractor to which the hopper is attached operates on the surface adjacent to the area being paved.  The blade is attached to the tractor and can be adjusted for width, elevation, and cross-slope.  These pavers are used to place asphalt concrete for pavement widening, berm paving, pavement repairs, and other applications where a relatively narrow width is to be placed. 

Rollers (401.13)

Compaction of asphalt concrete is governed by 401.16, 446.05, or 448.03  depending on the contract item designation.  Item 446 is accepted by density testing and the roller selection is at the discretion of the Contractor, not governed by 401.13.  This is also the case for 448, when it is accepted by field density testing using Supplement 1055.  Acceptance by density testing allows the Contractor to select the type and number of rollers needed to obtain proper compaction, and thus, receive full compensation.  When compliance with 401.13 is not required, rollers must be inspected for general working condition, leaks, and suitability.  The Department retains the right to reject the use of rollers which are not in good repair or are not designed to do the required work fully and satisfactorily.

Where Item 448 is not accepted by density testing, and for Items 301 and 302 Asphalt Concrete Base, the requirements of 401.13 apply.

For asphalt concrete items requiring compliance with item 401.13, all rollers must be inspected for conformance with the specifications before paving begins.

Steel drums and rubber tires used for compaction should have the necessary accessories to prevent adhesion to the mixture. They should be kept moistened with water, water containing a detergent, or water containing an approved release agent.  Excessive use of liquid should be prohibited.

Pneumatic tire rollers must be self-propelled, reversible units with vertical oscillation on all wheels, on at least one axle.  The Contractor should determine the tire inflation pressure necessary to meet the specified minimum contact area and contact pressure requirements.  The Contractor should furnish the tire manufacturer’s charts or tabulations to the Engineer for verification of the required inflation pressure.  Tire inflation pressure should be maintained within 5 pounds per square inch (35 kPa) of the required pressure.

Approval of specialized equipment proposed for compaction, in areas inaccessible to the specified rollers, should be based on obtaining equal results.

Tables 401.13-1 through 401.13-3 list the specific requirements for rollers.

TABLE 401.13-1 ROLLER CAPACITY

Roller Type

Maximum Capacity

Square Yards per Hour (m²/hr)

Tandem

700 (600)

Three-Wheel

700 (600)

Trench

15 per inch width (13 per 25 mm width)

Pneumatic Tire, Type 1

1000 (850)

Pneumatic Tire, Type 2

700 (600)

Vibratory, Vibrating Roll

15 per inch width (13 per 25 mm width)

Vibratory, Static Roll (not vibrating)

3 per inch width (3 per 25 mm width)

TABLE 401.13-2 STEEL WHEEL ROLLERS

Roller Type

Three-Wheel

Tandem

Vibratory
Static

Trench

Total weight, tons

(metric tons)

10

(9)

8 to 12

(7 to 11)

8 to 12

(7 to 11)

-

Compression rolls, pounds per inch width (kN/m), minimum

300

(53)

200

(35)

120

(21)

300

(53)

TABLE 401.13-3 PNEUMATIC TIRE ROLLERS

Type I

Tire size, minimum

9.00 ´ 20 in (229 ´ 508 mm)

Wheel load, minimum

5000 lb (2250 kg)

Average tire contact pressure, minimum

85 psi (590 kPa)

Type II

Tire size, minimum

7.50 ´ 15 in (191 ´ 381 mm)

Wheel load, minimum

2000 lb (900 kg)

Average tire contact pressure, minimum

55 psi (380 kPa)

Conditioning Existing Surface (401.14)

Cleaning the Surface

The surface on which an asphalt concrete course is to be placed must be free from material accumulations that would contaminate the mixture, prevent bonding, or interfere with placing operations.  The surface of the existing pavement should be inspected before the paving operation begins, and should be cleaned of all foreign material, particularly dust, in accordance with 401.14.  The surface should be checked a short distance in front of the paver to ensure that the surface has not become contaminated during the construction operation.  A dirty or very dusty surface reduces the ability of the tack coat to bond, resulting in a potential slippage plane between the existing surface and the asphalt overlay.

Maintenance of Previously Constructed Surfaces

Prior to placing asphalt concrete on a pavement course constructed under the same contract, the condition of this previously approved work should be inspected.  Where the approved subgrade or pavement course has become loosened, rutted, or otherwise defective, the deficiency must be corrected before the placing of a subsequent course is permitted.  Hauling of materials over an asphalt concrete base course, for example, may cause cracking when there is not sufficient pavement thickness to carry heavy loads or where excessive deflection occurs over soft areas developed in the subgrade.  Where cracking of the pavement occurs in such a case, the strength due to slab action is destroyed, and the affected material must be removed and replaced after correcting the cause of the failure. 

Tack Coat

A tack coat is applied to an existing surface and to a new asphalt surface in preparation for the next course.  Tack materials are asphalt emulsions conforming to C&MS Item 702.  The following types are allowed 702.04 RS-1, SS-1, SS-1H, CRS-1, CSS-1 or CSS-1H, or 702.13.

The plans will indicate where tack is to be placed.  In the case where the plans do not specify tack between an intermediate and surface course, this specification makes that application a requirement. 

Coating Vertical Faces

The specification requires all vertical faces that will be in contact with an asphalt course to be coated with asphalt material of a type specified in 401.03 in order to improve the bond to the new asphalt concrete course.  This includes gutters, curbs, catch basin castings, etc., and the vertical face of an existing pavement.  Due to the small quantity of material involved, approval of the asphalt material for this purpose may be based on field inspection.  The results of this inspection are recorded on the Inspector’s Daily Report, with the material identified as to type, grade, manufacturer, and quantity used.

Correcting Existing Surface Irregularities

In some resurfacing contracts, a quantity of asphalt concrete may be specified in the plans for making spot corrections, or for placing a continuous intermediate course to correct the cross-slope and profile of the existing pavement, as directed by the Engineer.  This operation should be controlled closely to ensure that the best possible riding quality is obtained in the completed pavement.

Spot corrections, when provided for in the plans, are made to correct irregularities such as cross-slope or profile problems.  Spot corrections can include a leveling or “scratch” course.  These corrections are made prior to placing the intermediate or surface course.  Unless specifically detailed on the plans, the Engineer will locate deficiencies in the existing surface requiring spot correction and notify the Contractor of the required corrective measures.  Interior edges of spot patching may be irregular, but outside edges must conform to the specified edge alignment.  All spot corrective work must be completed to the satisfaction of the Engineer before the intermediate or surface course is placed. 

Intermediate course of asphalt concrete can be specified to correct minor irregularities in the existing pavement surface. Spot correction may be needed prior to placing the intermediate course. The intermediate course should not be used to correct major deficiencies.  Inspect the placing of the intermediate course to assure that all deficiencies have been corrected satisfactorily.  For intermediate courses where the profile or cross-slope is not specified on the plans, the profile of the new course should provide for a smooth riding surface, and the cross-slope should be uniform on all tangent sections and should vary uniformly in transition sections into superelevated sections.  For an intermediate course where the profile or cross-slope is specified, the new course should conform to the required profile and cross-slope, within the specified limits.  The procedure for checking the profile and cross-slope is given in Section 401.19.

Spreading, Finishing, and Night Work (401.15)

Field Inspection

During asphalt paving, careful observation of the mat behind the paver and the rollers is required to ensure a quality and durable finished pavement.  The Contractor’s FQCS is responsible for the entire paving operation from surface preparation to paving.  The Contractor is required to control and take prompt corrective action when the mat being placed is not free of any defect within that Contractor’s control.  Any deficiency in the mat should be brought to the attention of the FQCS.  Record the deficiency and the action taken by the FQCS.  If the FQCS does not make changes to remedy the defects, notify the Engineer.  An FQCS can have his approval removed for failure to perform his duties. The following examples are defects or problems during pavement preparation or paving that should be observed and corrected.

Tack Coat

Tack coats are used to bond asphalt layers together to create a monolithic pavement structure.  All of the pavement layers need to act as one in order to effectively resist the shear and tensile stresses induced by traffic.  The tack coat keeps the pavement layers from sliding over one another and prevents layer delamination.  If the tack coat is insufficient, the pavement life will be reduced.  The proper application of tack coat is often overlooked in the field. 

Tack must be applied in a fine, even spray that covers the entire pavement.  Tack application that appears “stringy,” spider-webbed,” streaked, or ridged is unacceptable and should not be included for pay.  Refer to Item 407 in the MOP.

Pavements to be tacked must be properly cleaned using power brooming or street sweeping.  Where surfaces have been milled, residual dust is a major problem, thus, creating a bond breaker between the existing asphalt and the tack coat.  This leads to excessive truck tire pick-up.  Additionally, the tack coat must be given time to “cure” so tire pick-up is minimized.

Picture 401.15.A&B – Improper Tack Application

Picture 401.15.C – Uniform Tack Coverage

Segregation

Segregation can be caused by asphalt plant processes, improper truck loading, hand placing and raking, and paver operation. Segregated areas are susceptible to raveling over time and rapid pavement deterioration.  Only a dense, uniform surface texture is acceptable. 

When an asphalt mat is segregated, the coated coarse and fine aggregate particles physically separate from each other.  Segregation can appear in a cyclical pattern or randomly across the mat.  The aggregate in the mat should appear to be uniformly graded in size from coarse to fine, behind the paver, in the finished mat. 

End-of-load segregation occurs as cyclical V-shaped or chevron type patches in the mat.  This type of segregation is a result of improper truck loading operation at the plant that results in the large aggregate separating from the fine aggregate in the truck bed.  This generally can be controlled by changing loading operations at the plant.

Segregation must be controlled by the Contractor.  The FQCS is responsible for making changes to eliminate segregation in the mat. If the FQCS does not make changes to remedy the defects, notify the Engineer.  An FQCS can have his approval removed for failure to perform his duties. 

Picture 401.15.D&E – Examples of Segregated Mats

Picture 401.15.F&G – End of Load Segregation

Mixture Consistency and Mat Texture and Uniformity

The asphalt mixture should have sufficient cohesion to remain mounded in the vehicle during hauling, but should flow freely from the vehicle when the load is dumped.  Bumping or stopping the paver between loads, as well as uneven flow of material into the paver hopper, will likely leave bumps in the finished mat.  Trucks backing up to the paver hopper should never bump the paver; the paver should move to the truck and make contact with the rear tires.  During paving, asphalt should flow uniformly from the truck into the hopper with the quantity in the hopper being maintained at a constant level.  Sudden surges cause surface irregularities. 

The mat should have a uniform appearance across the width placed.  Streaks of differing texture and pulling or tearing of the mixture generally indicate the need for adjustments to the paver screed and extensions.  Worn screed plates can also cause streaking behind the paver.  Other causes can include low mix temperatures and mix problems.  In all cases, the FQCS is required to make changes to correct deficiencies.  If the FQCS does not make changes to remedy the defects, notify the Engineer.  An FQCS can have his approval removed for failure to perform his duties.

Picture 401.15.H&I – Lack of Mat Uniformity and Texture Problems

Picture 401.15.J&K – Screed Mark from Stopped Paver (left) and Pulling and Tearing of Mat (right)

Stability

The mixture should have sufficient stability under the rollers without excessive displacement and movement.  A bow wave in front of a roller drum is indication that the material is not stable.  Resultant small, transverse cracks after rolling are also indication that the material is tender.  Roller marks may also be an indication of an unstable mix.

Picture 401.15.L&M - Roller “Checking” Caused by Unstable Material

Picture 401.15.N&O - Roller Marks Remaining in an Unstable Material

PG (Asphalt) Binder Content

Asphalt binder is used to bind the aggregate particles together.  The mixture should contain enough PG (asphalt) binder without producing a glazed or flushed appearance under the action of roller compaction.  A flushed asphalt pavement may contain too much asphalt binder. 

Another cause of a flushed or glazed surface can be a result of opening to traffic too soon, particularly on hot summer days.  The action of traffic tires on the hot surface can draw the liquid asphalt binder to the surface causing a shiny, glazed appearance. Traffic should not be permitted on a completed surface course until the mixture has cooled sufficiently.

Picture 401.15.P&Q - Glazing or Flushing

Mixture Temperature

All asphalt paving compaction must be completed before the mixture cools below a workable temperature, generally 175 °F to 225 °F.  During inspection, the temperature of the asphalt delivered to the paver, and immediately behind the paver, must be close to the optimal compaction temperature as listed on the approved JMF.  In the case of foamed Warm Mix Asphalt this may be, in general, 0 to 30 °F  less than the JMF compaction temperature.  The breakdown roller (first roller) must compact the mat at, or near, this temperature.  Complete coverage of the breakdown roller across the mat is required to obtain uniform density.  Lower compaction temperatures are directly related to an increase in air void content, which increase the permeability of the pavement.  A high permeability pavement will fail prematurely unless specifically designed to be permeable. Even with a perfect mix design, if the mix is not properly compacted in the field, the final product will not last for its intended length of time.

Thin lift asphalt is susceptible to rapid loss of heat, and its temperature must be monitored very closely, particularly during cool weather paving. 

Any mixture that cools before it can be compacted properly should be removed and replaced. 

Monitor and record the mix temperature on a regular basis throughout the paving operation. 

Truck Cleanout

Asphalt delivery trucks are not allowed to clean out truck beds on the pavement that will be paved.  The material that remains in truck beds is cold and will not compact correctly, often causing a bump in the pavement, and likely, a future pot hole.  Spreading or broadcasting the cold material across the pavement prior to paving does not solve the problem.  Always have the Contractor designate a cleanout area and ensure truck drivers are using it.  If truck drivers continue to clean out on the road to be paved, have the FQCS address the issue.

Picture 401.15.R&S – Trucks Cleaning Out in Front of the Paver

Release Agents

Truck drivers use release agents to keep asphalt from sticking to truck beds.  Diesel fuel is prohibited to be used as a release agent in truck beds, but its use still occurs on ODOT projects.  ODOT allows the use of special asphalt release agents and maintains a list of approved products on its website.  Diesel fuel dissolves the asphalt binder and causes a soft spot in the asphalt mat, which eventually becomes a pot hole.  Any truck driver using diesel fuel must be removed from the project. Contact the testing office for assistance if needed.  The FQCS is required to take action to prevent diesel fuel used as a release agent.  Pavement areas affected by diesel fuel should be corrected by removing the contaminated material and replacing it with acceptable material.  Note: the overuse of approved release agents can damage new pavement.  Observe truck loading at the asphalt plant to ensure there is no free liquid draining from truck beds as a result of over application of any approved release agent.

Picture 401.15.T&U - Soft Spots in the Mat as a Result of Diesel Fuel used as a Release Agent

Moisture

Variations in the moisture content of the aggregate fed to the plant, or an erratic production rate, may result in an excess of moisture in the asphalt concrete mixture.  This can cause slumped or flattened loads accompanied by considerable bubbling or steaming of the mixture.  In extreme cases, the PG binder material may separate from the aggregate and collect in a film over the surface of the load.  This condition is unacceptable and is sufficient cause for rejection of the load.  Excess moisture may cause streaks of excess PG binder material to appear as the mixture is spread.  Report moisture problems to the Plant Monitor and the FQCS.

Contamination

An asphalt concrete mixture can become unsatisfactory due to contamination of the PG binder material, the aggregate, or the mixture itself.  Contamination of the PG binder material, either in shipment or in storage at the plant, has the most serious effects.  Contamination of the PG binder material may remain undetected until a quantity of mix is produced, at which time a marked change in the odor, consistency, or appearance of the mixture in the truck or in the paver hopper indicates that contamination has occurred.  When these changes are noted, observe the mixture carefully as it is being placed and compacted.  Report changes in the mixture to the FQCS and ensure there is follow-up.

Night Paving

Luminance

When nighttime paving is required, no work can proceed without an approved and operating lighting system.  This work consists of furnishing, installing, operating, maintaining, moving, and removing nighttime lighting to illuminate construction work areas for night work.  Night work is defined as work performed from 30 minutes before sunset to 30 minutes after sunrise.

An illuminated zone of at least 5-foot-candles is required in the immediate vicinity of all paving equipment and at least 1-foot-candle at 25 feet.  Item 401.15 provides these specific requirements.  The Engineer must approve the lighting system based on measured luminance readings.  The Contractor must provide a photometer that can measure the luminance levels at the specified foot-candles with measurements taken 20 inches above the roadway.

Luminance measurements can be required by the Contractor at any time as requested by the Engineer.  The Contractor must provide luminance readings at any change in the approved lighting configuration.  Any corrections and deficiencies must be made within 1 hour or the Engineer is required to shut down the construction.

Light sources shall be positioned so they do not interfere with, impede, or cause glare for motorists.  Light cannot be pointed at adjacent properties.  Luminaires must be kept clean and bulbs replaced immediately.  Asphalt pavement placed during nighttime operations should be reviewed and inspected in the daylight for mat problems like segregation, smoothness, etc.  The results and observations of daylight reviews should be used to make corrections and adjustments to the paving procedures in order to correct and prevent substandard operations and unacceptable asphalt pavement.

Picture 401.15.V&W - Night Paving Lighting

Material Transfer Vehicle (MTV)/Material Transfer Device (MTD)

Many jobs require paving during night hours to avoid lane restrictions during peak traffic hours.  The Department maintains a website that details those roadways that cannot have lane closures during daylight hours.  It can be difficult to see mat deficiencies (e.g., segregation) during night paving due to limited lighting and shadowing. Undetected segregation has been known to be a problem; therefore, the Department requires the use of an MTV/MTD with paver hopper insert or remixing paver for night paving under the following conditions:

The project plans include more than 1 mile of continuous paving (measured through the bridges) and the surface course is being paved.

Or for intermediate course paving when PN 401 is included in the project proposal.

An MTV, MTD, or remixing paver must be a machine specifically made to eliminate segregation of asphalt mats.  There are MTVs and MTDs that merely transfer material from the truck to the paver and do not mechanically remix the material prior to discharge to the paver hopper.  These machines are not allowed.  The Contractor must provide manufacturer’s information to prove that the MTV/MTD proposed for use on the project has a mixer/agitator mechanism that consists of either segmented, anti-segregation, re-mixing augers, or two full-length longitudinal paddle mixers specifically designed for the purpose of re-mixing.  Longitudinal paddle mixers shall be located in the paver hopper insert.

Remixing pavers specifically made to eliminate asphalt segregation are acceptable alternatives to an MTV/MTD.

In all cases, the selected equipment must eliminate segregation, provide a uniform temperature throughout the mixture, and limit temperature differentials to less than 25 °F (14 °C) across the mat.

Before the start of paving, the Contractor shall provide a method for measuring the mat temperature differentials, and a method of inspection for segregation, that will be used during paving operations.  Measuring mat temperatures can be performed using an infrared thermometer or special equipment specifically designed for this purpose, such as the Pave IR system.  There should be a regular daylight inspection of the mat placed the previous night to ensure there are no areas of segregation that could not be seen during night paving operations.

Equipment that that does not consistently eliminate physical segregation and/or does not meet the temperature differential requirement should not be used on the project.  Notify the FQCS of deficiencies of the equipment and ensure a remedy is put in place.

Picture 401.15.X&Y - Remixing Paver (Left) and Material Transfer Vehicle (Right)

Possible Corrective Actions

Specification Item 401.15 requires the Contractor to, “Remove and replace, or otherwise correct, any portion of the pavement course found to be defective in surface texture or composition before or after compaction in a manner satisfactory to the Engineer.” The Engineer will make a determination about whether a defective pavement must be removed or can remain in place with some repairs.  The following methods may produce satisfactory results when the work is properly performed by sufficiently skilled workers.  All corrective methods must be approved by the Engineer.

Where removal of material is required or to correct a low area, saw the patch area to neat lines.  Remove the asphalt to the full-depth of the defective course and coat the surface of the of the patch area and butt joints with approved tack coat material.  Place the new mixture in the prepared patch area to the proper elevations and compact as required. 

When material must be removed to correct high areas in the surface, use a diamond grinder.  Removal and replacement of the surface course and a portion of the underlying material may be necessary in extreme cases.

Minor segregated areas in which there is insufficient fine aggregate at the surface can be corrected by a squeegee application of an asphalt binder, of the same type, used in the mixture.  An emulsion of the asphalt material, along with added fine aggregate, is also effective.  Careful use of the squeegee is necessary to fill the surface voids without leaving a surplus of the sealer on the surface. 

Compaction (401.16)

The compaction of asphalt concrete mixes is currently governed by one of two types of specifications.  A method specification is used for some asphalt concrete (301, 302, and 448 by 2005 specification and older), while most mix types (446 and 448 by 2008 specification and newer) are governed by a density requirement (446.05 and 448.03).  Supplement 1055 details the requirements of density testing for 448 mixtures.

The Job Mix Formula (JMF) provides the optimal compaction temperature for the design.  The mixture should be checked frequently to ensure the asphalt is being compacted at or near that temperature.  For foamed Warm Mix Asphalt this the filed compaction temperature may be 0 to 30 °F less than that listed on the JMF.  For asphalt concrete base pavements, refer to Items 301 and 302 for minimum allowed mix temperature.  In all cases, the mixture should not be allowed to cool below a workable temperature for adequate compaction (175 °F to 275 °F) and the majority of compaction should be accomplished before the temperature reaches 225 °F. 

Compaction (Method Specification)

This section applies to all mixes without a density specification.  Compaction of an asphalt concrete mixture using the method specification is performed by using the rollers and methods specified in 401.13 and 401.16.

The number and type of rollers proposed for use by the Contractor should be checked for compliance with 401.13.  The calculation for the roller capacity (tons per hour) should be made by the project personnel.  Documentation of the calculations and the tire manufacturer’s charts or tabulations furnished by the Contractor should be kept in the project files.  As the work progresses, the placement rate should be checked to ensure that it does not exceed the combined capacity of the rollers in use.  If the placement rate does exceed the roller capacity, the Contractor must either reduce the rate or use additional rollers. 

For compacting base mixtures, the specifications require at least one steel wheel and one Type 1 pneumatic tire roller.  This requirement must be met even though the placing rate may indicate the need for only one roller.  The intent is to ensure that each layer of base mixture will be subjected to the traffic conditioning effects of pneumatic tire rolling while the mixture has sufficient retained heat to respond without fracturing. 

For compacting intermediate or surface courses, the specifications require the use of a three-wheel roller in the breakdown position.  Ensure this requirement is met when using a method specification.

Example:

Roller capacity and placement rate.

A contractor is using one 3-wheel roller, one vibratory roller with 66-inch drums (both vibrating), and one Type 2 pneumatic tire roller to compact a 3-inch thick mat using material with a Laboratory conversion factor of 2.0 tons per cubic yard (tons/yd³).

From Table 401.13-1 the following is the maximum capacity of the rollers the Contractor will use:

Three wheel = 700 yd²/hr

Vibratory roller = 2 drums x 66 in. x (15 yd²/hr/in. of width) = 1,980 yd²/hr

Type II pneumatic roller = 700 yd²/hr

Maximum roller capacity = 700 + 1,980 + 700 = 3,380 yd²/hr

3,380 yd²/hr x (3 in ÷ 36 yd³/in.³) = 281.67 yd³/hr

281.67 yd³ x 2.0 tons/yd³ = 563.34 tons per hour maximum placement rate.

Therefore, the Contractor is limited to placing a maximum of 563.34 tons per hour using the rollers brought to the job.

Compaction (Density Acceptance)

This section applies to mixes accepted based on a density specification.  The Contractor is responsible for determining the correct roller train to ensure compaction.

For 446 and 448 asphalt accepted by density testing, only the last four paragraphs of 401.16 are applicable.

Item 446 mixtures require the Contractor to meet a specified density target.  To determine the density, ten 4-inch cores are cut from the pavement for each day of paving.  The District Test Lab determines the field density from the cores.  The Contractor can receive a bonus or deduction to the pay item based on the field densities.  Refer to Item 446 for detailed information on this process.

Supplement 1055 provides the procedure for density testing using a nuclear gauge for 448 mixtures.  This process requires the cutting of cores only to establish the correlation between core density and gauge density.   Refer to Item 448 and S1055 for details on determining density of 448 asphalt concrete.

Picture 401.16.A – Standard Steel Wheel Vibratory Roller

General Compaction Inspection

This section pertains to the compaction of asphalt concrete mixes using either the method specification or the density acceptance specification (described above).  The Inspector should refer to the last four paragraphs of 401.16 to review the common part of both compaction specifications. 

The optimum compaction conditions are present immediately behind the paver, and the greatest increase in density per roller pass occurs in this area.  It is important that the breakdown roller follows the paver as closely as possible and obtains full-coverage across the entire mat width being placed.  In general, roller coverage should begin at the edge and move toward the centerline, moving longitudinally, and overlapping each roller pass by one-half of the prior pass.  When a longitudinal joint is being made (i.e., matching a previous course), this joint should be rolled first and then preceded with the normal rolling pattern.  The specified roller pattern should be repeated uniformly, without abrupt stops or changes in direction, and the reversing points at the end of the roller runs should be staggered to reduce the possibility of forming transverse bumps.  Final rolling should remove all tire marks.

Asphalt pavement joints can be confined or unconfined.  Confined joints occur when the asphalt mixture is placed directly against a previously placed asphalt pavement or an existing pavement.  Unconfined joints are considered loose since they are not placed against any confining edge or structure.  Unconfined edges of the mat should be rolled using a steel drum roller with the roller drum hanging out over the edge approximately 6 inches.

Longitudinal joints occur where two lanes are, or will be, joined together.  For an unconfined or confined longitudinal joint, best results are obtained by using a drum vibratory roller operated in the vibratory mode with the frequency set at maximum.  Pneumatic tire rollers should not be used to do the first pass of an unconfined longitudinal joint. 

Picture 401.16.B – Rolling the Unconfined Edge

Picture 401.16.C – Rolling the Longitudinal Joint First

Joints (401.17)

Longitudinal Joints

Longitudinal joints in the surface layer shall correspond with the edges of proposed traffic lanes.  Longitudinal joints in lower layers shall be offset, as per Standard Construction Drawing BP-3.1, alternating each side of the edges of traffic lanes no less than 6 inches (150 mm).

Proper longitudinal joint construction requires the loose asphalt mixture to be placed at an extra 25 percent thickness above the confined joint material to allow for roll down and with a 1-inch to 1-1/2-inch overlap to permit proper compaction.  If the joint is being made against a sawed or milled vertical edge, the overlap can be around 1/2 inch. 

The height of the new asphalt mixture over the joint must be sufficient to permit full compaction of the material being placed before the weight of the roller begins to be carried on the adjacent construction.  This pre-compaction height must be maintained uniformly, particularly on surface courses where raveling of an unsound joint is likely to occur.  Height uniformity is achieved by continuous, automatic control of the strike off height. 

Figure 401.17.A

The paver should be operated in a straight line to provide a mat with a straight edge that can be consistently overlapped.  Excessive deviations of the edge line from a straight line are unacceptable and require trimming the edge before the adjacent material is placed.  With a good edge and proper control of the placing operation, little or no hand work is needed to form a good longitudinal joint.  The Contractor should not continuously rake the joint.  On surface courses, the Inspector must be sure that when hand raking does occur, it does not produce an irregular surface texture. 

On projects where traffic is maintained, the longitudinal joints between adjacent lanes of surface course pavement must be completed within 24 hours.  Where this time limit is exceeded, the joint should be inspected, and if the joint appears to be excessively rounded or displaced, trim the face to vertical according to 401.17.

All cold longitudinal joints are required to be sealed, as specified in 401.17, using a certified PG binder or SBR Asphalt Emulsion to provide 100 percent coverage of the joint.  Ensure the correct material is being used.  Often tack is used instead of the required material; this is not acceptable.

Picture 401.17.A – Sealing the Cold Longitudinal Joint

Transverse Joints

Transverse joints occur at any time the paving operation is stopped for the day (or night).  When placing the last load of asphalt for the day, the paver should move forward until all material is spread.  This leaves an irregular end that should be squared off by hand to form the joint.  This joint edge should be compacted thoroughly, with the rollers passing over the edge, even though this may cause some rounding or even displacement of the material in the process.  

Note that transverse joints at the beginning or completion of a project require joint construction, as detailed in the plan sheets, or in accordance with Standard Construction Drawing BP-3.1.

When the paving operation resumes, locate the point where the rounding or other departure from the profile begins, and continue the paving operation from that location in order to assure a smooth transition from one section to the other.  In some cases, trimming the joint face may be necessary.  For all surface courses, the transverse construction joint is required to be formed or cut to vertical.  All cold, transverse, longitudinal joints are required to be sealed as specified in 401.17 using a certified PG binder, SBR Asphalt Emulsion to provide 100 percent coverage of the joint, or with a certified 702.04 asphalt material at a rate of 0.25 gallon per square yard (1 L/m²).  

The Contractor must have workers and hot material available during construction of the transverse joint. Utilize alternate rolling, a 10-foot straightedge, and the addition or removal of material to produce a uniform profile.  Paving operations should not be permitted to continue until a satisfactory joint has been obtained.

Spreading and Surface Tolerances (401.19)

The specifications require the Contractor to maintain the rate of spreading of a uniform asphalt course to within ± 5 percent of what is required by the plan.  For a given uniform course, the Required Placement Rate per Station (RPRS) is calculated in tons per station and checked against the Actual Placement Rate (APR).  Determine the APR using the plant weight tickets, which accompany each load of material, and the area covered by a given number of loads.  The area to be used for the check should not be greater than 500 feet (150 m) in length and should be measured from the start of a full load of asphalt concrete to the end of a full load.  The results of these checks should be recorded on Form CA-FP-4, Bituminous Concrete Inspection. 

To establish the RPRS, the laboratory conversion factor (tons/yd³) is multiplied by the required volume of the asphalt pavement per station.  One station is equal to 100 feet.  The placement rate, in tons per station, is given by the following equations:

Calculate Required Placement Rate per Station, RPRS:

RPRS      =      [Volume of asphalt in cubic yards (yd³)] x [Lab Conversion Factor, CF (ton/yd³)]

                =      [{100 ft. per Station) x Lane Width (ft.) x Mat Thickness (ft.)} ÷ 27 ft³/yd³] x C.F. (tons/yd³)

                =      tons/station

Calculate the Actual Placement Rate (APR):

APR        =      [Material Used (Tons) ÷ (Test section length (ft.) ÷ 100 per Station)]

                =      tons/station

Calculate the % Difference between the RPRS and the APR:

% = [1 - (RPRS / APR)] x 100

Where:

RPRS is the required placement rate per station.

APR is the actual placement rate per station.

C.F. is the lab conversion factor (tons/yd³).

Example:

Determine the Required Placing Rate per Station (RPRS):

A contractor is placing a 5-inch uniform mat of asphalt concrete pavement 12 feet wide, with a Laboratory conversion factor of 2.0 tons/cubic yard (tons/yd³).   In 500 feet the Contractor used 188 tons of material (from the truck weight tickets).  Is the APR within ± 5 percent of the RPRS?

The required placing rate (RPRS) in tons of material per station:

        RPRS      =      [Volume of asphalt in cubic yards] x [Lab Conversion Factor]

                        =      [{100 ft./station x 12 ft. x (5 in. ÷ 12 in./ft.)} ÷ 27 ft³/yd³] x 2.0 tons/yd³

                        =      37.04 tons/station

This rate should be rounded off to two digits after the decimal for control purposes.

The APR in tons per station:

        APR        = 188 tons ¸ (500 ft ¸ 100 ft/station) = 37.6 tons/station

% Difference in Spreading Rate Tolerance:

% Difference =    [1 - (RPRS / APR)] x 100 = [1 – (37.04 ¸ 37.6)] x 100 = 1.49%

The Contractor’s actual spreading rate is within ± 5 percent of the required spreading rate.

Note:  This calculation can also be made on a tonnage basis instead of the “per station basis.”  Simply determine the required tons for the 500 feet and compare it to the actual tons placed.

Tons required =           [500 ft x 12 ft x (5 in ÷ 12 in/ft) ÷ 27 ft³/yd³] x 2.0 tons/yd3 = 185.19 tons

Tons used = 188

% Difference = [1 - (185.19 ¸ 188)] x 100 = 1.49%

When variations greater than ± 5 percent of the required rate are calculated, the Inspector should address the variance with the FQCS to determine a cause.  The Contractor should adjust the paver operation accordingly to bring an unwarranted variation back into tolerance.  The Inspector should immediately check the actual spreading rate when changes are made to the paving operation.  All variations in tolerance should be recorded in the Inspector’s daily report.

Depending on the nature of the material being placed, and quality of the placing operation, one to four placement rate checks per day normally will represent the material placed with a given paver.  When the work involves a series of small areas, the use of partial loads at each location makes the check impractical.  In such cases, the Inspector should determine plan thickness is being obtained. 

The placing of asphalt concrete should be closely controlled and kept as near as possible at the specified rate.  Even for a well-controlled operation, both positive and negative variations will occur.  The Contractor should not place the material at a rate greater than required since this would result in an overrun of plan quantity for which the Contractor would not be paid.  As stated in 401.21, “Method of Measurement,” the pay quantity is limited to the total weight of the item placed, converted to cubic yards (cubic meters), with no payment made for the quantity of material placed which exceeds that calculated from plan lines and dimensions. 

Checking Longitudinal Profile

For all new construction, and some rehabilitation construction, the required profile grade and pavement elevations are given in the plans.  Where a profile grade is not specified for rehabilitation construction, the profile of the finished pavement surface depends upon the profile of the existing pavement surface.  The plans may require profile correction prior to placing an overlay pavement; however, profile elevations may or may not be specified.

For construction where a profile grade is specified, the Contractor is required to set grade stakes in order to provide a reference for controlling the elevation at which the asphalt concrete is placed.  These grade stakes should be set at intervals of no more than 50 feet (15 m) on tangents and no more than 25 feet (7.5 m) on vertical curves and transition lengths of superelevated curves.  The stakes should be placed on both sides of the pavement to permit easy checking of the grade; intermediate stakes should be provided in areas of greater than normal width. 

The specifications require the completed pavement longitudinal profile does not deviate more than 1/2 inch from the plan elevation at any point.  The difference in pavement elevation may be obtained by methods such as profile levels or differences in rod readings.  Prior to placing the surface course, the Contractor must check the profile of the preceding course at 50-foot intervals and submit a tabulation of the results to the Engineer for approval.  The results should be tabulated in a convenient form, which list the following:

·         Station

·         Pavement elevation

·         Plan elevation

·         Difference

The Engineer will evaluate the Contractor’s profile check.  Approval of the profile and permission to place the surface course should be based on satisfactory completion of any corrective work needed for compliance with the profile requirement.  The approved profile check will be part of the project record. 

Checking Cross-slope (Transverse Slope)

For all new construction, and some rehabilitation construction, the required cross- or transverse slope of the asphalt concrete pavement is given either as crown or as superelevation in the plans.  Where a cross-slope is not specified for rehabilitation construction, the cross-slope of the finished pavement depends on the cross-slope of the existing pavement surface. 

For construction where the cross-slope is specified, the pavement cannot vary more than 3/8 inch in 10 feet from the required slope.  The Contractor should check the cross-slope of the pavement course being placed during the spreading operation with a 10-foot straightedge.  The Inspector should observe this operation regularly to ensure that the pavement course is being constructed substantially within the specified cross-slope limits. 

Particular attention should be given to the checking of the cross-slope on the asphalt concrete course preceding the surface course.  Where observation of the Contractor’s checking or additional checking by the Inspector reveals substantial deviations from the specified limits, corrections must be made to bring the asphalt concrete course within the specified cross-slope limits before the surface course can be placed.

Example of cross-slope check:

The plan specified the cross-slope as 0.016 foot per foot of pavement width (0.016 ft./ft.).  For a 12-foot wide lane, the pavement drops from the crown to the edge based on the rate of slope.  This vertical drop (in inches) is calculated:

0.016 ft./ft. x 12 in./ft. x 12 ft. pavement width = 2.3 inches

Therefore, if the Contractor checks the slope with a 10-foot straightedge, the vertical measurement from the pavement surface to the level straightedge is calculated:

0.016 ft./ft. x 12 in./ft. x 10 ft. straightedge = 1.92 inches

The spec requires a tolerance of ±3/8 inches (0.375 in.) on the cross-slope,  so the vertical measurement from the pavement surface to the level straightedge can be:

1.92 in. + 0.375 in. = 2.30 inches

1.92 in. – 0.375 in. = 1.54 inches

Figure 401.19.A

Checking Surface Smoothness

The required smoothness of asphalt intermediate and surface course cannot exceed 1/4 inch from the testing edge of a 10-foot (3.0 m) straightedge.  The Contractor is required to provide a straightedge that is satisfactory to the Engineer.  The Contractor should check the course being placed while the Inspector observes.  The frequency of checking depends on the nature of the work being done.  The surface smoothness should be checked closely when a transverse joint is being made, when erratic paver operation occurs, or when hand placing is required in the construction of a transverse joint.  This check is often done at the end of a paving project since many Contractors elect to use a non-contact profiler and software per ODOT Supplement 1058. 

When PN 420 or PN 470 is included, the Contractor is required to check smoothness using approved profilers and provide an analysis using ProVAL software according to S1058.

The project Inspector should determine at the beginning of the project which method the Contractor will use to check smoothness when PN 402 or PN 470 do not apply.  In the case neither of these proposal notes apply, ensure that the Contractor is regularly checking the surface behind the paver with the 10-foot straightedge.

Method of Measurement (401.21) and Basis of Payment (401.22)

Asphalt mixture is delivered to the project based on weight in tons for each load.  Payment is made in cubic yards for the specific item of work (e.g., 301, 448, or 446).  A conversion from tons to cubic yards is required.  The Laboratory provides a conversion factor (unit weight/volume) for the specific JMF being used in tons/cubic yard (tons/yd³). 

The number of tons placed and accepted is converted to cubic yards and compared to the quantity calculated from the plan lines and dimensions.  The Department will not pay for additional quantities over the plan calculated cubic yards.

Converting Tons to Cubic Yards (Cubic Meters)

After the total tonnage of material used in a pavement section has been determined, convert it to cubic yards (cubic meters) using the applicable conversion factor established in 401.21.  The conversion factor of a mix is included on the JMF and can be obtained from the District test lab.  The tonnage of material used in a pavement section is converted to cubic yards (cubic meters) as follows:

Cubic Yards = [TW ÷ CF]

Where:

TW = Total weight of asphalt placed (tons)

CF = Conversion factor (tons/yd³) or (tons/m³)

This volume should be rounded off to the nearest cubic yard (cubic meter).

Summarizing Quantities

Keep a daily summary that includes Reference Number (Pay Item), Item Number, paving location, tons used (along with the conversion to cubic yards), and the calculated pay quantity.  Add the asphalt plant tickets and keep with the daily summary.  Use an adding machine with a paper printout.  On the printout write the project number, date, Reference and Item Number, Participation Code, paving location (route, station to station, lane, etc.), and show the conversion to cubic yards.  Initial the printout and keep with the daily summary sheet.

Complete a final summary of the total quantity placed for each Reference Number.  The final summary should provide details for all separate pavement areas.  In general, separate pavement areas include different contract parts, different participation codes, physically separate roadways, and pavement areas having differing design sections (e.g., ramps). 

Pay Quantity for Uniform Course

The pay quantity of asphalt concrete with a uniform plan depth is calculated using the plan width and measured distance along the centerline.  Paving in excess of the plan width or plan length is not eligible for pay.  Excess quantity can only be paid if approved by the Engineer.

Pay Quantity for Variable (Leveling) Course

Where one to two courses of asphalt concrete is placed on an existing pavement for the correction of the profile and cross-section, the depth is variable and the pay quantity is the quantity placed as directed by the Engineer in accordance with the intent of the plans.  Placement rate checks, as described in Section 401.21, should be used to verify that the Contractor is meeting the intent of the plans. 

Documentation Requirements - 401 Asphalt Concrete Pavements-General

This section contains general requirements for inspecting and documenting asphalt concrete pavement operations.  The Inspector should record all observations regarding the placement of the asphalt mixture, in addition to the following requirements.

1.        Obtain JMF for the project.

2.        Verify the FQCS for the project.

3.        Determine and document if paver requires modification and has been modified per 401.12.

4.        Check and document roller capacities as outlined in 401.13 if required by the specification item.

5.        Document pavement surface condition, preparation, and surface and air temperatures.

6.        Document tack or prime used along with source and quantity used versus required.  Note if application is non-uniform and steps taken to correct.

7.        Document lift thickness, mat width, weather conditions, surface tolerance checks, equipment problems, mat problems (segregation, tearing, tenderness, etc.), spreading rate, roller coverage, and any other issues or observations made during paving operations.

8.        Observe and document trucks hauling material.

9.        Check for secured waterproof cover (tarp).

10.     Check for insulated truck beds for temperatures below 50 °F (10 °C) and/or if the haul exceeds 20 miles (32 km).

11.     Observe the asphalt mix in the truck and note any slumping, drain down, or blue smoke.

12.     Determine compliance with compaction requirements as per 401.16.

13.     Record asphalt mixture temperatures measured in the paver hopper and on the mat at the time of compaction.

14.     Determine and record required and actual placement rates and variance.

15.     Write location (and route), date, and time on asphalt plant tickets.  Tickets should be totaled daily, initialed, and with the calculator tape attached.

16.     Ensure samples, cores, or density readings are taken as required by item 446 or 448.

17.     Record luminance readings for night paving operations.

18.     When required, determine if MTV meets specification for remixing and mat temperature differential.

19.     Determine plan quantity for payment.

20.     Document on CA-FP-2 through 4 or other approved forms as needed.

407 Tack Coat

Description (407.01)

Tack coat is an application of liquid asphalt material on an existing pavement surface that provides a bond with a new asphalt pavement.  The bonding of pavement courses together creates a monolithic structure.  The entire pavement structure is needed to resist shear and tensile stresses caused by traffic.  The tack coat keeps the new pavement layers from sliding over the old layer (delamination).  Insufficient or poor application of tack coat reduces pavement life.  Proper application of tack coat is a key factor in producing a quality asphalt paving project. 

Materials (407.02)

The specification requires tack coat to be an asphalt emulsion conforming to 702.04, which includes types RS-1, SS-1, SS-1h, CRS-1, CSS-1, and CSS-1h; or 702.13, which includes SBR Asphalt Emulsions.  The most commonly used tack in Ohio is SS-1h.

Emulsions are classified as rapid setting (RS or CRS), medium setting (MS or CMS), or slow setting (SS or CSS).  The letter “C” in front of an emulsion type (CRS, CMS, or CSS), denotes a cationic (positively charged) emulsion.  If the emulsion type is followed by an “h” (SS-1h) it means the emulsion was made from harder base asphalt cement.

SBR asphalt emulsions are required for use on concrete pavements.  This replaces the older specification that required rubberized asphalt emulsion.

Tack is not to be diluted with water.  However, the Contractor may request dilution, and if the Department grants this request, the diluted material must have a minimum viscosity of 20 Saybolt Furol seconds.  The color of diluted tack will appear browner on application than does undiluted tack.  The color of undiluted tack will appear black at the time of application.

In some cases, Trackless Tack may be specified by the project plans.  Trackless Tacks are proprietary products that are applied like ordinary tack coats, but cure and set up very quickly, generally within 10 to 15 minutes, thus helping to eliminate tracking onto adjacent pavements.  Note:  Pick up and tracking due to the application of tack on dirty pavements is not solved merely by using Trackless Tack; pavement cleaning is still required as well as proper application.  The non-tracking characteristic of Trackless Tacks makes them very suitable where construction zones are short, for example, urban paving conditions.  The Contractor must supply the exact product that is listed in the plans.  In some cases, the plans may allow the Contractor to provide a Trackless Tack under an Experimental Feature provision.  The Experimental Feature requirements for the Trackless Tack must be followed exactly.  If the Trackless Tack provided does not perform in the field, the Contractor shall discontinue its use.  Examples of non-performance would include long cure times and tracking of the material.

Equipment (407.03)

Distributor trucks are used to apply tack coat using a tank and spray bar system.  The distributor is required to have a tachometer, thermometer, pressure gauges, and an accurate volume measuring device or a calibrated tank.  A calibrated tank means there is a dedicated measuring stick for the tank and a chart that correlates the stick reading to the volume in the tank.  The spray bar system must be fully circulating and the spray bar must be adjustable both laterally (to apply coverage to the correct width) and vertically (to adjust the spray fans). The spray bar must also maintain a constant height above the pavement surface as the load in the tank changes. 

Many distributor trucks are now computerized and automatically adjust the pump pressure/discharge (gpm) to obtain the required application rate.  However, there are many older distributor trucks still in use that require synchronization of the truck speed/RPM, the asphalt pump pressure/discharge (gpm), and the bar height to obtain the required application rate.  Where these trucks are used, the Contractor must provide charts or other information that shows truck and pump speeds that are required to obtain the application rate. 

In general, the faster the distributor truck goes, the faster the asphalt pump has to turn in order to get the same application rate that one would get at a slower speed. 

Figure 407.A – Example Application Chart for Etnyre Distributor

Spray nozzles must be matched to the material and desired application rate.  Often the standard nozzles that are installed by the manufacturer are not correct and have to be changed out.  If the Contractor cannot get complete coverage at the specified application rate, he may be using the wrong nozzles.

All nozzles have to be adjusted to 15 degrees to 30 degrees with the axis of the spray bar in order to get complete coverage. Ensure all nozzles are adjusted to the same angle and are open.  Clogged nozzles have to be cleaned or replaced.

Figure 407.B – Misaligned Spray Nozzles

The spray bar height must be adjusted to allow spray fan overlap, either single overlap or double overlap (if complete coverage is needed).  Item 407 does not specify the required overlap and it may not be required to obtain complete coverage when the specified application rate is very light.  In some cases, with light application rates, the Contractor may need to turn off one nozzle per every foot of spray bar and raise the spray bar height to get uniform coverage. 

Figure 407.C – Spray Bar Height and Fan Overlap

Distributors that cannot apply tack uniformly and at the required application rate shall be removed from the project.

Mechanical sweepers, power brooms, street sweepers, and other related equipment may be of any type that will adequately clean the existing surface prior to tack coat application.

Weather Limitations (407.04)

Apply tack in accordance with the temperature surface requirements for the pavement course being placed.  The minimum surface temperatures are provided in 401.06.  Record the surface temperature in the Inspector’s Daily Report.

Preparation of Surface (407.05)

The pavement surface must be dry and free of any foreign material accumulations that interfere with the bonding of the tack to the pavement.  This includes dust and mud, including dust from milling operations.  Excessive use of tack coat should never be a substitute for proper cleaning of pavement.  Excessive tack coat can act as lubricant, creating a slip plane between pavement layers. 

Remove all dust, loose aggregate, soil, leaves, and pieces or lumps of other foreign material using power brooms and street sweepers.  Blades and hand work may be required for heavy accumulations.  Make sure the full width of pavement to be paved is cleaned.

Although emulsified tack coat could be applied to a damp pavement, this practice is discouraged and should only be considered in certain critical circumstances where paving cannot be delayed.  Damp pavement will require additional cure time and the tack bond may not be as strong.  In the cases where paving on a damp surface is allowed by the Engineer, there should be no standing or flowing water on the surface of the pavement to be tacked.  The time to cure should be closely monitored to ensure the tack application has completely set before paving begins. 

Application of Asphalt Material (407.06)

Protection and Control of Traffic

When the Contract requires traffic to be maintained, tack coat application should not be allowed to start until the provisions of the traffic maintenance plan have been met.  Alternate movement of one-way traffic (flagger operation) must be in place before the distributor is brought into the starting position. 

Application of Asphalt Material

Only asphalt material meeting the requirements of 407.02 can be used.  Tack is shipped under ODOT’s Asphalt Materials Certification Requirements as detailed in Supplement 1032.  Weight tickets will be provided for the loads of asphalt material delivered to the project.  A weigh-back ticket must be provided after the application to accurately determine the quantity of tack used.  The weigh-back ticket provides the weight of the material left over and not used. The weight used will have to be converted to gallons based on the appropriate conversion factor for the tack.  Although the distributor is required to have an accurate volume measuring device, payment must be made using the weight tickets.

Inspect the distributor for compliance with the specifications.  The Contractor must demonstrate the use of the required volume measuring device, thermometer, and application controls.  Work should not be permitted to start if this equipment is unsatisfactory.  In addition, the approval of the distributor is based on observation of the operation and check measurements of the actual application rate, performed, as described, in the following paragraphs.

For large areas, the application rate is determined by the placement of a given quantity of an asphalt material over a known area.  The rate is calculated using the gallons (liters) indicated by the volume indicating device on the distributor, the known length of the distributor run, and the measured width that is covered.  The rate of application is considered acceptable when the measured application rate is within ±10 percent of the required rate and the tack is uniformly applied.  The application rate for small areas, where volume measurement is not practical, may be judged visually.  Note that for payment, the quantity used is based on weight tickets, not the volume measuring device on the distributor.

All of the nozzles should be angled 15 degrees to 30 degrees (depending on the manufacturer) from the axis of the spray bar, and the elevation of the spray bar should be maintained at a height that produces fully developed fans of bituminous material.

The operation of the distributor is judged by visual observation.  The quantity of material flowing from each nozzle should be uniform.  The angle of each "fan" of material with the spray bar should appear to be at the same angle as specified by the manufacturer.  The material should be applied uniformly across the width of the spray bar, with no visible streaks, and with no apparent variations in the width of spray, from the beginning to the end of the run. 

The results of the foregoing observations and checks are recorded for each distributor used on the job, together with a means of identification (license plate or equipment number) and indication of approval or non-approval.  This information is entered in the project record.

The asphalt material should be sprayed uniformly on the pavement surface.  The application must be uniform, without streaking, thin lines, or dribbles.  Streaking is caused by faulty distributor adjustment or operation.  Applications with streaking, thin lines, ridges, etc. are not acceptable.  The Contractor must be notified to make corrections by adjusting the distributor and the operation to obtain a uniform and consistent application of material across the entire width of the area to be paved.  After distributor corrections or repairs, a test strip must be prepared to demonstrate proper application.  Do not allow the continued use of equipment that cannot obtain a uniform application.

Pick-up and tracking of tack by paving equipment and trucks is to be controlled by the Contractor.  Pick-up occurs due to dirty pavement and/or insufficient cure times.  The Contractor is required to take steps to eliminate pick-up and tracking.  The only way to avoid pick-up of a tack coat is to apply the approved material on a clean pavement and allow the material to set up or cure prior to allowing any asphalt delivery trucks or traffic on the tacked lane.  This may require the Contractor to lengthen the traffic control zone to allow adequate cure time and to perform more thorough pavement cleaning.  Pick-up and tracking is a serious deficiency and can result in a poor bond.  The tracked material ends up on the roadway and can be a safety hazard. 

When tack coverage is not uniform and not corrected or there is pick-up and tracking, the Engineer should require a proper correction to the operation before continuing paving. The entire area of non-uniform coverage is considered non-specification and will be deducted from payment.

Figure 407.D – Examples of Good Applications

Figure 407.E – Examples of Bad Applications

Figure 407.F – Good Application with Tracking (Left)/Poor Application with Tracking (Right)

There may be rare occasions where traffic has to be maintained on a tacked pavement.  In such a case, the Contractor must place a cover aggregate to maintain a safe construction zone.  Cover aggregate is required to be sufficiently dry to permit adhesion of liquid asphalt.  When the cover aggregate is placed on an asphalt emulsion tack coat, the aggregate may be moist, but not to the extent that free water drains from the truck bed.

The Contractor is required to apply only the quantity of cover aggregate needed to prevent pick-up of the tack by traffic.  A typical rate for applying cover aggregate is 4 to 8 lbs/yd².

Method of Measurement (407.07) and Basis of Payment (407.08)

Determine gallons (liters) to be paid from weight tickets and weighed partial loads using Supplement 1060 and ODOT Form CA-FP-6. 

Where tack application is determined to be inadequate and non-specification, determine the number of gallons (liters) for non-payment by using the approved rate of application times the total square yards (square meters) of non-uniform application.

Cover aggregate is included in the bid price for the tack coat.

Documentation Requirements - 407 Tack Coat

1.        Measure and document surface temperature.

2.        Document surface preparation (sweeping, cleaning) and condition of surface just prior to tack application.

3.        Document the temperature of material as delivered to the project.

4.        Document equipment used and conformance to specifications.

5.        Calculate and document rate of application and comparison to required rate.

6.        Document the use of any cover aggregate.

7.        Document any issues with application (streaks, lines, ridges) and actions taken to correct the issue.

8.        Document areas of non-uniform application and payment deductions.

9.        Calculate and document, for pay, the number of gallons applied per 407.08, 407.09, and 109.01.

10.     Use form CA-FP-6 and other approved forms to document the tack application and calculations.

408 Prime Coat

Description (408.01)

Construction requirements for prime coats are included in 408.  An asphalt material having low viscosity is required for a prime coat.  This material is intended to penetrate a prepared granular surface prior to the placement of an asphalt concrete mixture.  The purpose is to bind the granular particles together for some depth below the surface to provide additional stability.

Asphalt Material (408.02)

One of the following types of asphalt material can be used: 702.02 MC-30, MC-70, or MC-250 or 702.03 Primer 20.  

Cover Aggregate (408.03)

Cover aggregate must conform to No. 9 size or gradation requirements of 703.05 or 703.06.

Weather Limitations (408.04)

Prime coat cannot be used on a wet surface. 

Do not apply prime coat for asphalt concrete paving or surface treatment work when the air temperature is below 50 °F or when the air temperature in the last 24 hours has been 40 °F or lower. 

Do not apply prime coat on stabilized or granular base courses when the air temperature is below 40 °F.

Equipment (408.05)

Equipment requirements for the application of tack coat are the same as detailed in 407.  These requirements include the use of tachometer, pressure gauges, and an accurate volume measuring device or a calibrated tank.  A thermometer is required to monitor temperature of the tack.  The spray system must by fully circulating and the spray bar must be adjustable both laterally and vertically.  The Contractor must provide charts or other information that shows truck and pump speeds required to obtain the application rate. 

The spreading of the cover aggregate, when required, can be accomplished by any approved method depending upon the specific job conditions.  When sweeping is required, the brooms approved for use should produce a uniform surface without causing damage.

Preparation of Surface (408.06)

The surface to be primed should meet all requirements for the particular specification item (e.g., subgrade, aggregate base, stabilized subgrade, etc.).  Irregularities in the subgrade, subbase, or base material in excess of specified tolerances must be repaired prior to priming.  These include, but are not limited to, ruts, corrugations, and high and low areas.  Mud, clumps of dirt, and other foreign material must be cleaned from the surface to be primed. 

Application of Asphalt Material (408.07)

The specified application rate for the asphalt material is an estimated rate suitable for average conditions.  Open textured surfaces may permit an increase, while dense surfaces may require a reduction in the estimated rate.  The application rate should be such that the prime will be absorbed by the material within 24 hours.

The asphalt material must be applied uniformly over the entire width of the area to be primed.  The distributor must meet the same requirements of 407.03.  If excess material is applied, the Contractor should squeegee the excess from the surface.  Any deficient or skipped areas must be coated.

Prime is shipped under ODOT’s Asphalt Materials Certification Requirements as detailed in Supplement 1032.  Weight tickets will be provided for the loads of asphalt material delivered to the project.  A weigh-back ticket must be provided to accurately determine the quantity of tack used based upon weight.  This weight will have to be converted to gallons based on the appropriate conversion factor for the tack.  Although the distributor is required to have an accurate volume measuring device, payment must be made using the weight tickets. 

Application of Cover Aggregate (408.08)

When traffic must use the primed area where the material has not penetrated completely, cover aggregate must be applied to absorb any excess material.

Method of Measurement (408.09)

Determine gallons (liters) from weight tickets or weighed partial loads (weigh-back).  For weights or volumes that are questionable or unknown, a volume-measuring device is required before accepting the material.  Cover aggregate is included in the bid price for the prime coat.

Documentation Requirements - 408 Prime Coat

1.        Measure and document air temperature.

2.        Document surface preparation (sweeping, cleaning) and condition of surface prior to the application of the prime coat.

3.        Document the temperature of material as delivered to the project.

4.        Document equipment used and conformance to specifications.

5.        Document the use of any cover aggregate.

6.        Document any issues with application (excess, deficiency) and actions taken to correct the issue.

7.        Calculate and document, for pay, number of gallons applied per 409.09, 408.10, and 109.01.

8.        Use form CA-FP-6 and other approved forms to document the tack application and calculations.

409 Sawing and Sealing Asphalt Concrete Pavement Joints

Materials (409.02)

Be sure approved materials are used per 409.02 requirements.  These include joint sealant and backer rod.

Construction Details (409.03)

Check that the following operations are proceeding properly per 409.03:

·         Saw cut the intermediate course if the surface course is not placed within 5 days.  Saw cut is 1/8 inch wide by 1/4 the depth of the intermediate course over contractor joints.  At expansion joints the saw cut is 1/2 inch wide by 1/4 the depth of the intermediate course.

·         Saw cut the surface course no later than 48 hours after paving.

·         Accurately locate saw cuts over joints with pins or stakes before paving  The Engineer shall approve the method of joint marking before any resurfacing operations begins.

·         Final saw cuts shall be 2 inches deep with a sealant reservoir that is 3/8 inch wide by 3/4 inch and is recessed 1/8 below the surface.

·         Dry cut joints shall be cleaned using compressed air by way of an air compressor with a minimum rated capacity of 100 psi.  Wet cut joints require water blast cleaning followed by drying with a propane torch or lance unit (409.03 has details on lance unit requirements).

·         The saw cut shall extend over the full pavement width including paved shoulders.

·         The joint is to be kept clean until sealing; traffic is not permitted to damage the joint before sealing.  Damaged saw cuts must be repaired prior to sealing

·         The sealer is to be heated per the manufacturer’s directions. 

·         The first gallon of material that flows out of the applicator wand at the start of the day is to be discarded and not used.

Prior to sealing, a backer rod must be placed in the clean joint and the liquid sealant immediately placed in the joint using a nozzle that is inserted into the joint and reservoir completing filling the joint.  The sealant level after cooling should be not more than 1/8 inch below the pavement surface.

Documentation Requirements - 409 Sawing and Sealing Asphalt Pavement Joints

1.        Document when the saw cuts are made with respect to paving.

2.        Review, approve, and document method for locating joints.

3.        Measure and document depth and width of saw cuts.

4.        Document joint cleaning methods, placement of backer rod, and installation of sealant.

5.        Document measurements on CA-D-2 or other approved forms.

410 Traffic Compacted Surface

Because of the simplicity this item of work, no detailed explanation of the item is required in this manual.

Documentation Requirements - 410 Traffic Compacted Surface

1.        Materials.

2.        Subgrade condition.

3.        Document location where material was used on the ticket.

4.        State if all load was used, if not, be sure to get a weigh back.

5.        Blading operation.

6.        Maintenance.

7.        Weigh tickets should be totaled with an initialed and dated tape attached. Convert to cubic yards as per 410.06 of the C&MS.

8.        Pay and measure according to 410.06 and 410.07.

9.        Document on CA-D-1 and CA-EW-12.  Do not duplicate the information on these forms unless necessary.

411 Stabilized Crushed Aggregate

Because of the simplicity this item of work, no detailed explanation of the item is required in this manual.

Documentation Requirements - 411 Stabilized Crushed Aggregate

1.        Materials.

2.        Document location of where material was placed and lift thickness.

3.        Roller weights.

4.        Lift thickness.

5.        Roller passes.

6.        Use a rubber tire roller for the final compaction.

7.        Perform the compaction tests according to S-1015.

8.        Weigh tickets should be totaled with an initialed and dated tape attached.  Convert to cubic yards as per 411.04 of the C&MS. 

9.        Pay and measure according to 411.04 and 411.05.

10.     Document on CA-D-1 and CA-EW-12.  Do not duplicate the information on these forms unless necessary.

421 Microsurfacing

Description (421.01)

This item of work is used to provide a cold laid polymer modified emulsified asphalt pavement course to fill ruts, depressions, and to provide a leveling course.  It can also be used as a surface course over existing pavements.  The mixture includes the use of crushed aggregate, mineral filler, water, polymer modified emulsified asphalt binder, and other additives. 

Materials (421.02)

Materials used in the mixture and the completed mix are approved by the Laboratory prior to beginning work.  The Contractor must provide a certificate of analysis and statement of compliance from the manufacturer with each load of binder.

Proportioning (421.03)

Verify job mix formula (JMF) approval by the Laboratory.

Weather Limitations (421.04)

The mixture cannot be placed when it is raining.

Allow microsurfacing placement if:

1.        Surface temperature is 40 °F (5 °C) or above.

2.        Air temperature within 24 hours of placement is NOT forecasted to be below 32 °F (0 °C).

3.        Surface temperature is 50 °F (10 °C) or above between September 30 and May 1.

Mixing Equipment (421.05)

Mixing equipment must conform to the specifications.  Equipment must be self-propelled, front feed, with a continuous loading conveyor system.  A gear pump must accurately proportion aggregate and asphalt emulsion. 

Mineral filler must be dropped into the aggregate before reaching the pug mill.  A spray bar must pre-wet the aggregate with water and additive before the addition of asphalt emulsion and before it drops into the pub mill.

The pug mill must be continuous flow type and a minimum of 49 inches long. 

The equipment must have driving stations on both sides.  The back mixing station must have forward speed control to allow the mixing operator to control speed and the level of mixture in the paver.

A water pressure system with spray nozzles that can spray water ahead of the spreader box may be required.

The Contractor can use truck-mounted machines with a conveyor belt delivery system on project segments of less than 15,500 square yards or use it for spot repairs.

Figure 421.A – Self-Propelled Front Feed, Continuous Loading and Mixing Machine (left) Truck-Mounted Machine (right)

Equipment Calibration (421.06)

Before mix production, calibrate the mixing equipment in the presence of the Engineer. Perform a new calibration if there is any change in the mix design. Obtain documentation of individual calibrations of each material from the equipment calibrator.  After the initial calibration, no further changes or adjustments to the mixing equipment can be made without the Engineer’s approval.

Spreading Equipment (421.07)

The spreading equipment must apply the mixture uniformly.  A standard spreader box is allowed when placing a leveling course or surface course.  For surface courses, a secondary strike-off must be attached to the spreader.

If a rut fill course is required, the Contractor must use a V-shaped rut filling spreader box equipped with a steel strike-off.

Either spreader box must be attached to the mixer and must be equipped with adjustable paddles that continuously agitate and mix the materials throughout the box.  Check for excessive buildup and settling in the spreader box and have the Contractor correct the issue.

Burlap or other drags are allowed for use to provide the desired surface finish.

Surface Preparation (421.08)

Be sure the surface is thoroughly cleaned before application.  Apply a tack coat consisting of 1 part asphalt emulsion and 3 parts water and apply at a rate of 0.06 to 0.12 gallons per square yard.  Apply tack in accordance with 407.

Remove raised pavement markers according to 621.08. Fill depressions with the same material being used for the microsurfacing.

Pavement markings and all other paint must be removed using an abrasion method.

Test Strip (421.09)

A 1,000-foot test strip must be constructed for evaluation by the Engineer.  The test must include all courses specified and must be constructed at the same time of day as the scheduled, full-scale production.  For example, if the Contractor plans night work, the test strip must also be done at night.

The Engineer will evaluate the test strip after 24 hours of traffic to determine if the mix design is acceptable.  Full-scale operations can only begin after the Engineer accepts the test strip.

If work is scheduled after May 1 and before September 30 and the Contractor has constructed a test strip with the same JMF and materials in the same construction season, the test strip may be waived. 

Application (421.10)

During application the following items should be closely checked and monitored:

1.        Uniform and complete coverage that fills cracks, potholes, and surface irregularities.

2.        No skips, lumps, or tears are allowed in the material placed.

3.        No unmixed aggregate is allowed.

4.        In a rut, fill material must fully fill ruts without excess overfilling that creates a crown of 1/8 inch after 24 hours of traffic compaction.

5.        Rut fill must be applied in 5- to 6-foot passes in each wheel path.

6.        Restore the design profile of the pavement cross-section.

7.        Leveling course must be applied at 14 ± 2 pounds per square yard (7.6 kg/m2).

8.        Surface course must be at 16 ±1 pounds per square yard (8.7 kg/m²) when placed on another microsurfacing course.

9.        Surface course must be placed at a minimum 18 pounds per square yard (9.8 kg/m²) when not placed on another microsurfacing course.

10.     Surface courses must be wide enough to cover rut fill and leveling courses.

11.     Straight lines must be maintained along curbs, shoulders, and intersections.

12.     Stop placement if excessive streaking or other problems develop.

13.     Contractor must use a rubber tire roller if the material is not exposed to traffic within 48 hours.

14.     The pneumatic roller must meet 401.13 and have a tire pressure of 40 to 60 psi (275 to 400 kPa).

15.     Squeegees are required where hand spreading and finishing is needed.

Acceptance (421.11), Method of Measurement (421.12), Payment (421.13)

Accept microsurfacing based on the Engineer’s summary of quantities for each day provided the proportion of binder to dry aggregate is maintained within 2 gallons per ton (8.5 L/metric ton). Ensure all other control requirements for proportioning and spread rate are in conformance with the specifications.

The final pavement surface must be free from excessive scratch marks, tears, rippling, streaks, and other surface discontinuities.  Longitudinal joints and transverse joints must be neat and straight.

Microsurfacing (surface and leveling course) is measured and paid by the square yards completed and accepted.  The pavement width is as shown on the plans, specified in these specifications, or as directed by the Engineer.  Length is measured along the centerline of the roadway.

Rut fill course will be measured and paid by the number of tons of dry aggregate used and accepted based on ticket weights.

The test strip will be paid based on the acceptance at the individual bid prices for each course placed.  For example, if the plans require a leveling and surface course, the test strip must be constructed using these courses and would be paid on the measured quantities for both of these items.

Tack coat is not paid separately and is considered incidental to the work.

Figure 421.B – Unacceptable Streaking (left); Unacceptable Surface Prep (right)

Figure 421.C – Unacceptable Transverse Joint and “Skip”

Figure 421.D – Uniform Coverage

Documentation Requirements - 421 Microsurfacing

1.        Check for certificate of analysis and compliance from the manufacturer of the binder and document for each load of binder.

2.        Check and document surface preparation, pavement and atmospheric temperatures, and forecast for next 24 hours.

3.        Verify and record conformance to specifications for the mixing equipment.

4.        Verify that an approved JMF is being used.

5.        Document equipment calibration.

6.        Document construction of test strip and the evaluation as well as any changes implemented.

7.        Document surface preparation and tack coat application.

8.        Document placement operation regarding uniformity, rut filling, leveling, pounds per square yard used, construction of straight lines, roller compaction (if required), issues, and corrections made.

9.        Document acceptance, method of measurement, and calculations for pay.

10.     Document on CA-D-3A or other approved forms.

422 Chip Seal

Description (422.01)

Chip seal consists of the application of polymer modified asphalt emulsion covered by an aggregate course.  It is applied as a single or double chip seal for use as a surface course on all types of pavements and on paved berms.  Chip seal can also be used as an intermediate course for a hot mix asphalt surface course.

The purpose of a chip seal is to seal and protect the underlying course from weathering and from wear by traffic.  A coating of asphalt material helps seal existing pavement cracks and joints; the cover aggregate provides a skid-resistant surface.

When applied on berms, the cover aggregate provides delineation of the traffic lanes from the berms by a change in surface color and texture.

Figure 422.A – Chip Seal Operation

Materials (422.02)

Chip seals require the use of either an emulsified binder or a polymer emulsified binder depending on the Average Daily Traffic (ADT) counts.  Only asphalt binder materials meeting the requirements of 422.07 are permitted.  Asphalt binder is shipped under ODOTs Asphalt Materials Certification Requirements as detailed in Supplement 1032.  Ensure that the material used on the project is from a certified source. 

Cover aggregate must be washed limestone or dolomite meeting 703.05.  Aggregates with a source designated as “SR” cannot be used.  The Laboratory maintains The Aggregate Source Group list that designates aggregate sources that do not provide acceptable friction characteristics and may become polished or slippery with wear.  These aggregates are designated as “SR” or “SRH.”

Cover aggregate for chip seals must be sampled and approved prior to use.  Sampling occurs at the source stockpile and at a staging stockpile location. For example, at the job site.  If there is doubt as to whether any stockpile continues to meet the required aggregate gradations, the District can sample and test at any time.

The Contractor must submit a mix design for the chip seal and receive a Job Mix Formula (JMF) from the Laboratory.

Equipment (422.03)

Distributors

The Inspector must make a general examination of the distributor to ensure compliance with the requirements of this specification and 407.03.  The equipment used for the application of a tack coat is the same as used for the application of the polymer binder for chip seal, but must include a computerized rate control that automatically adjusts the binder pump to the unit ground speed.  This control must have a gauge or meter (in gallons) that is easily read.  The spray nozzles must be appropriate for the material and rate specified.  In addition, the approval of the distributor is based on observation of the operation and check measurements of the actual application rate, performed as described in the following paragraphs. The Inspector should have the Contractor demonstrate the use of the required volume measuring device, thermometer, and application controls.  Work should not be permitted to start if this equipment is unsatisfactory.

Figure 422.B – Distributor Trucks Applying Binder

The operation of the distributor is judged by visual observation.  The quantity of material flowing from each nozzle should appear uniform.  The angle of each "fan" of material with the spray bar should appear to be the same; the angle is specified by the manufacturer.  The material should be applied uniformly across the width of the pavement, with no visible streaks and with no apparent variations in thickness, from the beginning to the end of the run.

Figure 422.C – Distributor with Improperly Aligned Nozzles (at different angles)

Streaking or ridging will not be tolerated when applying polymer binder for chip seal work.  This type of defect is generally caused by nozzles that are not all at the same angle in respect to the spray bar.  The Inspector must approve or prohibit use of a particular distributor accordingly.

Figure 422.D – Unacceptable Application of “Ridged” Binder

The results of the foregoing observations and the results of the test section are recorded for each distributor proposed for use, together with a means of identification (license plate or equipment number), and indication of approval or non-approval.  This information is entered in the project record as a supplement to the Inspector's Daily Report.

After the initial inspection, continued approved status of a given distributor depends on continued satisfactory results determined visually or by additional checks when deemed advisable.

Rollers

Only Type II pneumatic rollers conforming to 401.13 are permitted for embedding the cover aggregate; however, the maximum capacity shall not apply.

Figure 422.E – Type II Pneumatic Tire Rollers

Aggregate Spreaders

The aggregate spreader must be self-propelled with a variable width aggregate hopper (8 to 16 feet) and shall conform to specification 422.03.  The spreader must produce a uniform application of aggregate without gaps or ridges at the rate specified.  Spreaders must have pneumatic tires, a screen to prevent oversized material from passing through to the roadway, revolving cylinders, and adjustments.

Figure 422.F – Aggregate Spreader

Brooms

Rotary brooms are used for the initial surface preparation to sweep the roadway prior to the application of the polymer binder.  After the cover aggregate application, a rotary broom or sweeper is required to sweep excess aggregate from the completed surface without dislodging the embedded aggregate.  Be sure that aggregate is not being swept onto adjacent lawns.

Figure 422.G – Rotary Brooms

Weather Limitations (422.04)

For chip seals, the weather limitations are specified in 422.04.  This section requires a minimum pavement and air temperature of 60 °F (16 ºC).  Work should not begin if temperatures are forecasted to be below 50 °F (10 ºC) within 24 hours from the start of work.  Do not place the chip seal if the existing pavement temperature is 140 °F (60 °C) or above.  This work is not to be done before May 1 or after September 1.  These requirements are meant to produce quality chip seals; cool temperatures and cloudy days make application of chip seal more difficult, as is takes longer for the binder to cure out than in the heat of summer.

Test Strip (422.05)

The Contractor is required to provide a test strip to demonstrate that the equipment and operations can meet the requirements of the specifications.

The test strip must be 1000 feet long by 1 lane width wide.  The test strip must be continuous. The test strip is used to determine the binder application rate, the aggregate application rate, and the aggregate gradation. 

During the test strip, the aggregate spreader will be calibrated by applying aggregate to a piece of cardboard of a known size (generally 1 square yard).  The material is collected from the cardboard and weighed to determine the application rate (pounds/square yard).  Based on acceptance of the test strip, this will be the rate of cover aggregate application.

The proper binder application rate will be determined.  Initially the binder should be applied at the target rate specified.  The depth of embedment of the aggregate will be checked visually.  A good rate of application will provide an average of 2/3 embedment of the chip in the binder after rolling.  The Engineer will require adjustments to the rate as needed to obtain the proper embedment.  The rate will be calculated using the test strip dimensions and the number of gallons used as measured by the distributor gauge or meter (gallons/square yard).

The Engineer will review the test strip the following day.  The acceptance criteria of 422.11 will be used to determine acceptance of the test strip.  These criteria include proper chip embedment, binder streaking, ridging, flushing, loss of cover aggregate, and joint construction.  The Engineer may require another test strip if there are problems with the application.

The test strip cannot be waived and is required on every project.

Surface Preparation (422.06)

Before a chip seal is applied to an existing surface, all material accumulations, debris, foreign objects, dust, leaves, soil, etc. that would interfere with the adhesion of the asphalt material must be removed.  Proper cleaning of the surface requires power brooming and may necessitate hand scraping and power blading of heavy accumulations, such as mud.  Hand brooming may be necessary.  Special attention should be given to the edges of the roadway to ensure proper coverage of the width intended.

All existing polyester, thermoplastic, and epoxy pavement markings must be removed using an abrasion method prior to placement of the chip seal.  Acceptable removal methods include sand, shot, or water blast.  Grinding is not allowed.

For single chip seals, raised pavement markers (RPMs) must be removed or covered/protected during the chip seal operation.  Any removed RPMs must be replaced unless otherwise shown on the plans.

For double chip seals RPMs must be removed.  Removed RPMs must be replaced unless otherwise shown on the plans.

Binder Application (422.07)

A uniform application in the transverse and in the longitudinal direction is important.  Continued application should not be permitted when visible defects occur.  Where distributor results are erratic, discontinue use of the equipment until the problem is corrected.

The binder must be maintained at 150 °F to 185 °F (65 °C to 85 °C) during application and at the beginning of the day.  Binder is not to be reheated at a rate faster than 25 °F (14 °C) per hour when it has been allowed to cool to below 150 °F (65 °C).

With all other conditions being equal, the application rate of asphalt material depends on the average size of the cover aggregate particles.  In a good chip seal, the average size aggregate will be embedded for approximately 2/3 of its height after thorough seating by rolling.  This can be checked by pulling out chips by hand and visually inspecting how much of the chip is coated.  When the binder application rate is too heavy, the particles may become totally embedded, resulting in a flushed or bleeding surface.  When the application rate is too light, the particles may not be held with sufficient firmness to resist dislodging by traffic, and a loss of cover aggregate will result.

Figure 422.H – Aggregate Embedment after Rolling

The binder application rate required to produce proper embedment for a given particle size may depend upon the porosity, absorption, and firmness of the surface to be sealed.  The target rate determined by the test strip may need field adjustment depending upon the actual nature of the surface.  Considerable judgment is required to determine the proper application rate and to avoid undesirable effects of bleeding or raveling.  If proper stone embedment is not obtained, the Engineer must be notified, and the application rate adjusted and documented. 

The binder application must be started and stopped on a removable protective cover of paper, cardboard, metal or other material that protects the adjacent pavement or previous chip seal from being coated.  The use of the protective cover allows the binder to be applied at the full rate at each ending and beginning point, but does not allow the binder to be applied to existing pavement, or over applied on a previously constructed chip seal.  The binder application must not be lapped, such as where one day’s production meets the next.  The protective cover must be removed immediately after use.

Cover Aggregate Application (422.08)

Only aggregate that has been approved is permitted for use.  Collect the weight tickets when the material is received at the paving site.

The previously established spreading rate of aggregate must be verified using a 1 square yard of cardboard, weighing and determining pounds per square yard.  The Contractor must make adjustments to the spreader to meet the test section calibrated rate.

The aggregate must be sufficiently free from dust and moisture to permit immediate adhesion of the asphalt material.  Material delivered to the site with water running from the bed of the truck must be rejected.

Excessive application of cover aggregate and amounts of aggregates considered to be a nuisance to the public will require the work to be stopped.   It is unacceptable to rely on brooming or vacuuming to remove excess aggregate.  The spreading operation requires recalibration in these cases. 

Construction Operation (422.09)

General Considerations

The Contractor must establish stations for the project at 1,000 foot intervals before placing any material.  The stationing must be clearly marked and be maintained throughout the project.  Stationing is typically provided using wooden lath along the roadway and the markings should be easy to read.

The binder distributor, aggregate spreader, and rollers must be as close to each other as possible.  The binder distributor cannot be more than 150 feet ahead of the aggregate spreader.

Figure 422.I – Keep the Distributor, Spreader, and Rollers Close Together

The longitudinal joint must be placed on a lane line or as the Engineer directs.  For double chip seals, the longitudinal joint for the first course is to be placed 6 inches off the centerline, and the second course is to be placed on the centerline.

Where a double chip seal is required by the plans, the first course must be cured, swept, and capable of withstanding construction traffic.  Any deficiencies or damage must be corrected before placing the second course of chip seal.

Rolling

Rolling of the chip seal cover aggregate is required to begin immediately behind the aggregate spreader.  Three rollers minimum are required.  Do not allow the aggregate to go unrolled for more than 5 minutes.  This is to ensure that the aggregate particles will be embedded in the asphalt binder before the binder sets up.  If the binder sets before the aggregate is rolled, the result will be loose stone that must be removed.  That section of roadway would be unacceptable and would require rework. 

The specifications require a minimum of two complete roller passes of the cover aggregate.  A single complete pass is forward and back over the same area.  Each new pass must be overlapped by one-half of the roller width.  While making these passes, the speed of the roller must be slow enough, not greater than 5 miles per hour (8 km/h), to avoid displacing or dislodging the aggregate particles from the asphalt.  If stone is being picked up by the rollers, have the Contractor adjust the speed.

Sweeping and Opening to Traffic

Sweep the chip seal within 4 hours of placement of the cover aggregate using a power broom to remove loose aggregate.  The Contractor cannot reuse this aggregate in the double chip seal course.  There may be issues that do not allow the Contractor to sweep within the 4 hour timeframe, such as stone moisture, high humidity, slow binder cure rate, rain, etc.  In this case, the Engineer may suspend the operation until the problem is resolved or more favorable conditions prevail which allow for sweeping within 4 hours. 

Make sure sweeping extends 1 foot beyond the edge of the roadway to remove any loose aggregate that could migrate back to the roadway.

Before opening the road to traffic, the contractor must place “Loose Stone” and “35 MPH” signs on the same post spaced at 0.5 mile intervals.  Signs must conform to Item 614. 

Figure 422.J – “Loose Stone” Sign and Pilot Vehicle

On two-lane roads where traffic is being maintained on a chip seal, the Contractor must provide a pilot vehicle at 25 mph to guide traffic through the work zone.

The Contractor is responsible for all damage claims that result from his operations, and the chip seal surface, until the application of the final pavement markings or the application of a fog seal if required. 

Quality Control (422.10)

The Contractor is required to provide quality control of the chip seal process and must stop placement and notify the Engineer and DET if any of the parameter tolerances are exceeded.  The Contractor must identify and correct problems and receive permission from the Engineer to restart the chip seal operation.  Additionally, the Department can obtain samples at any time.  Aggregate samples can be taken from the stockpile or from the spreader to test for conformance.  If Department testing shows out of compliance material, work can be stopped.

The Contractor is to provide an asphalt binder sample on a daily basis for the Department.  The sample is to be collected within 1 hour of the start of production from the distributor truck.  The sample must be collected in a plastic container with a plastic screw lid.  After sample collection, the Contractor must give the sample to the Engineer the same day it is collected.  Additional samples may be requested by the Engineer at any time.

The binder application rate cannot exceed ±0.02 gallons per square yard from the established application rate. 

Aggregate must meet a specific moisture content and gradation as provided in 422.10.  The Contractor is required to reject material that does not meet these requirements.  If water is seen running from the truck bed when aggregate is brought to the job, it must be rejected.

The Contractor must provide a daily quality control report to the Engineer that includes the specific information as listed in 422.10.

Figure 422.K – Example of Daily Quality Control (page 1) Report by the Contractor

These items should be on the Contractor’s daily quality control report.

·         Control section, project number, county, route, and Engineer.

·         Date, air and pavement temperature, and humidity.

·         Binder temperature.

·         Beginning and ending stations.

·         Yield check on binder and aggregate (3 times per day).

·         Gradation, moisture content, and identifying station of aggregate samples.

·         Length, width, and total area chip sealed.

·         Condition of signs.

·         Contractor’s signature.

Acceptance (422.11)

Acceptance of the final product depends on daily inspection of the six items listed in 422.11 and final inspection after 25 to 35 days for the defects listed in 422.11. 

Daily Inspection and Acceptance

1.        The finished surface shall have no more than four tears or untreated areas greater than 1 inch wide and 4 inches long in any 120 square yard area.

2.        Joints are neat and uniform; there is no buildup, uncovered areas, or other unsightly appearance.

3.        Longitudinal joints have less than a 2-inch overlap.

4.        Transverse joints have no more than 1/4 inch difference in elevation as measured across the joint using a 6-foot straightedge.

5.        The edge of the chip seal does not vary more than 2 inches in any 100 feet along a shoulder or edge.

6.        Typical stone embedment is two-thirds of a typical chip.

Final Project Acceptance

Deficiencies in chip seal construction often do not show up until the surface has been under traffic for a period of time.  The Engineer and Contractor will review the completed chip seal in 25 to 35 days after placement.  Surface patterns that show streaking or ridging; bleeding/flushing; and loss of cover aggregate are to be specifically evaluated.  The Contractor is required to perform corrective work when any one defect exceeds 20 percent of any 120 square yard area.  The following are descriptions of these defects and likely causes. 

Surface Patterns (Ridges and Streaking)

Streaking is caused by faulty distributor adjustment or operation, which result in the asphalt being placed in ridges.  Contrary to popular belief, these ridges will not "flow" together, particularly when the cover aggregate is applied immediately after the application of asphalt material as required by the specifications.  Streaking results in insufficient asphalt material between the ridges to hold the aggregate in place.  This aggregate is loose and will be “kicked up” by traffic.  This leaves only the aggregate that was embedded in the ridged asphalt, thus producing a streaked appearance.

Figure 422.L – Streaking and Ridging in Completed Chip Seal

Bleeding/Flushing

Bleeding and flushing is defined as a migration of asphalt material to the surface, completely or almost completely submerging the cover aggregate.  Continuous bleeding is likely the result of too high a rate of application.  Spotty bleeding usually is the result of variations in the surface of the existing pavement.  Bleeding at tie-ins between distributor loads is the result of an overlap of the previous run.

Figure 422.M – “Bleeding” or “Flushing” of a Chip Seal

Loss of Cover Aggregate

Loss of cover aggregate is the detachment, loosening, or stripping away of the aggregate material from the asphalt binder leaving behind a black shiny surface.  This is a serious form of chip seal failure because of the traffic hazard created by the exposure to the slippery film of uncoated asphalt binder material and loose aggregate particles.  It may be caused by one or more of the following:

1.        Too light an application of the asphalt material.

2.        Penetration of the asphalt material into the underlying surface.

3.        Use of an improper grade of asphalt material for existing conditions.

4.        Delay in spreading the aggregate on the asphalt emulsion (binder has set-up).

5.        Excess aggregate application.

6.        Lack of adequate rolling.

7.        Use of wet or dirty aggregate.

8.        Opening the roadway to traffic before adequate curing has taken place.

Figure 422.N – Loss of Cover Aggregate

Method of Measurement (422.12) and Basis of Payment (422.13)

Single or double chip seals are measured by the number of square yards in place and accepted.  The actual width and length along the centerline of chip is measured for pay.

The cost of the removal of all pavement markings required according to 422.06 is incidental to the chip seal item.

Payment includes any costs to make repairs to deficient chip seals. 

Where RPMs are removed for a double chip seal, the department will pay for the removal under Item 621 Raised Pavement Markers Removed.  However, the removal of RPMs for a single chip seal is included for pay with the chip seal item.

For single chip seals, the cost of replacing of RPMs that are removed by the Contractor is included in the Chip Seal item unless the plans specifically state that they are not to be replaced.

For double chip seals, the cost of replacing RPMs should be set-up as a separate item unless the plans specifically state that they are not to be replaced.

Documentation Requirements - 422 Chip Seal with Polymer Binder

6.        Inspect and document all equipment suitability based on the specification requirements (distributor, aggregate spreader, rollers).

7.        The results of the test section must be documented, including calibration of the aggregate spreader, adjustments to binder application rate, and the Engineer’s review comments.

8.        Bills of lading for the binder and aggregate must be included in the project records.

9.        During chip seal placement, document air and pavement temperatures; binder and aggregate application operations; rolling procedure; brooming; and traffic control procedures, including all signing and use of pilot car.

10.     The Contractor must provide a Quality Control report with the information listed in section 422.10 of the specifications.

11.     Inspect and document the completed chip seal for initial and daily acceptance.

12.     Inspect and document the completed chip seal for final acceptance within 25 to 35 days after placement. 

13.     Measure and calculate for payment accepted chip seal using the actual width of placement and the length along the centerline of the roadway.  Payment is in square yards.

423 Crack Sealing, Hot Applied

Description (423.01)

This work consists of cleaning and preparing pavement cracks and placing a hot crack joint sealant.

Materials (423.02)

The hot applied crack sealer must be the type specified on the plans and meet the requirements of 423.02.  Crack sealants are known as Type I, Type II, Type III, or Type IV.

Type I crack sealant must be approved by the Laboratory before shipping to the project.  Type II and III joint sealants are mixed on the project and require the use of PG 62-22 binder and fibers.  Binder is accepted based on a certification program while the fiber manufacturer must be on the Qualified Product List.  Type II can be a premixed and prepackaged sealant.  This type of sealant requires certified test data.

Type IV sealant is a prepackaged and preapproved mixture that requires the fiber manufacturer’s representative be present during the application to ensure proper application.  The Contractor must submit a 10 pound sample of the base binder and 10 pounds of fiber to the Laboratory for approval.

Equipment (423.03)

All equipment used for crack sealing must meet the Engineer’s approval and the requirements of 108.05.

Type I sealant must be heated in a kettle or melter constructed as a double boiler.  The space between the kettle and outer shell must be filled with oil or other heat-transfer fluid.  The melter must have temperature control of the oil and have a mixing vat, mechanical agitation, and recirculation pump.  Heat cannot be applied directly to the sealant.

Type II, III, and IV sealants must be heated in a double boiler as described above for Type I sealant; there must be separate thermometers for the oil and the mix vat.  A full sweep agitator and a minimum 2-inch recirculation pump must be used in the kettle.   Heat cannot be applied directly to the sealant.

For all sealant types, a mechanical applicator wand with a flow shutoff valve is required.  Nozzles on the wand must be shaped to penetrate the crack.

Air compressors are used to clean out the cracks prior to placing the sealant.  Air compressors must be a minimum of 100 psi and have water and oil traps.

Water cleaning equipment must deliver water at 2,000 psi to the crack being cleaned.

A propane lance that produces hot air and operates at 1,000 °F, with a gas velocity of 2,000 feet per second, must be used to dry the crack.

Routing and sawing equipment must be mechanical and power driven and capable of following the path of the crack and widening the crack to a desired dimension without causing spalling or damage to the adjacent pavement.  Saw blades must be diamond and 8 inches or less in diameter.

Weather Limitations (423.04)

The pavement surface must be dry (no visible moisture of any kind) and at least 45 °F (7 °C).

Preparation (423.05)

The Engineer determines the cracks to be sealed. 

If routing is required for cracks of less than 3/4 inch wide, rout cracks to an opening 3/4 inch wide by 1 inch deep.  This is the reservoir for the joint sealant

If sawing is required, saw cracks to 3/4 to 7/8 inch wide by 7/8 to 1 inch deep.  The slivers of asphalt concrete left behind that are less than 1 inch wide along the sides of the crack must be removed.  The Contractor can use hand tools or a light weight chipping hammer. Before sealing the crack, it must be sandblasted to remove contaminants and to provide a rough face so the sealant adheres to the walls of the crack.  If the crack below the saw cut is greater than 3/8 inches, a backer rod has to be pushed into the crack to form a bottom.

All cracks must be cleaned using an approved method, including water blasting and air blasting.  All dust, dirt, debris, moisture, and vegetation must be removed from the crack.  The prepared crack must be kept clean and dry prior to sealing. 

Mixing Type II and Type III (423.06)

Determine the proper proportion of fiber and binder to blend by using weigh tickets.  Check for thorough mixing.  Check the sealant temperature against the manufacturer’s recommendation and do not let it exceed this temperature.  Be sure the temperature of Type III sealant does not exceed 295 °F (146 °C) at any time.

Application of Sealant (423.07)

Fill cracks within 250 feet (76 m) of the cleaning operation. 

Seal cracks that are wide enough to allow injection of the sealant.  Tight cracks less than 1/4 inch wide are to be sealed only if they are raveling or spalling.  Do not seal cracks greater than 1 inch wide.  Do not seal spalls and cavities greater than 4 inches wide.

For Type I and IV sealants, fill the entire crack reservoir from the bottom to about 1/16 inch above the pavement surface.  The surface must be scraped immediately with a V-shaped or U-shaped squeegee to smooth the sealant at the surface.  The band that remains on the surface after smoothing must be less than 2 inches wide.  Wider bands must be rejected. 

For Type II and Type III sealant, the width of the band should be 2 to 4 inches, but never over 4 inches.  Do not accept the work if the band is too wide and/or the thickness of the sealant on the pavement surface is more than 3/16 inches (5mm).

Opening to Traffic (423.08)

Do not allow traffic on fresh sealant until it has cured and will no long pick up and track under traffic.  The Engineer may allow the use of an anti-tracking material if traffic must use the roadway.

Method of Measurement (423.09) and Basis of Payment (423.10)

Crack sealing is measured by the number of pounds of hot applied crack sealant in place and accepted.

Documentation requirements - 423 Crack Sealing Hot Applied

1.        Document that the materials are on an approved list, have certified test data, and/or have been sampled as required.

2.        Document type of sealant used (Type I, Type II, Type III, Type IV) and mixing methods.

3.        Document the proper crack preparation procedures, including routing, sawing, and cleaning. 

4.        Document pavement conditions and air temperature.

5.        Document when the pavement is opened to traffic and any observations regarding sealant pick-up or tracking. Document and determine weight of sealant for pay.  Use weight tickets only.

424 Fine Graded Polymer Asphalt Concrete

General

This specification is intended to be used for pavement preventive maintenance, but may have other applications as well.  The specification includes two mixture compositions: Type A and Type B.  Both mixtures are required to use a polymer binder.

Composition (424.02) 

Type A material is a very fine graded mix composed primarily of natural sand and contains a very high polymer binder content (8.5 percent).  This is a recipe mix.   It is designed to give a long life, but generally is not for high truck traffic situations.  A Type A mix is normally specified as a 5/8-inch (16 mm) mat thickness.

Type B material is a fine graded mix composed of more angular materials and contains less binder content than the Type A mix (minimum of 6.4 percent).  This mix is designed by the Marshall Mix Design Method for light, medium, or heavy traffic.  The Type B mix is designed to be more rut resistant than Type A.  The Type B mix can be placed on medium and high volume roads, including most interstate applications.  A Type B mix is normally specified as a 3/4-inch to 1-inch (19 to 25 mm) mat thickness.

Figure 424.A – Item 424 (Type A and Type B) Mix Compositions

Equipment

The equipment requirements of 401 apply to this work.

Materials (424.03)

Both types of mixtures under this specification use a polymer binder.  Either a PG 76-22M asphalt binder or a PG 64-22 asphalt binder modified by the addition of 5.0 + 0.3 percent Styrene Butadiene Rubber (SBR) can be used.

The use of reclaimed asphalt pavement is not permitted in a Type A mix.

Fine aggregate for use in this specification is required to have at least 50 percent silicon dioxide by weight.  This special requirement ensures proper skid resistance for both mix types.

Coarse aggregate used in the Type B mix is required to have 10 percent two-faced crushed aggregate by weight for medium traffic applications and 100 percent two-faced crushed aggregate for heavy traffic applications.

Mixing (424.04)

When these mixtures are discharged from the plant, the mix temperature must be between 335 ºF and 370 ºF (168 ºC to 188 ºC).

Figure 424.B – Mix Texture for Type A, Item 424

Figure 424.C – Mix Texture for Type B, Item 424

Weather Limitations (424.05)

The placement of either Type A or B material cannot be placed if the exiting pavement temperature is less than 60 °F or the ambient air temperature is less than 60 ºF (16 ºC).

Spreading and Finishing (424.06)

Either mixture is to be placed and compacted per the requirements of 401; a three-wheel roller is required in the breakdown position behind the paver.  Do not use vibratory rollers when the mat thickness is less than 1-1/2 inches. 

Traffic is not allowed on the compacted surface until it has cooled enough to prevent damage.

Surface tolerances are to be checked and must be in conformance with 401.19 for transverse slope and surface smoothness.  The transverse slope cannot vary more than 3/8 inch in 10 feet.  The surface smoothness cannot vary more than 1/4 inch in 10 feet.  Ensure that the finished surface is within these tolerances as the paving progresses.

Acceptance (424.08)

Type A mixtures are to be accepted using Item 301 procedures (see Item 403) and Type II materials are to be accepted according to Item 448 procedures.

Documentation Requirements - 424 Fine Graded Polymer Asphalt Concrete

1.        State condition of base (example: primed 304, clean and dry concrete, etc.).

2.        Write location on tickets where material is placed.

3.        Mark on ticket time unloaded.

4.        Obtain temperature of the mix at project site and place this information on ticket of load checked. This should be done a minimum of four times daily or any time temperature is in question.

5.        State kind of rolling equipment and maximum tons per hour they are allowed to cover.  See example, “Roller Capacity and Placement Rate.”

6.        Calculate and document the required placement rate (Tons/Station).

7.        Document on form CA-FP-4.

8.        Lift thickness if required.

9.        Tickets should be totaled with initialed and dated tape attached.

442 Superpave Asphalt Concrete

Description (442.01)

This item is a mix design specification utilizing a gyratory compactor to produce an asphalt concrete that is used for an intermediate or surface course.  Known as Superpave, this asphalt concrete is used for higher traffic routes and can be either a 446 or 448 asphalt concrete pavement.  Superpave mix design requires the use of special equipment, material properties, and design procedures.  Superpave asphalt concrete requires inspection and documentation as per the requirements of 401 and 446 or 448.

Acceptance (442.07)

Superpave items are accepted per 448 or 446 requirements.  See those items for details.

Documentation Requirements - 442 Superpave Asphalt Concrete

1.        Obtain the approved JMF for the project.

2.        Determine and document if paver is on approved list.

3.        Document pavement surface condition, preparation, and surface and air temperatures.

4.        Document tack or prime used, along with source and quantity used, versus required.

5.        Check and document roller capacities as outlined in 401.13, if required by the specification item.

6.        Document lift thickness, mat width, weather conditions, surface tolerance checks, equipment problems, mat problems (segregation, tearing, tenderness, etc.), spreading rate, roller coverage, and any other issues or observations made during paving operations.

7.        Observe and document trucks hauling material.

a.        Check for secured waterproof cover.

b.        Check for insulated truck beds for temperatures below 50 °F (10 °C) and/or if the haul exceeds 20 miles (32 km).

c.        Observe the asphalt mix in the truck and note any slumping, drain down, or blue smoke.

8.        Determine compliance with compaction requirements as per 401.16.

9.        Record asphalt mixture temperatures in the paver hopper and on the mat at the time of compaction.

10.     Determine and record required and actual placement rates and variance.

11.     Write location (station), date, and time on asphalt plant tickets.  Tickets should be totaled daily and initialed with the calculator tape attached.

12.     Take samples, cores, or density readings as required by items 446 or 448.

13.     Record luminance readings for night paving operations.

14.     Determine plan quantity for payment.

15.     Document on CA-FP-2 through 4 or other approved forms as needed.

443 Stone Matrix Asphalt Concrete

Because of the simplicity of this item of work, no detailed explanation of the item is required in this manual.

446 Asphalt Concrete

Description (446.01)

This item includes placing a surface or intermediate course asphalt concrete that is accepted based on the level of density obtained.  The specification requires the Contractor to obtain a minimum level of density that is measured based on cores taken from the completed pavement course.  In the event the minimum required density is not obtained, there is a deduction to the Contractor’s pay for the item.  This type of specification is known as a performance specification.  Performance specifications tell the Contractor what is to be achieved, but not necessarily how to perform the work.  This differs from standard method specifications that detail exactly how the work shall be performed.  For this item, while material and equipment requirements are standard, the method of compaction is not defined; therefore, the Contractor selects the rollers for the course being placed, not ODOT.  Under this specification, a Contractor can be rewarded for providing a better product than required by the minimum specification, but as noted above, can be penalized for not meeting the minimum requirements.  The requirements of 401 apply unless noted.

Density Acceptance (446.05)

Item 446 is accepted by density testing and the roller selection is at the discretion of the Contractor and not governed by 401.13.   The requirements of 401.16 that detail compaction operations are waived except the last four paragraphs.  These last four paragraphs describe general rolling pattern requirements such as compacting the longitudinal joint first, removal of roller marks, and complete coverage.  The Inspector should observe the rolling pattern for conformance.

Density of the asphalt concrete is based on cores that are cut from the completed pavement course.  ODOT does the density testing of these cores at the District Test Lab.  Random core locations are determined by the Engineer as detailed in 446.05.  Ten, 4 inch cores are required to be cut per lot.  A lot is one day (or night) of production with provisions for combining a small production day (<400 tons) with the next day’s lot.  Each lot is divided into five equal sublots and two cores are cut from each sublot.  Core locations are determined at random by using a random number selection process.  That process will be used for all lots and is detailed below.

Core Procedure

Cores are required to be cut within 48 hours of placement.  To allow the Contractor to core the same day, determine core locations prior to the end of work by estimating production based on production rate and Contractor expectations. The Engineer should only mark the core locations for each sublot after the paving operation (including the finish roller) has completely finished rolling the sublot. The core drill operation can begin cutting cores when the newly placed pavement surface temperature is less than 140 °F. The Department does not intend to bias the Contractor’s operations by specifying where the cores will be taken.  In cases where paving is being done under a flagger closure of one lane of a two-lane highway using Standard Construction Drawing MT-97.11 or MT-97.12, some allowance can be made for allowing the paving operation to proceed concurrently with the marking and cutting of cores required for 446 density acceptance.  See, Two-Lane Flagger Closure, below for this exception.

If a cold longitudinal joint is made between the mainline and shoulder, include the shoulder area in the lot for coring.  If a hot joint is made between the mainline and shoulder, the shoulder is not included in the area to be cored, but the Contractor must use the same equipment and rolling pattern on the shoulder as on the mainline.  In this case, it is very important to monitor the rolling pattern on the shoulder.  If the Contractor does not adhere to this requirement, include the shoulder in the lot for coring.  A hot joint means the Contractor is using two pavers concurrently: one paving the mainline and one paving the adjacent shoulder.  Asphalt delivery trucks are alternated between the pavers to maintain a close distance of about one truck load of material.

There are additional, specific requirements for cold longitudinal joint cores.  In each lot, three cores are taken from the cold longitudinal joint. One core should be taken in the first and last sublots and randomly one core from one of the middle three sublots.  Joint cores are to be 3, 4, or 6 inches from the cold joint depending on its construction type.  All other cores are to be located at least 12 inches from the edge of pavement.

Form TE-217 provides a standardized method for sublot layout and random selection of core locations (transversely and longitudinally). The form is located on ODOT’s Construction website and is available as either an Excel spreadsheet that automatically calculates core sample locations or as a manual-use (non-electronic) form.

If using the Electronic TE-217 form, enter all required information as indicated by the yellow highlighting.  After entering the beginning and ending stations for the lot, press key F9 and the computer automatically generates the random numbers.  The form automatically calculates the core sample locations as shown in the orange highlighted boxes.  Use these locations to lay out the cores on the completed asphalt mat.  Note that both forms are set-up for continuous mainline paving and may have to be modified when the paving operation does not continue in a straight line.

Figure 446.A – Electronic TE-217 Form

For the Non-electronic TE-217 form, all calculations are done manually.  The selection of random numbers must come from a table.  This table is included with the non-electronic TE-217 on the ODOT website as well as instructions for selecting random numbers.  The same random number selection method should be used consistently on the project.  When this form is completed, use the calculated locations to lay out the cores on the completed asphalt mat.

The Engineer will physically mark the core locations on the mat using aerosol paint.  Be sure coring takes place where marked.  This can be ensured by observing each coring operation and by painting the core location with a small diameter circle with an “X” or other marking.  The Contractor must be instructed to cut the core within this circle.  The cut core should be examined to verify there is paint on the surface which indicates the core was cut at the selected location.  If the Contractor takes “sister” cores, make sure they are cut within 4 inches longitudinally of the Department’s cores. Sister cores are tested by the Contractor for comparison to ODOT test results.  For joint cores, use a different paint color than for the mainline cores.  This provides assurance that joint cores are cut from the locations selected by the project.

There have been isolated incidents where cut cores have been switched out with other cores that presumably would provide better density test values.  Project personnel must provide thorough oversight of the core cutting operation, so the cores being tested for payment are from the locations selected by the project through the random selection process.  Substitution of cores by cutting in other locations or by replacing cut cores with others is absolutely prohibited and will not be tolerated.

Core holes are required to be filled by the next work day using the same asphalt mixture used to place the mat.  The holes must be dry and coated with tack meeting the requirements of 707.02.  The asphalt must be compacted adequately and finished flush with the completed asphalt mat.  It is important that the core holes are dry and clean prior to tacking and filling.  Compaction must be done with a suitable tamper.  The sole of a worker’s boot is not a suitable tamper.

After core samples are obtained, package and identify in accordance with current District or Laboratory policy.  The District test lab may have specific requirements for labeling the core samples.  The samples should be shipped to the District lab as soon as possible.  Care should be taken not to damage the core by dropping, throwing, or exposing it to excessive heat.  Cores should not be stacked in any way. 

Two-Lane Flagger Closure

In cases where paving is being done under a flagger, closure of one lane of a two-lane highway using Standard Construction Drawing MT-97.11 or MT-97.12, some allowance can be made for allowing the paving operation to proceed concurrently with the marking and cutting of cores required for 446 density acceptance. 

In all cases, the Contractor should lengthen their lane closures to the maximum permissible length detailed in the above referenced Standard Construction Drawings to allow the Engineer adequate time to mark the required core locations and for core cutting operations.  The Contractor will provide to the Engineer the planned quantity that will be placed for the day’s production. 

Follow the requirements above for, “Core Procedures,” with the following changes.

Determine the planned quantity of asphalt that will be placed for that day and determine the core random locations.  The Engineer will mark the core locations after the paving operation (including the finish roller) has completely passed the selected core location. The core drill operation can begin cutting cores when the newly placed pavement surface temperature is less than 140 °F.  It is the Contractor’s responsibility to maintain the lane closure during all paving, marking, and coring operations per the requirements of the Standard Construction Drawing used for the paving operation.

Documentation Requirements - 446 Asphalt Concrete

1.        In addition to the Documentation Requirements listed in 401, use Form TE-217 to determine and record core locations for each day of production.

448 Asphalt Concrete

Description (448.01)

This item includes placing a surface or intermediate course asphalt concrete that is accepted based on plant testing and verification or plant testing and verification with field density testing.  The requirements of 401 and 441 apply to this item except as noted. 

Density (448.03)

Supplement 1055 details the requirements for performing density testing using either a nuclear gauge in the backscatter mode or an electronic density gauge, Pavement Quality Indicator (PQI) Model 300, manufactured by TransTech Systems.  Each gauge requires a specific method of operation as detailed in Appendices A and B of S1055.

Figure 448.A – PQI Electronic Density Gauge

Startup

The Contractor is required to establish a “minimum density target” during the first production day or when there are subsequent mix changes that require reestablishing the minimum density target.  The minimum density target is determined by rolling the newly placed mat until there is no change in the unit weight (pounds per cubic foot = PCF) as recorded by the test gauge.  At that time, a core is cut and tested to correlate the gauge unit weight to density.  This is done in three separate locations when using a nuclear gauge and in five separate locations when using an electronic gauge.  Readings and calculations are recorded on Form TE – Min Density Target, Nuclear, in S1055 Appendix C or Form TE – Min Density Target Elec Gauge, in S1055 Appendix D.  The cores are sent to the District Lab and tested for density.  Using the average of the gauge readings and the average of the laboratory density results, a minimum target density unit weight (PCF) is calculated that corresponds to 93 percent density.  This means the gauge reading in the field has to be at least that minimum unit weight (PCF) in order to have 93percent density of the asphalt mat. 

Example:

The following information was recorded on Form TE – Min Density Target, Nuclear.

Average of nuclear gauge readings = 142.0 PCF

Average of core density test results = 95.0%

Minimum density target for 93 percent field density = [93 x (142.0/95.0)] = 139.0 PCF (unit weight)

Therefore, in the field, the gauge has to read 139.0 PCF in order to have a minimum 93 percent mat density. 

Note: There is a time lag between when the cores are cut and tested, and the project will not know what unit weight (as recorded by the gauge) corresponds to 93percent field density.  During this period, the Contractor will calculate a required unit weight based on the JMF Maximum Theoretical Specific Gravity.  The testing technician will use this unit weight in the gauge until the lab unit weight is determined from the actual cores.

Quality Control Testing

During paving, after startup, the Contractor uses the minimum target density unit weight to maintain mat density above 93.0 percent, but less than 96.5 percent.  Quality control (QC) tests are required to be taken at 1,000 feet intervals, but the Contractor is expected to perform more than the minimum required.  Alternate the transverse location of each 1,000 foot test; start at the left side of the mat, move to the middle of the mat, then the right side of the mat, and repeat.  Tests at the edge of the mat should be taken one foot from the edge.  The Contractor will mark the test location on the pavement.

The minimum required QC tests must be recorded; interim tests do not have to be recorded.  Use Form TE – Mat Density QCQA to record the required tests.

The Contractor is expected to make changes to the rolling pattern to keep the density above 93.0 percent.

Quality Assurance Testing

The project Inspector will randomly select two locations during each production day for Quality Assurance Testing (QA).  Each test should represent one-half of the day’s production.  The first location will be at a Contractor QC test area where tests were performed that day.  The second location will be anywhere on the mat, but at least 500 feet from the start of the day’s paving.  QA tests must be located inside the closed lane.  The project Inspector must witness and initial the QA tests.

QA tests are completed using three gauge readings across the mat, left, center, and right, and averaging the density results.  The results are recorded on Form TE – Mat Density QCQA.

When one of the daily QA test density results is less than 91.0 percent, a deduction is applied to the Contractor’s payment for that half day’s production as detailed in Table 1055.04-1 in S1055.  If both daily QA test densities are below 92.0 percent, the payment deduction is based on Table 1055.04-2 in S1055 and is applied to each half day’s production.

Figure 448.B – Example of Completed QC/QA Report

Acceptance (448.05)

Acceptance of the asphalt mix is based the Contractor’s quality control testing at the asphalt plant and the District Lab Monitoring Team’s verification of the Contractor’s testing.  Sampling is typically not required at the project site, but in the event there are workmanship problems during placement, or quality control problems at the plant, the Monitoring Team may require a sample taken from the road in accordance with Supplement 1035.  If the pavement mat is less than 1-1/4 inches, the sample would be taken from the paver hopper. After a plate or hopper sample is obtained, it should be packaged and identified in accordance with current District or Laboratory policy.  The sample must be shipped to the District Lab as soon as possible or as directed by the Engineer or DET.  Samples obtained by plate sampling are tested to determine the gradation and binder content of the asphalt concrete mix. 

In addition to plant sampling and verification for acceptance, the specifications require density gauge testing according to Supplement 1055 when placing a uniform course 1 inch or thicker.  When field density testing is required, the roller selection is at the discretion of the Contractor and not governed by 401.13.  The requirements of 401.16 are waived except the last four paragraphs.  These applicable paragraphs detail the compaction operation and sequence.

Field density testing is used to determine compaction and whether a deduction to the Contractor’s pay will be made for inadequate compaction.

Refer to Supplement 1055 for the details of density testing requirements.  The Inspector should understand and monitor the testing for compliance.

Documentation Requirements - 448 Asphalt Concrete

In addition to the Documentation Requirements listed in 401, ensure forms for Minimum Target Density, Quality Control, and Quality Assurance testing are completed and submitted to the project on a daily basis. 

450 Rigid Pavement

451 Reinforced Portland Cement Concrete Pavement

General

Portland cement concrete pavement must be constructed so that it provides a smooth-riding surface satisfactory to the traveling public. It must be durable when subjected to natural weathering, traffic abrasion, and chemicals used for snow and ice control.  It must be capable of sustaining the traffic that it is intended to carry and be of sufficient skid resistance to eliminate slippery conditions when wet.

While the quality of the riding surface is the chief construction element by which the public either approves or condemns a pavement, this element is no more important than durability and structural strength.  All desirable elements of a good pavement are a product of the Contractor’s workmanship and the engineering and inspection personnel assigned to the work.

Every step of construction, from the preparation of the subgrade and base, through concrete curing and opening to traffic, has a definite effect on the rideability, durability, and structural integrity of the finished pavement. 

Description (451.01)

This item includes the construction of a Portland cement concrete pavement that contains reinforcing steel.

Materials (451.02)

Concrete

The concrete specified for use in reinforced Portland cement concrete pavement is defined in Item 499.

The coarse and fine aggregates used in the Contractor’s JMF to produce a well graded aggregate in the Class QC 1 concrete for exposed concrete pavements (Items 451 and 452) have additional requirements found in 703.02.A.  The fine aggregate used in the concrete must be natural sand; manufactured sand is not permitted.  Coarse aggregate must be provided in accordance with 703.13, in addition to the requirements of 703.02. 

Coarse Aggregate

In addition to the requirements of 703.02, the following aggregate requirements apply per 703.13.

Where gravel, crushed ACBFS, or limestone is selected, and the total combined quantity of the plan items (451, 452 or 305) is greater than 10,000 square yards (8,000 m²), the coarse aggregate must be No. 57 or 67 size. 

If the total combined quantity of the plan items (451, 452, or 305) is less than 10,000 square yards (8,000 m²), the coarse aggregate can be one of the following sizes:  No. 7, 78, 8, 57, or 67. 

Freeze-thaw resistance testing is required for all No. 57 or No. 67 gravel or limestone coarse aggregate used in 451 (or 452 or 305) to help eliminate the concrete pavement’s potential for D-cracking in accordance with ASTM C666, Procedure B.  Testing is performed by the Department.  Contact the Aggregate laboratory to validate if your coarse aggregate sources are approved.

D-cracking is cracking caused by freeze-thaw deterioration of the aggregate within the concrete.  This type of cracking can be observed in about 7 to 10 years after construction of concrete pavement.  D-cracks are closely spaced cracks parallel to transverse and longitudinal joints which multiply outward from the joints toward the center of the pavement panel.  D-cracking is a function of the pore properties of certain types of aggregate particles and the environment in which the pavement is placed.  Due to the natural accumulation of water under pavements in the base and subbase layers, the aggregate may eventually become saturated.  With freezing and thawing cycles, cracking of the concrete starts in the saturated aggregate at the bottom of the slab and progresses upward until it reaches the wearing surface.  This problem can be reduced by either selecting aggregates that perform better in freeze-thaw cycles or where marginal aggregates must be used by reducing the maximum particle size. Also, installation of effective drainage systems for carrying free water out from under the pavement may be helpful.

Figure 451.A – D-cracking in concrete pavement

Joint Sealer

Expansion joint sealer must be a 705.04 hot-applied joint sealer conforming to ASTM D 6690, Type II. 

Curing Materials 705.05, 705.06, 705.07 Type 2

These curing materials are burlap cloth, sheet-curing materials, and liquid membrane-forming compounds.  The liquid membrane-forming compounds used on the project must be on the Department’s Qualified Products List.

Tie Bar Steel, Epoxy Coated

Tie bar steel used in the longitudinal joints in concrete pavement must meet the epoxy coated reinforcing steel requirements of 709.00.

Reinforcing Steel

The reinforcing steel must comply with 709.09, 709.10, and 709.12

Dowel Bars and Basket Assemblies

Dowel bars and dowel bar assemblies (dowel baskets used to support the dowels at the proper position) must be coated with a fusion-bonded epoxy coating, which conforms to AASHTO M 254, with the exceptions listed in 709.13, Requirements for all Dowel Bars

Dowels should be inspected to ensure the epoxy coating is continuous on the lateral surface of the dowel and that the coating is not perforated, cracked, or otherwise damaged, in which case it must be rejected.  The coating must be free from holes, voids, contamination, cracks, and there shall be no more than two holes (pinholes not visually discernable) in any 12 inch (305 mm) length of the coated dowel.  The free ends of the dowels must be free of burrs or projections in addition to being completely coated.

Pavement Quality Control (451.03)

Where project pavement has a bid item ending in “with QC/QA,” the Contractor will provide a quality control plan (QCP), quality control (QC) testing, and quality control inspection.  The Engineer initially accepts the QCP.  All requirements for the QCP submittal, what is required in the Contractor’s QCP, minimum QC testing, and the Engineer’s quality assurance (QA) responsibilities are in Item 455.

Equipment (451.04)

Reinforced Portland cement concrete pavement is placed by a series of equipment called a paving train.  A paving train normally consists of a concrete spreading machine, a mesh cart, a mesh depressor, a finish paving machine, a work bridge and a cure/texture machine.

The riding qualities of a pavement depend largely on the proper operation of mechanical finishing equipment.  The equipment must be in correct adjustment.  It is almost impossible to use hand finishing to correct a poor surface left by the equipment.  Frequent checking, and minor adjustments to compensate for changing conditions, will help to eliminate surface irregularities.

The Contractor is responsible for equipment adjustments.  Department personnel are not expected to adjust or advise the Contractor on how to adjust and maintain mechanical equipment, but they are expected to observe the checking of all equipment.  The Inspector should be able to recognize when such equipment is out of adjustment or is not coordinated with the balance of the paving train.  The following information on spreaders and finishing equipment is given to provide some knowledge on the operation of the equipment.

General Equipment Requirements

The equipment used must be self-propelled spreading and finishing machines that are capable of consolidating and finishing the concrete and producing a finished surface, which meet the specified requirements.  The specifications give the Contractor the option of using slip form or fixed form pavement construction methods.

Vibrators are used for the full-width and depth of the concrete slabs to provide consolidation of the fresh concrete.  They must be internal type, using a tube or multiple spuds.  Internal means the vibrators must be immersed in the fresh concrete.  External vibration is not allowed.  Vibrators may be attached to the spreader or the finishing machine or may be mounted on a separate carriage.  They must not come in contact with the load transfer devices, subgrade, reinforcing mesh, or side forms.  Multiple spuds should not be spaced further apart than 2-1/2 feet (0.76 m).  Therefore, a minimum of 10 spuds is required for a full 24 feet (7.2 meter) width paving.

Internal vibrators must operate at a frequency of 7,000 to 11,000 impulses per minute.  The vibrators should be connected to an electronic monitoring device equipped with an automatic recorder.  The monitoring device should display the operating frequency of each internal vibrator.  The readout display should be located near the paving operator’s controls and must operate continuously when paving and display all vibrator frequencies with manual or automatic sequencing between individual vibrators.  The automatic recorder must record the following information for every 25 feet (8 m) of paving or at every 5 minute time interval.

·         The time of day.

·         Station location.

·         Paving machine track speed.

·         The frequency of each vibrator.

If the monitoring system is not equipped with an automatic recorder, the Contractor must manually record the above information every 30 minutes.  The Contractor must provide a record of the data to the Engineer each paving day.

Vibration is required for all concrete pavements.  Small, irregular areas require vibration by hand-held or machine-mounted equipment to ensure that adequate consolidation for the full-depth and width is achieved without segregation.

Vibrators must be connected so they turn off when the machine on which they are mounted stops.

Transit Mix and Mix Equipment

Concrete plants and trucks hauling concrete are inspected annually by the District Laboratories.  Concrete plants and hauling units must be checked for proper condition prior to paving operations and at regular intervals during paving.  Water and admixture metering devices will be checked to ensure proper calibration within specified tolerances.  The scales will be checked for accuracy (the specifications require that concrete materials be measured by weight).

Central mix plants should be checked to see that the mixer drum is capable of uniformly mixing and discharging the large volume of concrete.  During paving, the Contractor, or ready mix supplier, must keep mixer blades free from concrete buildup and excessive wear.

Materials should be placed in the batch plant bins by dumping into the middle of the bin with as short of a drop as possible.  Keeping the drop to a minimum reduces the chance for segregation in handling aggregate as well as in handling concrete.

Figure 451.B – Transit Mixer Truck

Even after the annual inspections, transit mixers should be checked to determine that the counters are functioning properly.  After having been mixed for no less than 70 revolutions at mixing speed, the mixer should contain concrete of uniform consistency and be able to discharge the batch without segregation.  Since this determines acceptability, mixers that do not perform in this manner should not be used and discontinued if encountered.  Sources of trouble are badly-worn mixing blades and leaky valves, which prevent mixers from producing uniform concrete.  They should not be used until corrected.

Figure 451.C – Non-Agitation Concrete Delivery Trucks

Dump-Crete Truck (left), Dump Truck (right)

When the concrete is transported to the paving site in dump trucks or other non-agitating units, check the bodies to ensure that they are water-tight and free of objectionable corners or internal ribs where concrete may accumulate.  Canvas covers that shield concrete from sun and wind shall be provided when required by the Engineer.

Aggregate Stockpiles

Contractors build aggregate stockpiles at locations where concrete will be mixed.  In all cases, aggregate stockpiles can be placed on areas which are paved, or they may be placed directly on the ground if the existing ground is firm, cleaned of foreign material, and shaped to provide drainage.   No aggregate is to be removed from the stockpile within 1 foot of the ground during production of concrete. 

Stockpiles should be built in such a manner that different types or sizes of aggregate do not become mixed, and the aggregate does not become segregated.

Coarse aggregate stockpiles must be constructed to prevent segregation.  In building the stockpiles of coarse aggregate, the Contractor is to prevent segregation through proper handling.  Methods that allow the aggregate to be deposited close to the surface of the pile helps prevent aggregate from rolling to the bottom of the stockpile and aggregate segregation.  As the pile increases in height, each layer of aggregate should be benched back to help limit rolling and segregation.

Rubber tire front-end loaders are often used to construct stockpiles.  Rubber tires must be kept clean and the bucket drops kept short.  If the front-end loader is on the pile, it should not be moved on and off the stockpile.  This can cause contamination of the stockpile. Using a bulldozer to push coarse aggregate is not permitted; this causes segregation and the use of steel treads on the pile crushes the aggregate.  Small aggregate does not segregate as easily as large aggregate because the smaller pieces are less likely to roll down the side of the pile.

Any operation which can result in segregation, degradation, or contamination is not permitted.  Aggregate stockpiles that appear segregated should be tested for gradation at the lab.

Slag aggregate and any other aggregate with a reported absorption above 3 percent must be managed in stockpiles to ensure uniform moisture content at the time of batching (499.07).  A stockpile watering system must be used that raises the aggregate moisture to saturated surface dry (SSD) or above.  The Contractor is responsible for collecting samples to confirm the aggregate moisture requirement.  Additionally, the Contractor is responsible for maintaining the aggregate stockpile at or above SSD until dewatering prior to batching in the concrete mix.  During production of concrete, the Contractor is required to test and maintain the aggregate moisture.  Variation in moisture of more than 1 percent requires more frequent testing such that the correct information is used in concrete batching.

Where QC/QA is required, the Contractor is required to test aggregate gradations conforming to Item 455.

Fixed Form Construction (451.04.A)

This construction method requires the Contractor to furnish equipment that will spread, screed, and consolidate concrete using one or more machines operating on previously placed side forms.  There must be enough equipment with capacity to perform the work at a rate equal to the concrete delivery rate.  The equipment must be self-propelled and uniformly distribute and consolidate the concrete without segregation.  Fixed form construction is used on small or irregular paving jobs because of slower productivity and potential issues with smoothness. 

The equipment must either operate on two side forms, on an adjacent lane and one side form, or on two adjacent lanes as necessary.  When operating the equipment on adjacent lanes, the adjacent lanes must be protected from damage from the equipment.

Pavers for fixed form construction must be able to spread, consolidate, and finish the concrete pavement to the cross-section and profile required using one or more machines.  The machines must be able to distribute and consolidate the fresh concrete without causing segregation.  Consolidation must be for the full-depth of the concrete thickness being placed. 

Forms for use on ODOT projects must meet the following requirements:

·         Made of steel.

·         Straight and must not be less than 10 feet (3 m) in length.

·         Have a depth equal to the pavement thickness specified.

·         Base width of at least 3-inches or greater.  Older forms will likely have a base width equal to the depth of the forms. 

·         Built-up and shimmed forms are not allowed

·         Forms that are bent or damaged are not permitted.

Figure 451.D – Sections of Steel Concrete Paving Forms (left), Forms in Place (right)

Forms must be cleaned and oiled each time they are used.  If the radius of the pavement edge is 100 feet (30 m) or less, flexible or curved forms may be used as approved by the Engineer. 

The Contractor must provide methods and devices that securely set forms and withstand paving equipment operation.  Built-up forms must not be used unless constructing less than 2,000 square yards (1,650 square meters) of pavement for the entire project.  All forms must have adequate joint locks to tightly join the ends of abutting sections together.

The surface left by the transverse screed must be uniform and satisfactory. 

Slip Form Construction (451.04.B)

This method of construction permits pavement placement without the use of fixed side forms.  In lieu of forms, a slip form paver spreads concrete uniformly across the paving area with an auger or spreader plow, consolidates the concrete with spud vibrators, and strikes off the top of the concrete and then feeds the concrete under a profile pan that provides the correct elevation and proper cross-section.  Many slip form pavers have a tamping bar that tamps larger aggregate into the top of the slab before it enters under the profile pan. When the concrete leaves the mold, the slab should retain its shape and position.  Some slip form pavers utilize an oscillating float (auto-float) or tube float after the slab is extruded.  These floats are used to smooth and seal the top of the slab; however, in some cases, they can cause the slab to be bumpy.  Excessive finishing after the slab is extruded should not be necessary if the slip form paver is set-up correctly. 

The base must be constructed as outlined in the specifications.  Stability of the base is critical for slip form construction.  The base must be graded to the plan elevation by a properly designed machine.  The track area for the paving train may be brought to grade using a form grader with a subgrader on crawlers used to grade the area under the pavement.  An automatic subgrader operating from a preset grade line is ideal for slip form construction and does not require the use of a form grader.  See Fine Grading of Subgrade or Subbase below for more details.

Stabilization in the paving machine track area in order to provide traction is permissible provided the area is scarified after pavement construction to avoid interference with lateral drainage of the subbase.  Any method of stabilization proposed by the Contractor must be approved by the Engineer.

An industry-standard, approved slip form paver must be used to spread, consolidate, screed, and finish the concrete in one pass.  The machine must consolidate the full-width and depth of pavement being placed to provide a dense homogeneous pavement slab which requires a minimum of hand finishing. 

For the placement of steel mesh, two machines may be used with the leading machine, striking off the bottom course for placement of the mesh.  The width of the bottom course may be 6 inches (150 mm) narrower than plan width, so it does not interfere with the second paving machine.

Figure 451.E – Slip Form Paving

Preset grade lines are required for slip form paving equipment to ensure acceptable riding quality of the pavement.  Paving equipment must have controls that trace the grade line and automatically adjust the screed.  String lines offset from and parallel with the edge of pavement are most often used.  Sensors on the paver follow the string line and automatically adjust the screed.

The use of string lines will not ensure riding quality.  All lines, grades, and controls should be frequently checked.  The electronic controls of a slip form paver utilizing a string line merely follow the ups and downs of the string line; thus, any dips, bumps, and errors in the string line set-up are mirrored on the surface of the new pavement.  String line should be supported at intervals that eliminate sagging of the string under its own weight.  Supports every 25 feet (8 m) produce the most desirable results.  The stringline tension must be taut enough so excessive sag does not occur.

For best results using a slip form paver, the concrete slump should be maintained at about 1-1/2 inches.  Too much slump will cause the slab edges to sag and too little slump will result in a torn or open surface.  In either case, the slab will require hand finishing to make repairs.  Good construction results are achieved by operating the slip form paver with continuous forward motion and a minimum of starting and stopping.  When the paving machine stops, all vibrating, tamping, and oscillating elements must stop.

The slip form paver must not be used like a dozer to push large quantities of concrete piles.  The Contractor is responsible for placing concrete that requires as little rehandling as possible, including pushing mounds of concrete or using hand vibrators to move concrete.  See Placing Concrete below.

Figure 451.F – Improper Concrete Placement in Front of Slip Form Paver

At the end of the day’s production, pavement at construction joints may be reduced approximately 2 inches (50 mm) in overall width.  This allows the Contractor to use an insert just inside each moving side form so that the slip form paver can be positioned at the joint when production is resumed.  The trailing side forms do not bind and spall the slab edges when this leeway is provided on each side. 

Inspection of slip form paving should include checking the pavement edges.  The pavement’s edge should be perpendicular to the pavement’s surface.  Since no forms are used to screed against or to hold the edge in place, the edge can slump downward or lean outward.  Use a straightedge placed perpendicular to the pavement’s edge to check transversely and longitudinally for slumping or leaning.  Edges must be corrected while the concrete is plastic.  The Contractor is required to make changes to the slip form paving process to prevent edge slump.

Where pavement will be placed against an outside edge, the pavement must not vary more than 1/4 inch (6 mm) below the typical section.

Where pavement will not be placed against an outside edge, the pavement must not vary more than 1/2 inch (13 mm) from the typical section.

All pavement edges must be nearly vertical with no projections or keyways exceeding 1/2 inch (13 mm).  If edge projections exceed 1/2 inch (13 mm), concrete must be removed by hand methods and the edge should be troweled smooth.

Setting Forms (451.05)

Forms serve as the “tracks” for the paving equipment, in addition to serving as forms for the concrete.  Since developments in paving equipment have provided heavier equipment, the forms play an increasingly important role in the construction of smooth pavements.

Before any forms are set on a project, they must be inspected to see that they comply with specification requirements.  They must have sufficient pin pockets for setting securely so that they will withstand the operation of the paving equipment.  Forms are to be set so they do not vary more than 1/8 inch in 10 feet (3 mm in 3 m) on the top face or more than 1/4 inch in 10 feet (6 mm in 3 m) on the vertical face.  If they cannot be reset or repaired to meet this tolerance, they cannot be used.  Forms are reused continuously.  Therefore, inspection of forms must be continuous.  Any time forms are found out of tolerance, they must be rejected.  Forms that are rejected should be marked so they are not incorporated into the work.

Figure 451.G – Forms are Set in Position and Pinned to the Base

Forms are to be set true to line and grade on a thoroughly compacted base with uniform bearing throughout their entire length and width.  Using loose earth pebbles or other shims to bring forms to the required grade is not permitted.  Whenever adequate and uniform form support is not obtained, the forms must be removed, the base corrected and compacted, and the forms reset.  At least 3 form pins are to be used in each 10 foot (3 meter) length.  These pins must be long enough to hold the form in position during the placing and finishing operations.

Figure 451.H – Built-up and Shimmed Forms are not Allowed

Pin keys must be straight and free-moving in the pockets and capable of holding the forms tight against the pins.  The joint locks must not be bent or worn and must be capable of holding the ends of the forms in true alignment.  The pins and locks are checked when the forms are set, but should be rechecked prior to placing concrete and tightened if necessary.   Make a final visual check at the same time to ensure forms are at proper line and grade.  Smooth riding pavement with good surface finish is extremely difficult to obtain with poorly aligned and set forms.

The forms are to be cleaned and oiled prior to the placing of concrete.  When hook bolts or wiggle bolts are fastened to the forms, the forms must be oiled prior to placing these units. 

Fine Grading of Subgrade or Subbase (451.06)

After the embankment has been placed and compacted, the subgrade is brought to the required grade, cross-section, and density in accordance with 203.  Base material is provided by plan for all concrete pavements with only a few exceptions.  The typical plan section indicates the depth and width of compacted base materials.  Generally, base material is 304 Aggregate Base and must be placed, shaped, and compacted in accordance with that specification.  Fine grading of the base material should be done in advance of the concrete paving operation to allow the Engineer to check the established grade for conformance to the plan elevation.  After the grade has been checked and accepted, no further disturbance of the base material is allowed.

Fixed Form Construction and Slip Form Construction (451.06.A and 4514.06.B)

For both fixed form and slip form construction, the surface of the base material is left approximately 1 inch (25 mm) above grade after compaction has been completed to the required density.  After forms have been set to grade for form paving, or the string line is set for slip form construction, the slight excess is removed with a subgrade planer (subgrader).  The fine grading operation should result in a slight removal so that the trimmed surface is compacted thoroughly without low areas.  Low areas require the addition of material, compacting, and regarding, which results in a delay in progress of fine grading.

When automatic subgraders are used, they will precede the setting of forms.  Grade will be maintained from a preset string line that will be parallel to the grade line.  After final trimming, the surface will be treated the same as for conventionally graded base.

Loose base material windrowed along the inside of the forms cannot be removed by machine, so removal of this material by use of a shovel is necessary.  This shall be done before re-compacting.

The trimmed surface left by the subgrader should be compacted to restore surface density.  This rolling operation also smooths the surface and reduces the friction between the base and the pavement.

For fine grading between forms, the resulting base surface can be checked using a multiple pin template operated on the forms or a stringline stretched between the forms.  The template must be operated behind the subgrader and roller.  Any high or low spots encountered shall be corrected immediately, then rerolled and rechecked before continuing.  Where the subgrader is operated on a string line, the grade will be checked based on the grade stakes for the pavement.  The Inspector should record the limiting stations of the area checked and conformance to the specification requirements in project records. 

The subgrader is usually one of the heaviest pieces of equipment operating on the forms.  Therefore, this is a good time for the Inspector to observe the forms for excess movement or displacement.  Areas where movement or displacement is noticed should be rechecked for compliance with requirements before placing concrete.

Moisture is controlled by spraying the base prior to fine grading, preferably in the late afternoon before fine grading.  This provides the uniform moisture distribution necessary for density.  After removal of excess material during fine grading, moisture is present for the final surface compaction.

It is good practice to recheck the alignment and grade of forms, the form locks, and the pin keys after fine grading.  Some Contractors assign employees to this job.  The Inspector should check these items regardless of the Contractor’s operation to ensure that any irregularities have been corrected.  Since the paving equipment relies on the forms for support, it cannot be expected to produce a quality-riding surface when yielding or improperly set forms are encountered.

Placing Concrete (451.07)

Prior to placing concrete, the subbase must be thoroughly moistened with water.  This keeps the subbase material from absorbing water from the plastic concrete, thus affecting its workability and decreasing its set-up time.  Different moisture levels throughout the depth of concrete can build in stresses that lead to cracking.

The concrete must be placed as close to the paving and finishing operation as possible to limit rehandling.  Excessive handling of plastic concrete can reduce the air entrainment, and therefore, the long term durability of the pavement.  

Even distribution of concrete on the base or in each course being placed is the first step toward an acceptable job. The most even distribution in initial placing results in minimum variation in final surface settlement.  If concrete is deposited in piles or windrows, unequal consolidation may take place before finishing operations are started.  This never will be overcome throughout the finishing procedure and can be the cause of unequal settlement and rough surfaces after finishing has been completed.  In the case of transmit mixer or dump truck delivery, use discharging methods that spread each batch as evenly as possible.  Better results are obtained when a hopper-type spreader is used with either transit mixer or dump truck delivery.

Concrete must be vibrated using internal vibration for the full-width and depth of the pavement being placed.  When using dowel basket assemblies, the Contractor is required to use a separate handheld internal vibrator to consolidate the concrete around the assembly.  This requirement is sometimes overlooked and must be required to ensure complete and adequate consolidation at the dowel basket assemblies.  Internal vibrators, mounted on a paver, must automatically shut off when the machine stops.  Vibrators that continue to run cause segregation of the coarse aggregate from the paste which results in weak areas in the pavement. 

Workers should not walk in the concrete unless they are wearing clean boots that do not have dirt, earth, clumps, or other foreign matter on them.  Workers should never walk on concrete that has been struck off; these boot tracks can fill with mortar which will develop as low and weak spots on the surface of the slab.

Concrete must not be allowed to displace dowel bar assemblies or expansion joints.

A separate concrete placer/spreader is required when the width of pavement being placed in one operation is 12 feet (3.6 meters) or more and the area of any given width exceeds 10,000 square yards (8,300 square meters).  When using a slip form paver with a dowel bar inserter (DBI), the placer/spreader requirement may be waived.  When a slip form paver with DBI is used, there are no dowel baskets; therefore, concrete delivery vehicles can deposit concrete directly and evenly in front of the paver. 

Placer/spreaders must be industry standard equipment that is self-propelled and receives concrete in a hopper adjacent to the area being paved and delivers the concrete using a conveyor system evenly and uniformly in front of the paver.  Placer/spreaders must be adjusted to deposit the proper amount of concrete for the required slab thickness.  The amount of concrete deposited is determined by the elevation of a strike-off plate located behind the screw augers, paddle, or hopper that distributes the concrete.

Figure 451.I – Concrete Placer/Spreaders

The elevation of the bottom of the strike-off plate in relation to the top of the forms is shown on an indicator that is visible to the operator.  The equipment should be checked to make sure that the indicator shows zero when the bottom of the strike-off is exactly even with the top of the forms.

The initial placing of the concrete should be just enough so that a slight excess is carried ahead of the placer/spreader as it levels the concrete to a uniform surface.    Unless this is done, there will be an irregular surge past the strike-off of the spreader or past the finishing screed.  This necessitates excessive manipulation of the surface in order to obtain specified smoothness requirements.  Excessive manipulation tends to alter the quality, durability, and wear resistance of the finished pavement.

Concrete should not be mixed, placed, or finished after dark without operating an adequate and approved lighting system.

When the air temperature is 35 °F (2 °C) or below, the concrete temperature must be between 50 °F and 80 °F (10 °C and 27 °C) at the point of placement.

When the air temperature is greater than 35 °F (2 °C), the concrete temperature cannot exceed 95 °F (35 °C).  When placing higher temperature, concrete setting and finishing can become an issue.  Cure and delivery time also becomes critical.  Ensure that the cure is immediately being applied and do not allow curing to lag behind the paver.  See Hot Weather Construction.

Concrete cannot be placed on any surface that is frozen or has frost.

Two test beams are to be made for each 7,500 square yards of concrete or fraction of 7,500 square yards that is placed each day.

Concrete Running Yield Check

The running yield of concrete may be determined at any time during concrete paving and can provide an easy, accurate method to ensure that the proper thickness is being placed.  When a constant width and thickness is placed, a yield factor in cubic yards per foot (cubic meters per meter) can be calculated.  This factor is determined by calculating the amount of concrete required for 1 foot length (one meter) of finished pavement of the width and depth required.  This factor is computed by using Equations 451.2 and 451.3:

Yield Factor = Width (ft) x Thickness (ft) x 1 ft

27 ft³ / yd³

Equation 451.2 – Yield Factor

Yield Factor = Width (m) x Thickness (mm) x 1 m

1000 mm / m

Equation 451.3 – Yield Factor (metric)

Running Yield = (Yield Factor) x Length Placed

Equation 451.4 - Running Yield

Example:

A Contractor is placing a 24-foot wide slab that is 9 inches thick.  Determine the yield factor and running yield for this cross-section when the Contractor placed 4,254 linear feet.  Using Equation 451.2, the following calculation results:

Yield Factor = 24 ft x (9 in/12 in/ft) x 1 ft = 0.667 yd3 per foot of length

27 ft³/yd³

Once the running yield factor has been calculated, it can be used to determine the concrete volume required for any length of slab of the same dimensions. 

For this example:  Running Yield = 0.667 yd3 per foot of length x 4,254 ft = 2,830 yd³

This is the volume of concrete that should be used for this length of pavement if it is placed to the plan width and thickness.  A comparison to the quantity of concrete used will show whether the Contractor is over or under running on yield. 

Example:

Actual quantity used = 2,880 yd³

Running yield (from above calculation) = 2,830 yd³

Over/Under run = Actual used – Running Yield = Difference

2,880 yd³ - 2,830 yd³ = + 50 yd³ difference

(50 yd³ ÷ 2,830 yd³) x 100 % = 1.77% overrun

A 1 to 3 percent greater than that required is generally due to wasting over the forms, spillage, etc.  An overrun of 3 percent or more should be investigated to determine the cause.  Overruns may be caused by several factors, including inaccurate weighing, low subgrade/base, excessive waste, line and grade, etc.  Similarly, an under run in concrete may be due to inaccurate weighing, high subgrade/base, insufficient width, thickness of slab, settlement of forms, etc. 

Hot Weather Construction

When high air temperatures, low humidity, and winds are encountered during concreting operations, the rate at which concrete hydrates (hardens) increases.  High temperatures, especially when accompanied by wind and low humidity, tend to cause a rapid loss of moisture from the surface of the plastic concrete resulting in early setting and a reduction in time allowed for finishing.

Lowering the concrete temperature to 75 ºF (24 ºC) or below will help offset the effects of high ambient temperatures.  Selection of a cool water supply is the most effective means of lowering the mix temperature.  Watering of coarse aggregate stockpiles for moisture control also aids in controlling the mix temperature.

When form paving, it is good practice to maintain the slump of  concrete near the top limit during hot weather.  Increasing the slump will help delay hydration, thereby making more time available for the finishing operations. 

During hot weather operations, there may be a tendency to add water to the surface of the concrete to aid in finishing.  This practice cannot be allowed.  Using water on the surface during finishing results in an increase in the water-cement ratio and reduces the entrained air content of the concrete at the surface.  Both of these changes adversely affect the long-term durability of the pavement’s surface.  The use of the whitewash brush to sprinkle water has caused the majority of scaling that occurs in concrete surfaces. 

Under extreme drying conditions caused by high temperatures, coupled with low humidity and high winds, mixing water may evaporate quickly from the concrete’s surface.  This water may be restored by applying a fog spray of water on the surface provided the surface has been completely finished and will not be screeded or straight edged after the fog spray.  This provision should be carefully controlled and should be the exception rather than the rule.

An approved Type B or D (705.12) set retarding admixture is required when the concrete temperature exceeds 75 °F.  Set retarders help slow down the setting time, thereby providing more time for finishing.  The use of this admixture will result in less slump loss and result in higher strength concrete. 

Protection from Rain

Concrete paving must not be undertaken in rainy conditions; however, in the course of paving, rain can occur and the Contractor must take steps to protect the plastic concrete from damage.  If the pavement is adequately protected from rain, extensive corrective work can be avoided. 

A roll of polyethylene sheeting on the finishing machine or the curing machine can be quickly unrolled to protect large areas of pavement.  When the concrete hasn’t been protected and has been damaged by rain, increased attention to corrective measures will be necessary to obtain durable concrete.

Concrete that has been exposed to rain will have some mortar or paste washed from the surface resulting in a sandy appearance along with a speckled or splattered surface pattern.  If the surface hasn’t been machine finished, it should be screeded with the machine.  This screeding will eliminate the sandy texture and force grout to the surface.  For a surface which has been machine finished, the machine may be used to make a single pass over the area affected, or the surface may be dragged with the burlap to remove the sand and work grout to the surface.  A broom drag may be used for several passes to restore the surface finish.  When correcting damage to newly placed concrete surfaces, the excess surface water must first be removed, not worked into the concrete.  Cement must not be placed on the surface in an attempt to restore cement paste washed away by the rain.  Such a practice is detrimental to the concrete and must not be allowed.

When rain persists for a lengthy period, it will be necessary to remove any protective covering to finish and texture the concrete before it sets.  Membrane curing should not be applied when the surface is wet.  If polyethylene sheeting is used as a covering, curing may be delayed indefinitely provided the sheeting is maintained in accordance with the specifications.  However, membrane curing should eventually be applied.

If rain damages the curing membrane, the surface should be re-sprayed after the excess water has dissipated to restore the impervious covering and retain moisture necessary for curing. 

If, for any reason, measures taken by the Contractor to produce a surface that meets specifications are unsuccessful, the affected portions of the pavement must be repaired or replaced to comply with contract requirements.

Cold Weather Construction

During cold weather, provisions must be made to prevent concrete from freezing until it has attained adequate strength.  Concrete that has been frozen prior to gaining sufficient strength may be permanently damaged and may never achieve the design strength.  Therefore, it is necessary to protect the concrete from freezing temperatures during the cure period.

The temperature of the concrete and the surrounding air directly control the rate of hardening of the concrete.  As the ambient temperature decreases, the rate of hardening decreases.  The rate of hardening ceases at the freezing point.  If the concrete is maintained just above freezing, it will not be damaged.  However, it will require a lengthy curing period before it will harden and gain sufficient strength.

The Contractor is responsible for protecting concrete during cold weather.  If damage might possibly occur, the surface shall be protected by any means that prevents the concrete from freezing and retains the heat of hydration.

In order to control the rate of hardening and strength gain, it may be necessary to control the temperature of the concrete being placed and to protect the concrete thereafter to retain the heat of hydration during curing.  If the air temperature is 35 ºF (2 ºC) or below when concrete is being placed, the concrete must have a temperature from 50 ºF to 80 ºF (10 ºC to 27 ºC) when placed.  The Contractor is responsible for ensuring that the concrete temperature is in the required range.

If the concrete temperature is less than 50 °F the mixing water or aggregates may be heated.  The heated water and aggregate should be introduced into the mixer before the cement so the temperature is reduced before cement is added to avoid the possibility of a flash set.  One further precaution is to delay the introduction of the air-entraining agent until the temperature has been reduced, because hot water tends to reduce its effectiveness.

The subgrade or base and forms must be free from frost when concrete is placed. Covering these areas usually prevents frost and avoids delays.

Any request to incorporate an accelerating admixture during cold weather construction must be submitted and approved.

Job Control Testing and Sampling

All material being used in the production of concrete shall be sampled, tested and approved, or accepted by certification before being used.  Material that has not been sampled before delivery to the project must be sampled and submitted for testing.  Such material must not be used until approval has been given by the Laboratory.  Sampling must be done in accordance with the specifications and as outlined in Item 499.

Concrete for use in pavements must meet the specified requirements for air, slump and yield. Tests must be conducted to check for compliance with these requirements.  The test results must be within the following limits:

AIR

SLUMP

YIELD

6 ± 2%

1 to 3 inches

± 1%

Under QC/QA, the Contractor will perform tests and report this information to the Engineer.  If random QA tests find out of tolerance concretes, the Contractor must be notified of out of specification test results and make immediate adjustments to the mix.  Production should be stopped and check tests made to confirm non-compliance of the original tests.  Concrete that does not meet specification requirements must not be used unless adjustments can be made to correct the deficiency prior to incorporating it into the work.  The fact that concrete has been produced and transported to the project does not justify its use unless it conforms to requirements.

Insufficient air may be corrected by the addition of an air-entraining agent and remixing the load to generate additional entrained air.  Variations in yield should not be cause for rejection; however, immediate adjustments must be made in the batch weights and must be followed by additional yield tests until conformance is obtained.  Slump may be increased by the addition of water provided it remains within the limits of the water-cement ratio.  If slump is excessive, the concrete should not be used.

Concrete cylinders are not required for pavement concrete.  However, if for some reason cylinders are desired, they should be cast from concrete obtained at the paving site and are to be made in accordance with Item 499.  Cylinders are to be shipped to the District Laboratory 48 hours after casting. Notify the Laboratory when the cylinders are to be tested for compressive strength (normally at 28 days of age.)

Results of air, slump, and yield tests must be recorded on the Concrete Inspector’s Daily Report and in SiteManager.  See either 499 or SiteManager help documents for required entry.  Results of flexural tests on beams are to be recorded in the project records.  Results of compression tests on cylinders (if made) will be reported by the Laboratory.

Placing Reinforcement (451.08)

Distributed steel or reinforcement used in reinforced pavement (Item 451) is welded wire fabric or mesh.  Reinforcing mesh details for pavement are shown on Standard Construction Drawing BP-1.1.  The longitudinal wire is designated as a W8.5 or D8.5 (MW55 or MD55) size and has a nominal diameter of 0.329 inch (8.4 mm).  The longitudinal wires are to be spaced at 6-inch (150 mm) centers.  A W4 or D4 (MW26 or MD26) wire is used transversely and has a nominal diameter of 0.225 inches (5.7 mm).  Transverse wires are to be spaced at 12-inch (300 mm) centers. 

The mesh holds together the slab after cracks have formed.  Adequate load transfer across the crack is ensured, and the infiltration of incompressible material into the crack is prevented or delayed.  Mesh does not increase the flexural strength of the slab.  Steel mesh is designed to withstand tensile stresses and hold the slab together.

Mesh is usually delivered to the job in advance of paving operations and stored.  It should be carefully stacked and kept clean.  Before it is used, it should be inspected to see that it has not been damaged in shipment or in storage, and that it is free from dirt, oil, and mud, which will prevent bonding with the concrete.   Any mesh that has been bent or has broken welds should be rejected.  Mesh with rust, mill scale, or a combination of both will be considered satisfactory provided the minimum dimensions are not less than specified.  Research indicates that tight, scaly, and pitted rust does not prevent bond.

Mesh should not be rejected for rusting unless the rust is so severe that the wire dimensions are reduced to less than the minimum specified.  If it is suspected that the wire dimensions have been reduced, the District laboratory should be requested to check the wire dimensions with a micrometer.

Figure 451.J – Concrete Spreader with Mesh Cart

If mesh is placed along the rough grade or the shoulder to be easily accessible during paving, it should not be done so far in advance that mud will accumulate on it.  Take care to prevent the mesh from becoming bent.

If a mesh cart is used on the forms behind a spreader, the mesh is stacked in cart-sized piles at intervals along the grade.  These stacks should be placed on wood blocks or in some manner to keep them from becoming caked with mud or soil.

The specifications allow three methods of installing reinforcing mesh. The allowable methods are:

14.     Place one layer of concrete, place the mesh on top of this layer so that it is located at its final location without any further manipulation, and place the second layer of concrete on top of the mesh. If the pavement is being placed in two layers, the concrete for the base layer should be distributed uniformly on the base and then struck off by means of a mechanical spreader to the proper depth.  The strike off should leave a plane surface without voids or high or low spots on which to place the mesh

15.     The mesh may be supported on chairs at the correct elevation and securely anchored to the base and the concrete placed in one layer.

16.     Place and spread one layer of concrete. While the concrete is still plastic, use a mesh depressor that vibrates or mechanically installs the mesh to the proper depth in the slab. This method eliminates the need for placing two courses of concrete and thereby eliminates the possibility of a plane of weakness (a cold joint) between two separately placed courses.  Control of the mesh placement within the slab is more accurate than when placed between courses, based on measurements of cores removed for checking thickness requirements.  Another advantage of this method is that a bulkhead can be placed readily and quickly in the event of breakdown since the concrete is placed full-depth and not in two separate courses.

Figure 451.K – Placing Two Layers of Concrete (left), Mesh Supported (right)

Figure 451.L – Using a Mesh Depressor

Mesh is required to be located in the slab within the range of 2-1/2 inches to T/3 + 1 inch (64 mm to T/3 + 25 mm) below the finished concrete surface (where T is the thickness of the pavement).  In its final position, reinforcing mesh must not touch either dowel bars or tie bars.  Mesh must also be located so there is 2 inches (50 mm) clearance from a longitudinal joint or pavement edge to the reinforcing wires and 12 ± 2 inches (300 ± 50 mm) from any transverse joint.

Figure 451.M – Location of Mesh in the Slab

If the mesh is bent, it should be straightened before it is placed. If it has a gradual bow, place it so the concave side is down.  Workers placing steel must not track mud or dirt into the concrete.

Two types of machines have been approved to vibrate the mesh into position.  One type consists of a grid of steel plates approximately 15 feet (4.6 m) in length and extending the full-width of pavement being placed.  The self-propelled machine is positioned over the mesh, stopped, the mesh depressed into the freshly placed concrete, and moved ahead to repeat the operation.

The other type is self-propelled and consists of long tapered longitudinal runners across the width being placed.  This machine gradually depresses the mesh into position in the fresh concrete using an oscillating tamping motion while continuously moving forward.

Since there is forward movement during placing, the latter type of machine may cause movement of the mesh across transverse contraction joints when not properly adjusted.  When using a machine of this type, periodic checks must be made by uncovering the mesh at joint assemblies to ensure that the specified clearance of 12 ± 2 inches (305 ± 51 mm) is being maintained on each side of the center of the transverse joint.  If the mesh position is found to be out of tolerance, it should be corrected and the machine adjusted at once or its use immediately discontinued.  Production may be continued without the mesh installer by changing to the two-course method.

Both types of machines can be adjusted to control the depth of the mesh.  Therefore, depth checks must be made daily to confirm that the machine is placing mesh to the required depth.  Standard when mesh depth is out of tolerance, immediate adjustments must be made by the Contractor.

Reinforcing mesh is normally shipped in lengths of 19 feet (5.9 m) by 11 feet 8 inches (3.6 m) wide which will fit the specified joint spacing of 21 feet (6.5 m) for reinforced concrete pavement with an allowance of 12 ± 2 inches (300 ± 50 mm) from the center of each transverse joint.  If shorter lengths are provided, transverse laps must be 12 inches (305 mm) and mesh sheets must be fastened at the edge of the lane and two other locations.

Usually mesh is not fabricated for lane widths greater than 12 feet (3.6 m).  Therefore, when placing pavement lanes in excess of 12 feet (3.6 m) in width, it will be necessary to tie additional mesh to the standard width sheet.  This is done by tying the outer longitudinal wire of adjacent sheets together.  A minimum of four ties should be placed along the overlapped longitudinal wires to hold the two sections of mesh in the same plane until the concrete sets.

If the screeding operation has been done properly and the mesh placed in flat sheets and tied properly, there will be no difficulty with the steel working up into the finishing operations.

Joints (451.09)

Joints are classified as transverse and longitudinal.  Transverse joints are further classified as contraction, expansion, and construction joints.  Detailed instructions for joints are found in the specifications and in the standard construction drawings.  See Standard Construction Drawing BP-2.1 for longitudinal joint details and BP-2.2 for transverse joint details.  The Inspector should know the requirements of the specifications and the drawings before inspecting joint construction. 

All transverse joints are to be constructed normal (perpendicular) to the centerline of the pavement lane unless otherwise noted on the construction plans and are to be coated with a thin, uniform coat of new light form oil.  Only new oil should be used.  The oil coating should be applied no sooner than 2 hours prior to concrete placement.  For example, it is not acceptable for the Contractor to oil the dowels the day before the concrete is placed.  For slip form construction which uses mechanical dowel bar inserter, the dowels must be oiled just prior to loading the dowels into the machine.

Joint sawing is required to prevent uncontrolled cracking of concrete pavement and is required for all transverse contraction joints. Joint sawing is also required for all longitudinal joints when concrete pavement has been placed across two or more lanes at the same time. 

The timing of the sawing operation is critical.  The use of HIPERPAV software is required to determine the sawing time limits to help protect from early, uncontrolled cracking.  The software is available as detailed in Supplement 1033 as well as the requirements for analysis.  Note: the use of HIPERPAV does not relieve the Contractor of his responsibilities under 451.17 regarding the repair of cracks in the completed pavement.

The HIPERPAV analyses must be run 24 hours prior to placing concrete and for every pour.  The HIPERPAV files and printout must be provided to the Engineer.  If HIPERPAV predicts early age slab cracking will occur, whether due to standard construction practices, joint sawing methods, mix design or curing, the Contractor cannot start construction until modifications have been made to eliminate HIPERPAVs predicted slab cracking. 

If HIPERPAV predicts that joint sawing can exceed 24 hours, all joints must be cut by the twenty-fourth hour.

Sawing must be done after the concrete has sufficiently hardened and is able to support the sawing equipment and to avoid spalling and raveling.  This operation cannot be tied to normal working shifts.  A standby saw is required at the paving site in the event of the breakdown or inability of one machine to maintain necessary progress.

Inspection should include random checking of each day’s sawing to ensure the width and depth specified is achieved.  Saw blades will wear with use, so continued checks must be made.  Since the timing of sawing is critical, inspectors assigned to this operation must be aware of the importance and document the actual time of sawing. 

Sawing may be done wet or dry and the cut must be cleaned by a jet of water (if sawed wet) or air under pressure (if sawed dry).

Longitudinal Joints (451.09.A)

Joints between adjoining lanes of pavement or shoulders are longitudinal joints.  They are necessary to control cracking in the longitudinal direction due to the warping stresses in wide concrete slabs.  Joints between separately placed adjoining lanes are longitudinal joints, as well as construction joints, and are often called longitudinal butt joints.  Most pavement lanes are 12 feet wide.

Epoxy coated tiebars or hook bolts are required at longitudinal joints to tie the lanes and prevent them from moving apart or from settling unevenly.  Since they tie the lanes together by bond, tiebars or hook bolts are not to be oiled.

Longitudinal Joint - (in Simultaneously Placed Lanes)

Both tiebars and hook bolts should be placed in accordance with the requirements of standard construction drawings called out in the plans.  Tiebars are 5/8 inch (16 mm) in diameter, deformed reinforcing bars, 30 inches (760 mm) in length.  The spacing of tiebars or hook bolts varies with the pavement thickness.  The maximum spacing of tiebars is 26 inches for pavement that is 10 inches (250 mm) thick or less and 20 inches (508 mm) for pavement that is greater than 10 inches (250 mm) in thickness.  Tiebars or hook bolts must be placed approximately at right angles and placed at one-half the thickness of the pavement.  For example, if the slab is 10 inches thick, the tiebars are to be placed at 5 inches as measured from the surface of the slab.

Tiebars may be set on chairs prior to concrete placement or inserted in the plastic concrete using a mechanical device on a slip form paver.  Chaired tiebars must be adequately anchored to the base material.  A mechanical inserter must be able to install the tiebars at mid-depth in the plastic concrete.  Tiebars must be inserted after the concrete has been placed to its full-depth and after the reinforcing mesh is placed (mesh is not required for 452 or 305 pavement).  Pushing tiebars into the plastic concrete by hand is not acceptable.

Figure 451.N – Mechanical Tie Bar Inserters

Center Tie Bar (left), Edge Tie Bar (right)

Figure 451.O – Tie Bars can be Supported prior to Concrete Placement

When a standard (water-cooled diamond bladed) concrete saw is used to make the longitudinal joint between simultaneously placed lanes, the following applies:

·         Pavement ≤ 10 inches thick: Saw the joint to a minimum depth of one-fourth the specified pavement thickness.

·         Pavements > 10 inches (255 mm) thick: Saw the joint to a minimum depth of one-third the specified pavement thickness.

·         Saw joints 1/4 ± 1/16 inch (6 ± 1.6 mm) wide as measured at the time of sawing.

When using early-entry (dry cut, light weight) saws, only use saw blades and skid plates as recommended by the manufacturer. Perform the early entry sawing after initial set and before final set as follows:

·         Saw the joint 2-1/4 to 2-1/2 inches (56 to 63 mm) deep.

·         Saw joints approximately 1/8 inch (3 mm) wide as measured at the time of sawing.

Longitudinal Joint - (between Separately Placed Lanes)

Standard, 30-inch long tiebars can be installed in the slip formed edge of the pavement using a mechanical inserter at longitudinal joints when lanes are placed separately.  This is normally done by a mechanical ram which pushes a tiebar 15 inches into the edge of the slab along the joint and at the center of the slab.  Tiebars cannot be placed by hand.  Bent tiebars are not permitted in longitudinal construction joints.

Figure 451.P – Mechanically Inserted Tie Bars with Slip Form Paver (Left), Hook Bolts Used With Forms (right)

(Note that spec now requires epoxy coated hook bolts)

The epoxy coated hook bolt or an epoxy coated hook bolt alternate (wiggle bolt) may be used in longitudinal joints when using fixed form paving.  An epoxy coated coupling attached to one-half of the device is bolted to the side-form for the first lane placed.  Before placing concrete in the adjoining lane, the other half is coupled to the embedded part after removal of the forms.  The hook bolts are to be securely fastened to the forms so they are positioned properly in the slab.  The right-angled hooks on each side of the coupling anchor provide the tie.  The position of the hooks is not important, that is, they do not have to be turned down, up, or sideways.

The inside and outside edges of the paved lane must be edged to a 1/8-inch (3 mm) radius.  The slab should be edged as soon as the concrete becomes stiff enough to remain firm without running back into the groove.  The edge should be cut first with a small trowel and then followed by the edger.  The edging tool should be held flat with the pavement surface.  Tool marks left by the edging tool must be removed.  Since the final texturing is to follow edging, this operation must not be permitted to lag.

Figure 451.Q – Radius Edger and Removal of Tooling Marks

Longitudinal joints (butt joints) between separately placed lanes require extra care to ensure that a smooth transition from one lane to the other will result.  Good workmanship is necessary at these joints to obtain satisfactory results.  Hand finishing and straight edging should be performed carefully so that each lane will be at the same elevation.  The surface of the pavement in the joint area should not vary more than 1/8 inch (3 mm) from a 10 foot (3.0 meter) straightedge in both longitudinal and transverse directions.

Figure 451.R – Edging and Finishing a Longitudinal Butt Joint

Transverse Joints

Transverse joints include contraction joints, expansion joints, or expansion joints.  All transverse joints are constructed normal (perpendicular) to the centerline of the pavement lane unless otherwise shown on the plans.  All transverse joints require the use of smooth, epoxy coated, round dowels.  The size of dowels is dependent on the thickness of the pavement as shown in Table 451.09-1 in the specifications.

Table 451.09-1 Dowel Size

Thickness of Pavement (T)

Diameter of Steel Dowels

Less than 8-1/2 inches (215 mm)

1 inch (25 mm)

8-1/2 to 10 inches (215 to 255 mm)

1-1/4 inches (32 mm)

Over 10 inches (255 mm)

1-1/2 inches (38 mm) or as in the plans

Load Transfer Devices (451.09.B)

Dowels can be placed in concrete pavement using dowel basket assemblies.  Dowel basket assembly wires, as well as the dowels, are required to be epoxy coated according to 709.13 of the Specifications.  Dowel basket assemblies shall conform to Standard Construction Drawing BP-2.2. 

Dowel basket assemblies are not to exceed the maximum spacing for the type of pavement specified (reinforced or non-reinforced) and must be perpendicular to the centerline and edge of proposed pavement or forms.  Locating the transverse alignment may be by any method that ensures a right angle to the centerline.  On curves, the joints should be approximately on radial lines.

Transverse contraction joints must be continuous across the full-width of pavement placed.  Therefore, the joint in a lane already placed must be continued across all other adjoining lanes.

Figure 451.S – Dowel Baskets are Pinned to the Base Material

When properly located and placed, dowel basket assemblies are anchored in place with steel pins.  At least eight 1/1/2-inch (13 mm) diameter steel pins, 18 inches (460 mm) in length, are required to hold each 12-foot (3.6 m) basket assembly.  The pins are driven at an angle to brace the assembly from lateral movement and to prevent vertical displacement when concrete is placed.  Two of the pins are driven opposite each other at each end of the dowel assembly and the remaining four are driven in a staggered pattern on each side.  The assembly should not be hit when driving the anchor pins.  If wires of the basket are bent, the dowels may be thrown out of line and require the entire assembly to be rejected unless it can be removed, straightened, and reset properly.  Any badly distorted assembly should be rejected.  The epoxy coating must not be damaged during the any operation.

If concrete pavement is placed on an existing concrete pavement or stabilized base, the dowel baskets must be held firmly in position by use of power-driven fasteners and appropriate clips or pins driven in predrilled holes of a diameter slightly less than the pin diameter.  The Contractor may use either of these methods or a combination of the two in sufficient numbers to adequately anchor the basket assembly.  The method used must secure the dowel basket from lateral and vertical displacement during concrete placement.

While the specification allows the use of steel bearing plates when placing basket assemblies on granular material that may distort, this practice is not common and should not be used for standard construction purposes.  If there is a base stability problem this must be corrected before pinning basket assemblies.

Shimming of basket assemblies with pebbles, stones, wood, etc. is not permitted.  If shimming is necessary, it is obvious either that the base is not prepared properly or the dowel basket assembly is bent or misaligned.  In either instance, the base or assembly must be rejected until corrective action has been completed.

Dowel Shipping and Spacer Wires

After dowel assemblies have been set and anchored properly, the shipping and spacer wires used to hold both halves of the dowel basket together during shipping and handling must be removed.  The shipping wire is normally cut at two locations and removed immediately prior to placing the concrete.  The shipping and spacer wires are usually a small diameter wire parallel to the dowels and hooked or tack welded to the basket assembly wire.  Shipping wires run the same direction as the dowels.  Dowel basket assemblies must be anchored to the base before the shipping and spacer wires are removed.

Figure 451.T – Shipping Wires Fully Removed (left) and Only Cut (right)

Checking Dowel Basket Assemblies

Specifications require that dowel basket assemblies be preset prior to the beginning of paving unless the Engineer determines that it is impractical to do so.  This allows time to check the baskets to ensure they are parallel to the base and centerline of the pavement.  Checking of the assemblies is to be done after the removal of the shipping and spacer wires.  Measurement checks of the distance between the dowel and the forms (made at each end of the dowel) or the proposed edge of pavement provide a check for being parallel to centerline.  The distance to each end of the dowel must be equal for the dowel to be parallel to the forms and the centerline.  After some experience, this check can be visual when fixed form paving since dowels out of alignment are easy to spot in relation to the forms.

Figure 451.U – Checking Dowel Level with an A-Frame Level

An adjustable A-frame level is used to check several dowels in every assembly unit to ensure that all dowels are parallel with the surface of the base.  The level is first placed on the base adjacent to a basket assembly and adjusted to read level.  The level is then placed on the dowels.  The bubble will indicate level if the dowel assembly is set properly and is parallel to the surface of the base.  Check as many dowels as possible, but at least three dowels should be checked in each 12-foot (3.6 m) section, , one at each end and in the middle.  If the dowels are not parallel with the surface when checked, the assembly must be adjusted and rechecked.  If proper alignment cannot be obtained, the assembly must be removed and replaced.

Slip Form Paving using a Mechanical Dowel Bar Inserter (DBI)

The Contractor may propose to use a slip form paver with a mechanical device that automatically inserts dowels in the plastic concrete during the paving operation.  Dowels placed using a DBI must be placed in the full thickness of the concrete pavement slab.  A DBI is integral to a slip form paver and is located behind the vibrators and the initial strike-off of the paver.   The DBI consists of a rack located above the slab and in the correct transverse locations across the slab.  The loose dowels are loaded into the rack, and the dowels drop into place and are pushed into the fresh concrete using metal forks that push (and sometimes vibrate) the dowel to the correct elevation in the slab. The metal forks must insert each dowel so that it is parallel to the base and the pavement centerline and be at the center of the slab thickness.  After the dowels are placed at mid-depth, the forks are withdrawn leaving the dowels in position and supported by the concrete.  The dowels are to be installed after the concrete is placed to its full depth, and if required, after the mesh is positioned properly.  The only operations permitted after positioning the dowels are the machine’s final strike-off, mechanical float finishing, and hand finishing the concrete’s surface.

The specifications require the Contractor to submit to the Engineer details and specifications of the proposed slip form paver with DBI at least 14 calendar days prior to bringing the equipment to the project.  The use of the slip form paver with DBI must be demonstrated using a test section and specialized scanning equipment to verify the location of dowels in the completed pavement.

Verification of dowel placement is done using MIT Scan-2 equipment and software.  The MIT Scan-2 uses magnetic tomography to locate the dowels in three dimensions.  The equipment provides an immediate print out in the field and a detailed report of each dowel in the joint including all measurements and a color depiction of the dowels in the joint.

Figure 451.V – Checking Dowel Alignment Using a MIT Scan-2 after Placement with DBI

Dowels placed using a slip form paver with DBI have a required placement tolerance as shown in the Table 451.09-2. Note: dowel basket assemblies have tolerances as shown on Standard Construction Drawing BP-2.1.  These are the manufacturing tolerances for the basket and dowels in the basket.  As noted above, the dowel basket assemblies require checking for level and perpendicular placement with the joint.

Dowel misalignment can result in poor load transfer and joint locking which is detrimental to the performance of the pavement. 451.09-2 states the allowable tolerances for each of the following misalignment parameters:

Table 451.09-2

Individual Dowel Bar Alignment Tolerances

Alignment Parameter

Acceptance Tolerance (inches)

Rejection Criteria (inches)

Horizontal Translation a

±2.0

±3.0

Longitudinal Translation b

±2.0

±4.0

Vertical Translation c

±1.0

± T/6

Horizontal Skew d

±0.60

±1.0

Vertical Tilt e

±0.60

±1.0

Cover f

-

2.5 minimum

a.           Horizontal Translation - the total difference, measured horizontally, between the actual dowel bar location and the plan required dowel bar location along the transverse contraction joint.

b.          Longitudinal Translation - the total difference, measured in the longitudinal direction, from the center of the transverse contraction joint to the actual dowel bar center. Also termed as “side shift”.

c.           Vertical Translation - the total difference, measured vertically, between the centerline of the actual dowel bar location and the mid-depth of the slab. (T = Pavement Thickness in inches)

d.          Horizontal Skew - the total difference, measured from end to end of a dowel bar, of the dowel in the horizontal plane.

e.           Vertical Tilt - the total difference, measured from end to end of a dowel bar, of the dowel bar in the vertical plane.

f.           Cover - the least distance between the surface of embedded reinforcement and the outer surface of the concrete.

Rotational misalignments (horizontal skew and vertical tilt) must be evaluated using a Joint Score Analysis per an FHWA publication called Best Practices for Dowel Placement Tolerances (CPTP Tech Brief, FHWA-HIF-07-021).  The Joint Score is a measure of the combined effects of rotational misalignment. 

The Joint Score (JS) is calculated using a weighting system that assigns a number to each dowel bar in a joint depending on the amount of deviation.  The deviation is referred to as Single Dowel Misalignment (SDM), and is the resultant misalignment of a dowel. SDM is calculated as the square root of the sum of squares of horizontal skew and vertical tilt. 

Horizontal and vertical misalignments are the skew and tilt measurements determined using the MIT Scan 2.  Once the SDM is calculated for each dowel in the joint; determine the weighing factor (W) for each bar from Table 451.09-3; sum the W values for every dowel in the joint and add one (1) to calculate the Joint Score (JS).

 Table 451.09-3

Weighting Factors in Joint Score (JS) Determination

Single Dowel Misalignment (SDM)

W, Weighting Factor

SDM ≤ 0.6 in. (15 mm)

0

0.6 in. (15 mm) < SDM ≤ 0.8 in. (20 mm)

2

0.8 in. (20 mm) < SDM ≤ 1 in. (25 mm)

4

1 in. (25 mm) < SDM ≤ 1.5 in. (38 mm)

5

1.5 in. (38 mm) < SDM

10

Joint Score (JS) – Evaluated for a single transverse joint between adjacent longitudinal joint(s) and/or pavement edge(s) (i.e., a typical 12 ft [3.6 m] standard lane or up to 14 ft [4.3 m] widened lane), and calculated as:

where:

n =       number of dowels in the single joint

Wi =     weighting factor (Table 451.09-3) for dowel i

The Joint Score threshold for a locked joint of 10 (JS=10), was developed for a nominal pavement width of 12ft and must be adjusted to account for differing pavement widths. This adjustment is made using the Joint Score Trigger (JST).

Joint Score Trigger (JST) – A scaling of the Joint Score risk value to account for the actual number of dowels required in a single joint for pavement width other than 12 ft (3.6 m), calculated as:

Include the Joint Score and Joint Score Trigger for every joint scanned in the report to the Engineer.  Any joint with a Joint Score equal to or greater than the Joint Score Trigger is considered locked and rejectable.

Joint Score Example

·         Excel spreadsheet from MIT Scan-2 software for Joint No. 24

·         Horizontal and vertical misalignments shown on the spreadsheet as “sh” and “sv.”

·         Calculate the resultant misalignment (deviation) as the square root of the squares of horizontal and vertical misalignments.

·         Assign a weight for each dowel based on the resultant misalignment.

·         Multiply the number of bars in each weight category times the weight.

·         Total products of number of bars x weight and add 1.

·         In this example, the Joint Score = 14.

In this example the joint being measured is 24 feet wide so the number of dowels required is 24. The JST should then be calculated as follows:

We now check to ensure that the JS < JST and (14 < 20) so the joint has an acceptable joint score. Keep in mind that the JS is not the only a measure for a compliant joint. All other parameters of Table 451.09-2 must be met as well.

Test Section

Prior to using a slip form paver with DBI on a project, the Contractor is required to perform a test section of at least 500 feet.  Every joint in the test section must be verified for accuracy of dowel bar placement using the MIT Scan-2 equipment.  The slip form paver and DBI can be accepted for production paving if the following acceptance criteria are met:

1.        Each Joint Score (JS) is less than Joint Score Trigger (JST);

2.        Ninety percent (90%) of the dowel bars meet the Acceptance Tolerances of Table 451.09-2;

3.        None of the dowels exceed the Rejection Tolerances of 451.09-2.

When the test strip does not pass the stated requirements, the Contractor must make adjustments to the paver, mix or other parameters and retest.  In some cases, the Contractor may have to remove and replace the test section pavement.

New test strips are required at the beginning of every construction season, after any major paver repair or maintenance, at every mobilization and remobilization to a project, and after any major concrete mix design change.  A paver that is approved for use on one project must still pass the test section requirement on every other project it is used on.

Any ferrous metal, namely tie bars, that is too close to the dowels being measured can reduce the accuracy of the MIT Scan-2 device. Determine during the test section if embedded tiebars or other project conditions are affecting the Rejection Tolerances and JS’s.  If the test section demonstration shows interference, exclude from the JS and JST calculations any dowel bar(s) closer than 12 in. (300 mm) in any direction to tiebars in the longitudinal joint(s).  At the Engineer’s discretion, establish the location of excluded dowels by another equivalent non-destructive method or by probing.

Production Paving

After completion and acceptance of the test section, the Contractor can begin using the approved slip form paver and DBI.  During production paving, the Contractor is required to scan every 10th joint. The Engineer can request additional scans be performed if needed.

The Contractor is required to provide a report of the scanning within 24 hours of each day’s production.  The report shall include the Joint Score as well as the Excel files and graphical output for each joint.  The report should include a summary where the results from each scanned joint are presented and easily reviewed.  An initial report can be used by the Engineer to determine whether paving can continue.

The Engineer will base the decision to keep paving as described below:

1.        When the daily Quality Control Testing (QCT) finds more than 10 percent of the joints scanned have dowels exceeding the acceptance tolerances of Table 451.09-2 but the JS is less than the JST, increase the scanning frequency to every 5th joint.  Evaluate the paving process to reduce/eliminate misalignments and mislocations and continue to pave.  The QCT frequency will revert back to every 10th joint when two consecutive days of scanning every 5th joint show no dowels exceeding the acceptance tolerances of Table 451.09-2 and all JSs are less than the JST.

2.        When QCT finds any individual dowel bars exceeding the rejection criteria of Table 451.09-2 or the JS is found to exceed the JST, the joint is considered to be locked and immediate investigation needs to be made as follows: 

a)        Scan joints in front and behind the locked joint location until five (5) consecutive joints in both directions are found with no dowel bars exceeding the rejection criteria of Table 451.09-2 and no JS is found to exceed the JST.

b)       If the additional scanned joints show no additional dowel bars exceeding the rejection criteria of Table 451.09-2 and no JS exceeding the JST, evaluate equipment to determine what caused the original problem.  Before continuing paving increase the frequency of QCT to conform every 5th joint.

c)        If the additional scanned joints show additional dowel bars exceeding rejection criteria of Table 451.09-2 or joints with a JS exceeding the JST, stop paving.  Investigate to determine the cause of the dowel bar rejection issues and provide the causes and alternative corrections to the Engineer.

The Engineer will determine if the corrections will correct the problem and may allow paving to temporarily continue to validate if the corrections work.  During any evaluation, scan all joints to determine if the corrections were successful.  If successful, continue QCT scanning at the frequency of every 5th joint.  If not successful, discontinue paving, repair or replace the slip form paver and DBI, and repeat the Test Section

All dowel bars found beyond rejection criteria of Table 451.09-2 or joints with a JS exceeding the JST require a corrective action proposal conforming to 451.09.B.5, Corrective Action.

Corrective Action

The contractor must submit a proposal for corrective action to the Engineer for any dowel that exceeds the rejection criteria in Table 451.09-2 or any joint that has a JS greater than the JST. The Engineer should evaluate the proposal and approve of any corrective actions prior to them being performed by the contractor. 

Corrective action for all JS exceeding the JST may not be required, if they are random in nature. Up to two (2) consecutive joints with a JS exceeding the JST may be accepted, provided that the adjacent three (3) joints before or after do not have dowels exceeding Table 451.09-2 rejection limits and have JS’s less than the JST. Corrective action is required where there are more than two (2) consecutive joints with a JS exceeding the JST.

Expansion Joints (451.09.C)

Relief for compressive forces that are caused by movement in the pavement (typically in hot weather) is provided at bridges, structures, and intersections in the form of expansion joints.  Expansion joints permit contraction and expansion of the concrete pavement. 

The first two regularly spaced joints in the concrete pavement adjacent to a bridge approach slab must be expansion joints (when a pressure relief joint is not included in the plans).  Other expansion joints may be detailed in the plans at locations at other structures and intersections.  Standard Construction Drawing, BP-2.2 provides additional information on the installation of expansion joints.  All expansion joints are doweled and allow the pavement to expand or grow due to temperature variations.  A standard expansion joint allows for 1 inch (25 mm) of expansion.

Figure 451.W – Typical Expansion Joint (left), SCD BP-2.2 Detail of Expansion Joint Section

If the pavement consists of two or more separately placed lanes, the expansion joints must be a continuous straight line for the full-width of the concrete pavement, including concrete shoulders.  All expansion joints are perpendicular to the centerline adjacent to a skewed approach slab.

Preformed compressible material, 1 inch (25 mm) thick, is installed in the dowel assembly at the location of the expansion joint.  It must be set perpendicular to the dowel as well as perpendicular to the line of forms and the pavement centerline.  The material must extend down to the base and to the side forms to allow free movement throughout the entire joint.  The top of the expansion material is held 1 inch (25 mm) below the pavement surface.  It is permissible to place the expansion material closer to the pavement surface to facilitate sawing of this joint, provided all material is removed to a depth of 1 inch (25 mm). The 1 inch by 1 inch area at the top of the expansion joint shall be sealed using a hot applied joint sealer which meet the requirements of 705.04.

Standard 18 inch (460 mm) long epoxy coated dowels are required for load transfer in all expansion joints.

Inspectors must ensure that the 1 inch (25 mm) thick, preformed expansion joint filler is held rigidly in position and extends the full-width of all lanes.  The preformed expansion joint filler must be the required height and must extend to the top of the base, or bottom of the new pavement, so that no concrete is permitted to flow under it.  Holes in the expansion joint filler must be neatly punched or drilled, and the dowels must fit tightly through the holes with no gaps in which concrete could flow through. 

The dowels are oiled 2 hours prior to placing the concrete with new form oil as is required for contraction joints.  After oiling, an expansion cap, also called a sleeve, is placed on the opposite ends of adjacent dowels (each dowel will have one cap, but on alternate ends) to create a void in the concrete to permit expansion movement.    The cap contains a crimp or stop that provides for the 1-inch (25 mm) void.  These caps must not be forced beyond the crimp; otherwise, the space for expansion will be compromised and the joint will not function properly.

The Contractor must provide adequate consolidation throughout the slab depth, adjacent to the preformed expansion joint filler, and around dowels by use of hand-held internal vibrators.  The top of the joint must be formed to a 1-inch (25 mm) wide and 1-inch (25 mm) deep opening, carefully edged using an edger having a 1/8-inch (3 mm) radius on top of the preformed expansion joint filler, and sealed with 705.04 joint sealer.

Contraction Joints (451.09.D)

Contraction joints in concrete pavement are constructed at right angles across a pavement lane unless otherwise specified by the plans.  These joints control cracking of concrete pavement that result from stresses from volume changes during curing of the concrete.  These joints are designed to transfer the loading from traffic from one slab to the next and require the use of dowel bars to accomplish this function.  These dowel bars are called load transfer devices.  Dowel bars can be pre-installed using dowel bar assemblies (basket assemblies) or can be installed using dowel bar inserters during slip form paving.

Dowels must be spaced at 12-inch (300 mm) centers beginning 6 inches (150 mm) from the longitudinal joint.  The spacing between the end dowel and the outside edge of the lane may be increased up to 12 inches (300 mm).  A dowel must be placed 6 inches (150 mm) from the outer edge of the pavement when the spacing between the end dowel of the basket and the outside edge exceeds 12 inches (300 mm).  Contraction joints are required to be spaced in the pavement at intervals not to exceed the maximum spacing indicated in Standard Construction Drawing BP-2.2 or the plan construction drawings.  The maximum contraction joint spacing for reinforced concrete pavement (Item 451) is 21 feet (6.5 m).  For non-reinforced concrete pavement (Item 452) and concrete base (Item 305), the maximum spacing is 15 feet (4.6 m).

To function properly, dowels must be placed parallel to the surface and parallel to the centerline of the pavement since expansion and contraction movements occur in this direction. 

Saw Cutting Contraction Joints

When a standard (water cooled diamond bladed) concrete saw is used to cut the contraction joint, the following applies:

·         Pavement ≤ 10 inches thick: Saw the joint to a minimum depth of one-fourth the specified pavement thickness.

·         Pavements > 10 inches (255 mm) thick: Saw the joint to a minimum depth of one-third the specified pavement thickness.

·         Saw joints 1/4 ± 1/16 inch (6 ± 1.6 mm) wide as measured at the time of sawing.

When using early-entry (dry cut, lightweight) saws, only use saw blades and skid plates as recommended by the manufacturer.  Perform the early entry sawing after initial set and before final set as follows:

·         Saw the joint 2-1/4 to 2-1/2 inches (56 to 63 mm) deep.

·         Saw joints approximately 1/8 inch (3 mm) wide as measured at the time of sawing.

Joints should be spot checked to make sure that the Contractor is sawing the pavement to the required depth.

Figure 451.X – Standard Water Cooled Saw (left), Early Entry Saw (right)

If a crack appears ahead of the machine during pavement sawing, it is an indication that sawing is late.  When such cracking is noted, stop sawing that joint immediately and move the saw ahead several joints.  Saw a joint, move ahead several more joints, and saw another joint.  Continue skipping three or four joints and sawing every fourth or fifth joint until sawing is back on schedule.  The presence of slight raveling indicates proper timing of sawing.  Saw every joint in order when sawing is back on schedule.  After sawing has been completed for the day’s production, the saw can be returned to saw the skipped joints.  The standby saw may be put into service to saw the skipped joints if an experienced operator is available.

This procedure of skipping ahead and sawing every fourth or fifth joint relieves the stresses that occur when the concrete hardens and shrinks during curing.  Once these stresses are relieved, the sawing of the in-between joints is not as critical, but should be done as soon as possible.

The following day, the pavement is normally subjected to expansive forces  when the temperature rises.  When temperatures drop during the evening of the following day, the pavement experiences shrinkage stresses and all joints originally bypassed must be sawed before these stresses result in random cracking.

A HIPERPAV analysis for each day’s paving is required to be completed by the Contractor.  HIPERPAV software is used to help determine the correct time for sawing and potential for early age cracking based on mix design, pavement configuration, and environmental factors.  HIPERPAV generates the critical stress-to-strength of the pavement for the first 72 hours after placement. Supplement 1033 provides HIPERPAV details.  HIPERPAV files must be provided to the Engineer prior to paving. If the critical stress-to-strength ratio is 98 percent or greater, the Contractor is required to modify the paving operation and rerun the HIPERPAV analysis. 

Generally pavement should be sawed the same day, usually 6 to 8 hours after placing.  Concrete placed late in the day may not harden to permit sawing until the next day, but sawing should be completed before the following late afternoon temperature change, as shrinkage will occur as temperatures drop.  The Contractor is responsible for determining the optimal sawing time to prevent uncontrolled cracking.

Joints in lanes adjacent to previously placed lanes that are tied together must be sawed as soon as possible to prevent uncontrolled cracking.  If a new lane is tied to an existing concrete pavement, which is expanding and contracting with changes in temperature, stresses will be transmitted to the new slab unless joints are sawed as quickly as possible.  The following provisions are important to obtain quality sawed joints in these areas:

·         All contraction joints in the previously placed lane of pavement must be in-line with those in the newly placed lane.

·         The joint sawing must be done as soon as the saw can be operated on the newly placed pavement lane without damaging or excessive raveling of the joint.

·         Full-depth joint cracking in the previously placed lane indicate movement.  Therefore, joints in the newly placed lane, which are in line with the cracked joints, must be sawed first.

·         The cut is to be made from the old slab to the outside or open edge of the new slab being sawed.

A sudden drop in temperature, wide variations in day and night temperatures, or a cold rain cause thermal changes and add stress, thus making the timing of sawing especially critical.   When these conditions occur or are anticipated, increased attention to the sawing operation to assure control of cracking is needed.

Construction Joints (451.09.E)

Construction joints are transverse joints placed at the conclusion of each day’s paving or when production is interrupted for more than 30 minutes.  These joints are formed by using an adequate bulkhead that provides a straight joint.  Construction joints in all concrete pavements are to be doweled and perpendicular to the centerline.  Construction joints may be located at a contraction joint or between contraction joints.  The bulkhead must have openings provided for individual dowels or a dowel basket assembly. The bulkhead must be shaped to conform to the typical section of the pavement.

Locate construction joints at or between contraction joints.  If located between contraction joints, construct the construction joint no closer than 10 feet (3 m) to the last contraction joint.

In non-reinforced concrete base (305), construction joints must not be closer than 6 feet (1.8 m) to another transverse joint.

At skewed joints between approach slabs and approach pavement, exercise care to position the dowels parallel to the centerline.  Recent experience indicates movement occurs at such joints. Make provisions for this movement by placing dowels the same as for contraction joints.

The joint may be hand-formed or sawed to the same dimensions required for transverse joints in adjoining pavement.

Figure 451.Y – Transverse Construction Joints Are Doweled

Smooth epoxy-coated dowels must be used in construction joints placed parallel to the surface of the base.  The dowel size and spacing is the same as required for standard contraction joints.  See 451.09.B for those details.

Finishing (451.10)

Finishing behind the concrete paving operation can be done by a variety of methods.  In all cases, a 10-foot straightedge must be used to continually check the pavement surface for smoothness. 

Paving operations may include floats of different configurations behind the paver.  Some slip form pavers include oscillating longitudinal floats or other types of “automatic” floats attached to the paver.  Regardless of the type of machine floating, a straightedge should be used to check the pavement surface.

The Contractor is required to round the edges of the pavement slab to the radius specified before the concrete sets.  For an inside slab edge, the radius is to be 1/8 inch (3 mm), and for an outside slab edge, the radius is typically 1/2 inch (13 mm).  Any tool marks left by the edging tool must be eliminated.

Some slip form paving machines trail several sections of forms while others have no trailing forms.  When trailing forms are used, they provide protection to the edges while the surface is straight edged.  However, straight edging should not be confined to the area of the trailing forms.

Final finishing is perhaps the most important step in the paving operation, at least from the public viewpoint, because it determines whether the final surface meets the necessary tolerance for a smooth riding surface.  Projects using high-strength, quality concrete and the best of modern paving equipment often end up with substandard surfaces, simply because of careless work and lack of attention to details during final finishing.

The work of the hand finishers will be simplified if forms or string lines are set accurately.  The finishing machines must also be adjusted and operated properly.  If finishing machines are not operated properly, additional work is required for the hand finishers to correct surface irregularities and to produce an acceptable surface that complies with the specifications.  The preferred method is to keep the machines in proper adjustment and limit the amount of handwork that is required.  In any case, it is up to the Inspector to insist that the finishers produce a pavement with the required smoothness and an acceptable uniform final surface texture.

The Inspector should ensure that the finishers check their hand tools before paving operations begin to make sure that they comply with specifications.  Straightedges should be tested with a string or a master straightedge to make sure they are straight.  Inspection of tools should be done daily to correct for wear.  Tools should be restored to the desired accurate form.  They must be rigid enough to remain straight with no bending while in use. 

After mechanical finishing, while the concrete is still plastic, minor irregularities and surface marks should be removed with a scraping straightedge.  When necessary, remove excess water and laitance from the surface transversely by means of a scraping straightedge.  Any such excess should be wasted over the forms or removed from the pavement edge if slip forming.

A number of different types of straightedges have been used satisfactorily.  They must be strong enough to maintain a true straightedge and yet light enough to handle.  In some cases, they must be heavy enough to cut or scrape off any high spots left by the machine finishing operations.  They must be a minimum of 10 feet (3.0 meters) long to comply with the specifications.

Figure 451.Z – Highway Straightedges/Bump Cutters behind the Automatic Float

The straightedge is operated from the side of the pavement transversely and should be advanced along the pavement in successive stages.  By proper manipulation, it can be used as a float to smooth the surface or as a cutter to remove high spots.  Long-handled floats may be used to smooth and fill in open textured areas in the surface, but this must be done before straightedge finishing.  The use of such floats should be held to a minimum.  If open textured areas persist, the aggregate grading, mix design, and the method of placing the concrete must be evaluated and corrected.  A properly proportioned mix along with correct paver operation should not require excessive hand floating.

No water is to be added to the surface during this or any other operation.  This includes sprinkling of water on the surface using a brush, spraying, or otherwise introducing additional water into the finishing process.  Adding water reduces the air entrainment in the surface causing a mortar layer that will not be resistant to freezing and thawing.  This thin weak surface layer will pop off over time.

Texturing

The final surface texture should be applied when most of the water sheen has disappeared, but before concrete becomes non-plastic.  Finishing methods used must produce the texture as described in the appropriate specification item.

Unless otherwise specified, concrete pavement (451 and 452) must be textured by the use of a broom drag in the longitudinal or transverse direction immediately followed by an approved device which produces a random pattern of grooves in the longitudinal direction.  The broom drag must produce a uniform, gritty texture.  Brooms suspended from a machine or truss and dragged over the pavement surface have provided satisfactory longitudinal texture.  The broom should be lifted clear of the surface when not being used.

Figure 451.AA – Machine Brooming in Longitudinal Direction (left), Transverse Direction (right)

Concrete base pavement (Item 305) must have a final surface finish that is a uniform, gritty texture as obtained with a broom drag in the longitudinal or transverse direction.  No grooves are put in base pavement because it is normally covered with asphalt concrete prior to opening it to traffic.

The broom drag provides a more skid resistant pavement.  The Department has found that new concrete pavement would lose skid resistance after one year of service with merely a light burlap drag prior to tine grooving.  Broom dragging roughens the area of concrete between grooves that results in a longer lasting skid resistance.

Immediately after brooming, the pavement is longitudinally tined using a uniform tine spacing of 3/4 inches, 1/8 inch wide, and 1/8 inch deep.  Longitudinal tining must be applied using a machine specifically made for this application and must be controlled from a stringline that controls the line and grade of the tining operation.  Longitudinal tining shall be kept 3 inches from the edge of pavement and any longitudinal joint.

Small areas, as defined by the Engineer, may be longitudinal tined with non-machine operations.  The finished longitudinal tining will be straight to within 3/4-inch in 20 feet (20 mm in 6.4 m).

Figure 451.BB – Longitudinal Tining

Station Numbers

The Contractor is required by specification to stencil complete station numbers into the plastic concrete pavement (Item 451 and 452) each 100 feet (50 meters) before the concrete sets.  The dies used to form the station numbers must be 3 to 4 inches (75 to 100 mm) high and 1/4 inch (6 mm) in depth.  The numbers are placed parallel to the pavement edge, centered 12 inches (0.30 m) from, and facing the right edge of the pavement.  For the purposes of placing station numbers, the right edge is the edge to the right of the normal direction of travel. 

The numbers should be impressed into the plastic concrete following the texturing of the surface and before curing is applied.  If the impression is made too early, the number will tend to close up and not be as distinct as desired. 

For divided highways, station numbers must be provided for each pavement direction.

If concrete shoulders are placed with a traveled lane, the station numbers should be placed 12 inches (0.3 m) in from the outside edge of the shoulder and facing the pavement.

Station numbers are not required on concrete base (Item 305).

Curing (451.11)

Curing is the treatment or protection provided to concrete during the curing period.  Proper curing consists of keeping the concrete moist and preventing rapid evaporation of the mix water to ensure adequate hydration of the cement.  Curing protects concrete from early shrinkage due to changes in temperature and/or loss of moisture before it has developed sufficient strength to resist the resulting tensile stresses.

It is extremely important to provide adequate curing during the first few days, with the first few hours being most important to obtain a strong durable pavement.  Strength loss due to lack of moisture during this period is difficult to regain even with subsequent curing.

During windy, hot, dry weather, it is very important that finishing is completed rapidly and the curing be placed before the surface dries out to the extent that plastic shrinkage cracks develop.  These cracks can never be sealed, and they are an indication that the surface may have been depleted of the necessary water to properly complete the chemical reaction of cement hydration.  Water curing may halt this shrinkage cracking, but the addition of more water will not correct the cracking once it occurs.

In cold weather, the concrete may continue to bleed after finishing.  Take care in placing any type of curing under these conditions so that the surface will not be marked.

Prior to the application of any curing material, ensure that it meets the requirements of 705.05, 705.06, or 705.07 Type 2.  This also applies to any equipment used in the application.

Liquid Membrane Curing

For concrete pavement, an approved curing membrane must be sprayed on all exposed surfaces using a self-propelled mechanical sprayer with adequate shielding to prevent overspray to adjacent areas from wind.  The curing membrane must be applied at a minimum rate of 1 gallon per 150 square feet (1 liter per 3.6 square meters) as soon as the free water has dissipated from the surface.  Approved liquid membrane curing compounds are white in color so that coverage can be readily observed.  They are sprayed over the exposed concrete faces while the concrete is still plastic.  Hand spraying can be used on pavement with integral curb, for small irregular areas, sections of variable width, and on pavement edges after form removal. 

Project inspection should include a daily check of the Contractor’s curing compound application rate to ensure that the correct amount of curing membrane was applied to the pavement.  To do this check, determine the amount of curing compound required for the day’s placement and compare it to the amount of curing compound actually used by the Contractor. 

To calculate the amount of curing compound required, the area in square feet (square meters) of pavement that is to be cured must be determined.  This area includes the top surface of the pavement plus the area of any pavement edges that are to be cured if the Contractor is slip form paving.  Once the area has been calculated, it is divided by the specified application rate in gallons per square yard (liters per square meter).  The formula below is used to calculate the required amount of curing compound in gallons (liters):

Required Gallons =     Area (square feet)        

Rate (gallons/ square feet)

Required Liters =        Area (square meters)        

Rate (liters/square meter)

The above equations give the amount of curing compound required in gallons (liters).  The amount of gallons (liters) required is compared to the amount that was actually used during the day’s work.  The amount of gallons (liters) of curing actually used must be equal to or greater than the required amount of gallons (liters).

If properly applied, these membrane-forming compounds prevent evaporation and the retained water provides excellent curing.  Therefore, make sure that the specified rate of application is adhered to and the curing compound is applied evenly.  This ensures that a uniform thickness of membrane coating is obtained.  If this is not done, the quality of the concrete pavement will be affected.  It should be noted that concrete with a grooved (tined) surface may require more curing compound to obtain complete coverage than a base pavement without tining.  The specified application rate is a minimum and the Contractor must use more if the visual coverage is lacking.

White pigmented compound is the only membrane curing compound acceptable on paving projects.  This has an advantage over clear type compounds in summer construction in that it provides a coating that reflects heat from the surface.  This decreases heat absorption in the pavement and the tendency for transverse cracks to develop during warmer afternoon temperatures.  In addition, its white color permits visual inspection for uniform coverage.

The white pigment used in the membrane acts as an abrasive that tends to enlarge the apertures of the spray nozzles and to reduce the efficiency of pumping equipment.  Equipment used to apply membrane should be cleaned frequently and checked to see that it provides a uniform protective covering.  Streaks, lines, and dribbles indicate malfunctioning sprayers.  The Contractor must correct the equipment to provide uniform, consistent coverage over the entire pavement.

Figure 451.CC – Cure/Texture Machine

Water Curing

A water cure using wet burlap, waterproof paper, or polyethylene sheeting may be used; however, this type of curing must remain in place for 7 days unless test beams have attained a modulus of rupture of 600 psi.  This type of curing should be placed as soon as possible without marring the surface.

The Contractor may choose to water cure by placing wet burlap on the exposed surfaces followed by waterproof paper or polyethylene sheeting.  Make sure that the pavement is kept wet at all times.  This type of curing requires constant checking throughout the curing period.  This method is not used very frequently; therefore, it is not discussed in detail.

Waterproof paper or polyethylene meeting specification requirements (705.05 and 705.06) are placed on the concrete as soon as possible after finishing, without marring the surface, and are left in place for the full curing period.

The combination of wet burlap and waterproof paper or polyethylene sheeting is less labor intensive than a burlap-only cure, because it will keep the concrete wet and does not require regular wetting. 

Curing blankets, sheeting, and burlap should be placed to cover the full lane width and lapped at least 12 inches (0.3 m).  Edges should be completely covered when forms are removed.  This may be done by turning down the edge of the blankets or narrow strips pulled out from under them.  These narrow strips are placed on the concrete before main sheets are laid.

Curing materials should never be dragged over fresh concrete and should be placed so as not to mar the surface.  One of the principal precautions in this curing method is to ensure edges along forms are sealed so there is no possibility of air getting under the curing material.  This is important because air can circulate over the pavement drying out the surface and resulting in inadequate curing.  In addition, heavy winds will get under the blankets and rip them off leaving the pavement without any curing at all.

All physical curing blankets, sheeting, etc., must be free of holes and torn areas and must be securely anchored against blowing.  These types of curing methods must be checked daily.

Removing Forms (451.12)

The presence of forms during early curing protects the pavement edges against damage and serves as a curing method (for the pavement edges only).

During warm weather, the common procedure is to remove the forms approximately 24 hours after the concrete is placed.  During cold weather, it may be advisable to leave forms in place for a longer period.   In any event, forms should not be removed until the concrete has attained sufficient strength to prevent damage to the concrete surface or breaking of the edges during removal.

The method used to remove the forms should not damage the concrete pavement.  In addition, the Contractor should be encouraged to use a method that will not bend or otherwise damage the forms.  The method used to move forms away from concrete should ensure that each form section is pulled horizontally away from the edge before it is lifted.

Pin keys should be loosened first, form joint locks unfastened, and nuts removed from the ends of hook bolts (single lane paving).  Then, pins should be removed from their sockets using a direct vertical lift without any pressure toward the concrete.  The action necessary to exert the vertical lift should be from the forms or the ground outside forms.  If any equipment is used to pull pins that may ride on the concrete, make sure that no pressure is on the concrete other than the weight of the equipment.

After pins are removed and other preliminary work finished, light blows with a hammer or careful prying on base flanges may be used to separate forms from concrete.  Prying against the concrete edges with bars to break forms loose should never be permitted.

When forms have been removed, edges should be checked immediately and honeycombed areas filled with mortar.  Inspect filled areas to make sure the entire areas are tightly packed and struck off flush with surface of the pavement edge.

Curing must be applied to the edges as soon as forms have been removed and edge patching has been completed.  This ensures curing was satisfactory as well as prevents  the loss of water necessary for hydration of the cement.

Surface Smoothness (451.13)

There are two methods that could be used to check the smoothness of a completed concrete pavement.  Item 451.13 requires the use of a 10-foot rolling straightedge or Proposal Note (PN) 420 that requires the use of a non-contact profiler to measure smoothness.  When PN 420 is required as part of the Contract documents, 451.13 does not apply.

When 451.13 applies, the Contractor is required to check the surface smoothness of the completed pavement using a 10-foot rolling straightedge or equipment conforming to Supplement 1058 and output using ProVal software conforming to PN 420 for a 25-foot localized roughness criteria (see the section on PN 420 below).  The rolling straightedge can be two- or four-wheeled with an indicator wheel in the center that detects high and low areas in the pavement surface. This equipment must alert the operator when encountering any high or low areas of pavement in excess of a preset tolerance. This alert may be by a pointer scale, by audio, or by marking the pavement surface with dye or paint.

Testing is done after the final curing and cleaning of the pavement to detect any surface variations that are in excess of the allowable tolerances. For pavements, the tolerance is 1/8 inch in 10 feet (3 mm in 3.0 m).  For ramp pavements, and for those pavements that exceed an 8 degree curvature or 6 percent grade, the tolerance is 1/4 inch in 10 feet (6 mm in 3.0 m).

Figure 451.DD – 10 foot Rolling Straightedge

The Contractor must tow or walk the equipment over the completed pavement.  The Contractor must test two lines, one in each wheel path, in each 12-foot (3.6 meter) lane.  The wheel paths are located 3 feet (1 m) measured transversely from the pavement edge on each side.

Proposal Note 420 – Surface Smoothness Requirement for Pavements

Larger concrete paving contracts (those exceeding 1 mile in centerline length) generally include Proposal Note (PN) 420 Surface Smoothness Requirements for Pavements.  When this proposal note is included, the provisions of 451.12 do not apply and the Contractor is required to use the information included in PN 420 to determine surface smoothness.  This proposal note requires testing of the surface of completed pavement with a non-contact profiler and ProVAL software that will produce an International Roughness Index (IRI).

The non-contact profiler must meet the requirements of Supplement 1058.  The equipment and operator must be previously approved by the Department.  All equipment and operators that are approved are listed on the Department’s website.  The equipment and Operator must be checked against the Contractor’s approval letter and against the Department’s website.  The Contractor must demonstrate the use of the equipment prior to its use on the project.

Figure 451.EE – Non-contact profilers

Low-speed type used for daily checks (left) and high-speed type for payment (right)

The Contractor is paid a bonus for exceptionally smooth concrete pavement and there are deductions if the pavement is not constructed smooth enough.  The pavement must be of a certain level of smoothness to be accepted, otherwise, corrective work is required.  The IRI is measured for localized roughness (bumps) for any 25-foot section and for smoothness of any 0.10 mile section.  Where there is localized roughness with an IRI greater than 160 inches per mile in 25 feet, corrective work is required.  For an IRI greater than the requirements of PN 420 (currently 95 inches per mile) in any 0.10 mile section, corrective work is also required. 

Defective work, as described under PN 420, includes removal and replacement or diamond grinding to restore the surface to within the tolerances required.

Profile Grinding (451.14)

When 451.13 applies, and the surface deviations as measured with the 10-foot rolling straightedge must be ground, the diamond grinding equipment must conform to Item 257.  Bush hammering, carbide tipped grinders, or any method that may damage the bond of the aggregate or shatter the aggregate is not permitted.

A 10-foot (3.0 meter) straightedge must be used to check for compliance when corrective work is in progress.  The straightedge can be used to determine the transverse limits of the area to be corrected.  Usually variations extend beyond the wheel path and may require diamond grinding and grooving the entire lane width.  This determination can only be made by checking with a straightedge.

Low areas should be corrected by grinding on each side until within tolerance.  If these areas cannot be corrected by grinding, they must be repaired or replaced to the satisfaction of the Engineer.

Pavement Grooving Corrections (451.15)

It may be necessary to restore grooves in concrete pavement after the concrete has hardened when the finishing operation does not conform to 451.10 and/or when the tining operation does not provide the correct pattern or depth.  Grinding to restore trueness leaves a corduroy texture in the longitudinal direction.  The randomly spaced transverse grooves must be restored as detailed to the dimensions given in 451.10. 

The equipment required for transverse grooving must be self-propelled, power driven machines specifically designed to groove hardened concrete pavement with diamond impregnated blades or diamond impregnated cylinder rings.  The blades or cylinder rings must be mounted on an arbor head so the resulting grooves are randomly spaced.  The grooving equipment must have a depth control device that detects variations in the surface and adjusts the cutting head to maintain the proper groove depth.

Note:  When pavement is ground to meet the requirements of 451.13 Surface Smoothness or PN 420, the restoration of transverse grooving is not required. 

Sealing Expansion Joints (451.16)

Only expansion joints are required to be sealed.  This should be done as soon as possible after saw cutting and before the pavement is open to construction equipment or any other traffic.  Proper sealing prevents intrusion of stones and debris into the joint that would keep it from opening and closing as designed with the movement of the pavement. 

The Engineer may allow the use of a temporary seal material to allow opening to traffic.  This material must be removed prior to the final sealing of the joint. 

All joints must be cleaned prior to filling.  Cleaning consists of operating a saw blade backward through the saw groove to remove all pebbles, trash, dirt, etc.  Any other operation which satisfactorily cleans the groove is permissible.  The final step in cleaning consists of blowing out the joint opening using compressed air or by a jet of clean water.

Hot-applied joint sealer (705.04) is required for sealing expansion joints.  Since the hot applied sealer requires heating, frequent checks should be made to avoid overheating to a temperature higher than the manufacturer’s recommendation. 

Joint walls must be inspected just ahead of filling to make sure that they are dry and thoroughly clean.  It is essential that the walls be in this condition if the sealer is to function properly.  If the sealer fails to adhere to the concrete, water and foreign material will enter the joint.

Pour liquid sealing compounds in such a manner that complete filling from the bottom of the joint slot to approximately level with the surface of the pavement is assured.  With some compounds it may be necessary to fill the joint in several applications.  Workers should not allow the sealing compound to spatter or drip onto the adjacent pavement.

The sealing material will run to the low side if the joint is filled too fast.  Hot poured compounds may flow out of the joint at the edge of the pavement if some method of plugging the edge is not used. 

As air temperature increases, the pavement will expand or lengthen and the joints will close.  Conversely, the slabs contract as the temperature falls, causing the joints to open.  Joint filling should be such that the surface of the hot-applied sealing material will be approximately level with the pavement surface when the pavement temperature is about 70 °F (21 °C).

Never over-fill a joint to the extent that a bump will be produced at the joint.  Such a practice is a waste of material, creates an unsightly condition, and affects the riding quality of the finished pavement.  The bumps created by the excessive material will be readily noticeable to the traveling public from a smoothness standpoint as vehicles pass over each joint.

Prior to final acceptance of the pavement, any unsatisfactory joint seal should be removed and replaced.  All low spots in sealing compounds must be brought to the desired level, and any high spots should be cut off and the excess material removed.

Opening to Traffic (451.17)

The completed pavement may be opened to traffic, including construction traffic, after 7 days have elapsed. The pavement may be opened to traffic after 5 days provided the modulus of rupture of the test beams is 600 pounds per square inch (4.2 Mpa) or greater.

If it is determined that it will be necessary to open a portion of the pavement in fewer than 5 days, high early strength concrete shall be used, and the pavement may be opened to traffic after 3 days provided the test beams attain a modulus of rupture of 600 pounds per square inch (4.2 Mpa) or greater.  In no case should concrete pavement be opened in less than 3 days.

Concrete test beams are required for each 7,500 square yards (6,500 square meters), or fraction thereof, of pavement placed each day.  Instruction for making and testing beams are found in Item 499.  Beams are tested at the project by the project personnel.

Beams normally are tested at 5 and 7 days.  If results are not needed before the end of 7 days, only one beam break is necessary.  This break should be made at the age of 7 days.

The maximum capacity of the beam breaker is 1,000 pounds per square inch (6.7 Mpa) and is marked on the beam breaker dial.  The capacity must not be exceeded.  Beams that do not break when loaded to the capacity of the breaker should be recorded as >1,000 psi (>6.7 Mpa) or whatever the unbroken strength was when the test was stopped, such as 850 psi + (5.9 MPa +) for example.

Slump, air, and yield tests shall be made and recorded each time beams are cast.  Concrete for these tests shall be obtained from the same batch of concrete that was used in casting the beams.

The Contractor is responsible for repairing cracked or deficient pavement at no cost to the Department.  These deficiencies include:

·         Transverse or diagonally cracked full-depth pavement.

o    There is an exception for reinforced 451 pavement that accepts a tight, mid-panel transverse crack.  See 451.17.

·         Longitudinal cracked full-depth pavement.

·         Spalled pavement surfaces.

·         Pavement panels which have cement or mud balls.

Repair methods are specified in 451.17 and include the following:

A.      Transverse or diagonally cracked full-depth pavement.

        Repair with a full-depth repair according to Item 255 and applicable standard construction drawings. Repair cracks by replacing the pavement the full-width and full-depth between longitudinal joints, perpendicular to the centerline, and at least 6 feet (1.8 m) longitudinally.   Install smooth dowel bars at the interface between the original pavement and the replaced pavement section.  Locate and size the repairs to ensure that the repair limits are at least 7 feet (2.1 m) away from any transverse joint.  Item 255 and Standard Construction Drawing BP-2.5 applies.

B.       Longitudinal cracking cracked full-depth pavement. 

        Repair longitudinal cracks within 15 inches (380 mm) of a tied longitudinal joint by routing and sealing the crack according to Item 423.  For longitudinal cracks beyond 15 inches (380 mm), repair the same as for transverse or diagonal cracks stated above.

C.       Spalled pavement surfaces. 

        Repair spalled pavement with Item 256 Bonded Patching of Portland Cement Concrete Pavement.

D.      Pavement panels which have cement or mud balls. 

Repair cement balls or mudballs by coring out the area, full-depth with a diamond core bit, and replacing the removed concrete with the same concrete as in the pavement.  Remove and replace any pavement panel with 5 or more cement balls or mudballs.  Locate the limits of the repair along the longitudinal joints and at least 1 foot (0.3 m) past the transverse joints to remove any existing dowel bars.  Install smooth dowel bars at the transverse limits of the repairs.  Install Type D (Drilled Tied Longitudinal) Joint along the longitudinal limits.

Pavement Thickness (451.18.A)

The Contractor must cut cores from the completed pavement to check the pavement thickness and to determine a price adjustment if necessary. When the constructed pavement thickness is less than plan by more than 0.2 inches, a deduction to the contract bid unit price is made. 

One random core must be taken for every (sublot) 2,000 square yards (1,650 square meters) of a pavement unit or a major fraction thereof.  No less than three cores will be cut for any pavement unit.  For the purpose of coring, the Department will consider the entire pavement area of a specified thickness a unit.  The Engineer will determine the locations for the random cores according to Supplement 1064. 

Core thickness must be measured by the Engineer in accordance with AASHTO T 148.  When a core shows a deficiency in thickness of more than 1/2 inch (13 mm) from the specified thickness, the Contractor must take additional cores as directed by the Engineer to determine the limits of the deficiency.   Follow the procedures below to determine how and when to cut additional cores:

1.        Take a core 5 feet (1.5 m) longitudinally on both sides of the deficient core.  If both cores are less than 1/2 inch (13 mm) deficient in thickness, the zone of deficiency has been determined. 

2.        If either or both cores are more than 1/2 inch (13 mm) deficient in thickness, cut a core 50 feet (15 m) longitudinally from the deficient core(s).  If  the 50-foot (15 m) core(s) is more than 1/2 inch (13 mm) deficient, cut additional cores in 100-foot (30 m) longitudinal intervals until a core is less than 1/2 inch (13 mm) deficient in thickness, until the pavement ends, or until overlapping an adjacent pavement lot’s core in the same lane.

3.        If a pavement sublot has cores more than 1/2 inch (13 mm) deficient in thickness, and the sublot’s constructed width is greater than 12 feet (3.6 m), obtain cores transverse to the location of the more than 1/2 inch (13 mm) deficient cores.  Obtain transverse cores at a location one-half the distance from the deficient core to the furthest edge of pavement.  Obtain transverse cores for each core more than 1/2 inch (13 mm) deficient in thickness.

4.        The Engineer will use the cores that measure less than 1/2 inch (13 mm) deficient in thickness to define the limits of the deficiency.  The price adjustment would apply to these limits of deficiency.  Note: The zone of deficiency is also called zone of deficient thickness.

Pavement Strength (451.18.B)

Whether the concrete pavement item is “with QC/QA” or not, additional strength cores will be obtained from the sample location as the thickness cores. 

The Contractor is required to obtain the cores at the same location as 451.18.A for the Engineer.  The Contractor determines when he wants all the cores tested (from 28 to 90 days) and notifies the Engineer.

If the concrete is QC/QA the Contractor’s laboratory performs the QC core testing conforming to the accepted QCP and Item 455.  The Engineer will require a QA core be obtained for every 10 sublots for verification testing.  Those QA cores will be provided to the Engineer for curing and testing by the District Laboratory.  The Department will test the core at the number of Contractor specified days.  QA Results are compared to the companion Contractor QC core result.  Acceptable results are defined in Item 455. 

An average strength and a standard deviation are calculated using the Contractor’s verified QC core results.  Follow the procedures of Supplement 1127.

If the concrete is not QC/QA, the Department will obtain the strength cores from the Contractor and the District Laboratory will perform the testing of the cores for acceptance.  Strength acceptance will be based on the individual core results not an average and standard deviation.

Price Adjustments (451.19)

Pavement Thickness (451.19.A)

Price adjustments are based on the pavement average thickness.  The pavement is to be constructed such that the thickness is not more than 0.2 inches (5 mm) less than the specified thickness at any location.  When this criterion is met, the Contractor receives 100 percent of the contract bid price. 

When a core or cores are greater than 1 inch deficient in thickness, the pavement must be removed and replaced.  The Zone of Deficiency for the removal is determined as outlined above.

For zones of deficiencies with pavement thickness 1/2 inch to 1 inch deficient, the Engineer must calculate the average thickness of concrete pavement to determine price adjustments.

Two averages must be calculated as follows:

1.        Calculate a Project Average Thickness (PAT) using all cores from all lots that are ≤ 1/2 inch deficient in thickness.

2.        Calculate a Deficient Zone Average (DZA) using all cores with a thickness deficiency of >1 1/2 inch.

Note:  When calculating PAT, cores > 1/2 inch thicker than the plan thickness are considered to be plan thickness + 1/2 inch for the PAT calculation.  For example, if plan thickness is 10 inches and the core measured 10.75 inches, use 10 inches + 1/2 = 10.5 inches when calculating the PAT.

The PAT and DZA are used to determine the price adjustment for each section of deficient pavement using the zone of deficiency area previously determined based on the coring operation.

The following table illustrates how the price adjustment is applied:

Table 451.17-1 Concrete Pavement Deficiency

Deficiency in Thickness

as Determined by Cores

Proportional Part

of Contract Price

0.0 to .2 inch (0.0 to 5 mm)

100 percent

0.3 to 0.5 inch (6 to 13 mm)

0.6 to 1.0 inch (15 to 25 mm)*

Greater than 1.0 inch (25 mm)

Remove and replace

*  The District Construction Administrator will determine whether pavement areas from 0.6 inch (15 mm) up to 1 inch (25 mm) deficient in thickness will be allowed to remain in place at the reduced price or must be removed and replaced. 

If any deficient core is greater than 1 inch (25 mm) deficient in thickness, determine the limits of over 1 inch (25 mm) deficiency by following 451.17, Steps 1 through 4, to determine the limits. Remove and replace those areas greater than 1 inch (25 mm) deficient in thickness.

The Contractor must fill all core holes using the same concrete used in constructing the pavement.  When filling the core hole, the surface should be damp and should be painted with a grout consisting of cement and water having the consistency of a thick paint.  Stiff concrete should then be rodded into the core hole before the grout dries.  The surface should be struck off, and curing membrane applied to provide curing essential for a durable repair.

The pavement areas represented by the PAT of DZA are to be calculated and paid separately.

Deductions are determined and applied to each separately placed width of pavement.

If any pavement area is removed and replaced, the replaced pavement must be cored, and core values determined are to be included in the average calculations.

Example:

A Contractor places 150,000 square yards of 10-inch concrete pavement.  The contract price is $38 per square yard.  If the Project Average Thickness (PAT) is 9.7 inches and the Plan Specified Thickness (PST) is 10 inches, what would the Contractor be paid?

The thickness deficiency is:  10 inches – 9.7 inches = 0.3 inches

From Table 451.17-1, look up the price adjustment for a 0.3 inch thickness deficiency.

Use that formula to determine the Proportion Part of Contract Price as follows:

Proportion Part of the Contract Price  =  = 0.8330

Then the Contractor’s Payment for 150,000 sq. yards is calculated as follows:

(150,000 sq. yards) x ($38.00 per sq. yards) x (0.8330) = $4,748,100

Note: this results in a deduction of $951,900 for this pavement area.

Concrete Strength (451.19.B)

Record the compressive strength results for each sublot of concrete.  High-early strength mixes, QC MS and QC FS mixes, are calculated separately.  Determine the strength pay factor according to Table 451.19-2.

TABLE 451.19-2

CONCRETE PAVEMENT STRENGTH PAY FACTOR

Design  Strength = f’c from 499 or as per plan

Individual Sublot Core Strength = x

Project Average Strength () =

Project Standard Deviation (δ) = 

Project Required Strength (f’cr) = f’c + 1.65 δ

Strength Pay Factor (PFS) =  / f’cr *

* When PFS is greater than 1.00, pay the unit bid price

For high-early strength sublots, determine the pay factor separately as follows:

·        If the individual sublot core strength (x) is greater than f’c,  

PFS = 100% of the Unit bid price for the quantity represented.

·        If the individual sublot core strength (x) is less than f’c, then

PFS = /f’c) of the unit bid price for the quantity represented.

Pavement Smoothness (451.19.C)

When the Project plans include Proposal Note 420 determine a lump sum payment adjustment following the requirements of Proposal Note 420.

Multiple Deficiencies (451.19.D)   

When a pavement exhibits multiple deficiencies for thickness and strength, the reduced unit price will be calculated for each deficiency and the lowest reduced unit price will be used.  Adjustment for smoothness under 451.19.C will conform to the lump sum requirements of 451.19.C.

Method of Measurement (451.20)

Concrete pavement is measured by the number of square yards (square meters) completed and accepted in place.  The width of pavement used to calculate the area equals the pavement width shown in the typical sections of the plans.  The Engineer will measure the length along the centerline of each roadway or ramp.

Irregular areas of pavement should be field measured and the area calculated in square yards (square meters) for payment.

Any plan changes that involve concrete pavement quantities must be shown fully documented.  In addition, any areas found to be deficient in thickness must be documented and the adjustment made in the pay quantity.

Basis of Payment (451.21)

Payment is made for accepted quantities of pavement by the square yard (square meter) at the contract bid price.  If pavement is found to be deficient in thickness or compressive strength, the Department will pay a reduced price according to 451.19.

Multiple Deficiencies

When a pavement exhibits multiple deficiencies for thickness and strength, the reduced unit price will be calculated for each deficiency and the lowest reduced unit price will be used.  Adjustment for smoothness under 451.19.C will conform to the lump sum requirements of 451.19.C.

There is no additional payment for any pavement constructed and found to have an average thickness in excess of the thickness specified.

Documentation Requirements - 451 Reinforced Portland Cement Concrete Pavement

1.        Document subgrade/subbase preparation.

2.        Document contraction, expansion, and longitudinal joints dowel and tiebar sizes, type, coating, support, placement, and spacing.

3.        Document forms set 100 percent bearing, correct alignment and grade, rigid, clean and oiled.

4.        Document length of lap, clearance maintained on steel mesh.

5.        Document contraction joint spacing, dowels oiled, dowel assembly tie wires removed, number and size of pins used to hold dowel assembly, and alignment of dowels.

6.        For slip form construction document:

a.        Test section results.

a.        Approval of slip form paver.

b.        Alignment of dowels using MIT Scan-2.

c.        Corrective action as required.

7.        Document concrete placement, including all quality control testing, method of placement, finishing, tining, curing (type and amount), stamping of stationing, and weather conditions.

8.        Document use of HIPERPAV software, time of sawing, depth, and width of sawed joints.

9.        Document coring for thickness verification and results.

10.     Record results of beam breaks and opening to traffic.

11.     Measure length and width for pay.

12.     Document on CA-D-3A or CA-D-3B or other approved forms.

452 Non-Reinforced Portland Cement Concrete Pavement

Description (452.01)

This item of work involves construction of a non-reinforced Portland cement concrete pavement on a prepared surface.  The same methods and practices are utilized in the construction of 452 Pavement with some exceptions listed below.  The major difference between 451 and 452 Pavement is the elimination of the steel reinforcing mesh in the 452 specification.

Construction (452.02)

Non-reinforced Portland cement concrete pavement is constructed in accordance with 451 with the following exceptions:

1.        Reinforcing mesh specified in 451.08 is not required.

2.        Dowels are required in transverse contraction joints in mainline pavement, ramps, acceleration/deceleration lanes, and collector/distributor lanes, but not in concrete shoulders adjacent to the above-listed pavements unless the contraction joints are within 500 feet (150 m) of a pressure relief joint. 

3.        The spacing of contraction joints in 452 is 15 feet (4.6 m) unless the 452 Pavement is placed as a shoulder tied to 451 or 305 Pavement.  In this case, the joints in the 452 Pavement must match the spacing, alignment, sawing, and sealing requirements of the adjacent pavement.

4.        Construction joints in 452 Pavement must not be located closer than 6 feet (1.8 m) from another parallel joint.

Method of Measurement (452.03)

Non-reinforced Portland cement concrete pavement is measured by the square yard (square meter) of pavement completed and accepted.  All of the provisions of 451 method of measurement apply to 452.

Basis of Payment (452.04)

Payment for 452 Pavement is the same as for 451 Pavement.  Payment is made for accepted quantities of pavement by the square yard (square meter) at the contract bid price.  If pavement is found to be deficient in thickness or compressive strength, the Department will pay a reduced price according to 451.19.

There is no additional payment for any pavement constructed and found to have an average thickness in excess of the thickness specified.

Documentation Requirements - 452 Non-Reinforced Portland Cement Concrete Pavement

1.        Document subgrade/subbase preparation.

2.        Document contraction, expansion, and longitudinal joints dowel and tiebar sizes, type, coating, support, placement, spacing.

3.        Document forms set 100 percent bearing, correct alignment and grade, rigid, clean and oiled.

4.        Document length of lap, clearance maintained on steel mesh.

5.        Document contraction joint spacing, dowels oiled, dowel assembly tie wires removed, number and size of pins used to hold dowel assembly, and alignment of dowels.

6.        For slip form construction document:

a.        Test section results.

b.        Approval of slip form paver.

c.        Alignment of dowels using MIT Scan-2.

d.        Corrective action as required.

7.        Document concrete placement, including all quality control testing, method of placement, finishing, tining, curing (type and amount), stamping of stationing, and weather conditions.

8.        Document use of HIPERPAV software, time of sawing, and depth and width of sawed joints.

9.        Document coring for thickness verification and results.

10.     Record results of beam breaks and opening to traffic.

11.     Measure length and width for pay.

12.     Document on CA-D-3A or CA-D-3B or other approved forms.

455 Quality Control Plan, Testing, and Assurance for QC/QA Concrete

Description (455.01)

Use this specification for Items 451, 452, 305, and 511 when the bid item description requires QC/QA.  This specification defines the minimum Quality Control Plan (QCP) requirements, the Contractor’s minimum quality control (QC) materials testing, and the Department’s quality assurance (QA) materials verification testing requirements.

The Contractor will develop a QCP to ensure that all materials and construction practices for the item will conform to the specifications.  Establish the responsibilities, duties, and frequency for both in-process controls and quality control testing at the concrete’s source and at the job site. This plan is to be reviewed by the Engineer for compliance and then accepted. See 455.06 for the submission time requirements for the Contractor’s QCP.

Quality Control Plan Basic Requirements (455.02)

This section outlines the minimum QCP requirements for any QC/QA Concrete that is to be produced. The QCP submitted by the Contractor should, at a minimum, contain the content listed in 455.02. The QCP should be reviewed by the Engineer for compliance with this section. The Engineer also should ensure that the content of the QCP is acceptable prior to approval.

Additional Quality Control Plan Requirements for Structures (455.03)

This section outlines the additional requirements that must be added to the Contractor’s QCP when placing concrete for structures under Item 511. The Engineer should review the QCP to ensure that at a minimum, each item listed in 455.03 is contained in the QCP and is acceptable prior to approval. While most of the items listed in 455.03 have clear and definable measures, the following list provides some additional guidance on specific items:

Material Control Requirements

Ensure the QCP defines Lots and Sublots in accordance with 455.03 A. Approach slab concrete would be included with the lots for superstructure deck concrete, except parapet concrete would be considered separately. There should be at least three sublots of not more than 50 cubic yards in a lot. Ensure the QCP meets the minimum requirements of 455.03 A, including sampling, testing, and documenting Air Content, Slump, and Compressive Strength. Sample concrete at point of discharge and placement. All curing, transporting, capping and testing of compressive strength cylinders shall conform to ASTM standards. An AMRL laboratory must perform the compression testing. If the Contractor is proposing to use maturity for falsework removal and opening to traffic, they must provide the maturity curve per Supplement 1098.

Construction Process Quality Control Requirements

Ensure the QCP provides the minimum information required by 455.03 B, including procedures, methods and equipment to deliver, place, consolidate, finish, protect, cure and groove the structural concrete.

Reporting

This section lists the QC testing information that should be provided to the Engineer. The air content results must be sent to the Engineer within 1 day of completing the testing, and the compressive strength results within 5 days of completing the testing.

Additional Quality Control Plan Requirements for Concrete Pavement (455.04)

This section outlines the additional requirements that must be added to the Contractor’s QCP when placing concrete for pavements under Items 305, 451, or 452. The Engineer should review the QCP to ensure that at a minimum, each item listed in 455.04 is contained in the QCP and is acceptable prior to approval. While most of the items listed in 455.04 have clear and definable measures, the following list provides some additional guidance on specific items:

E.       Division of Pavement into Lots:  Ensure the QCP defines Lots in accordance with 455.04 A and Supplement 1064.

F.       Division of Lots into Quality Control Sublots: Ensure the QCP provides the placement sequence and placement widths for the pavement work. Ensure the QCP defines the sublots in accordance with 455.04B and Supplement 1064.

G.      Material Control Requirements: Ensure the QCP meets the minimum requirements of 455.04 C. Plant verification intervals for portable plants should be defined by the Contractor but may require modification if issues arise during production. Tests performed during paving operations should at least comply with the minimum requirements but could be more frequent.  

H.      Pavement Cores for Compression and Thickness:  Ensure the QCP provides the minimum information required by 455.04 D. per 451.18, B Strength cores must be tested at 28 to 90 days of age. The QCP should define the age for obtaining and testing cores within these limits.

I.         Concrete Strength: The QCP should  state the AMRL accredited laboratory that test core strengths. The Engineer should validate the accreditation and approve the reporting time frame and method.

J.        Construction Process Requirements:  Most of the items listed in 455.04 F have specific requirements from 305, 451, or 452 that must be met. The Contractor’s QCP should not only list the requirements from the related specification, but also state the methods, materials, and/or equipment that will be used to ensure compliance. The Engineer should cross-check each item listed with the related specification prior to acceptance. 

K.       Reporting Requirements:  This section lists the daily QC testing information that should be provided to the Engineer. The Engineer should approve the forms and methods used to transmit the information and to whom it will be sent.

Department Quality Assurance (455.05)

The Engineer will perform Quality Assurance sampling and testing as specified or as deemed necessary. Following proper procedures in determining random sample locations, sampling, handling, and testing are vital to the process. The results of this testing will be used to validate or invalidate the Contractor’s QC sampling and testing for payment.

Structure Concrete

Random Number Determination

The Engineer should use the table in Supplement 1127 or a random number generator to determine a random number for each sublot to determine from which load the QC sample will be taken. The Contractor should not be made aware of the QA random sample locations until just prior to sampling.

Slump and Air

The Engineer will perform side-by-side air and slump field testing with the Contractor and compare results. If the difference between the Department’s and the Contractor’s test result is greater than the tolerances listed below, the Contractor and Engineer will determine the reason for slump or air content differences and make necessary adjustments. The Engineer may stop the placement until the reason for the difference is established and corrected. The Engineer will check one of the first three loads delivered. Once the results are within the tolerances listed below, the Engineer may reduce the QA sampling and testing frequency to 10 percent of the Contractor’s subsequent QC tests.

Slump ±1 inch (25 mm)

Air Content ±1%.

Compressive Strength

The Engineer will obtain compressive strength QA samples from the same location as the Contractor’s quality control samples at a frequency of one QA sample for every 10 sublots or at least one per lot. The Engineer will make six 4- by 8-inch (100 x 200 mm) cylinders for each sample. The Engineer will mark the cylinders with identification and the Contractor shall provide initial curing at the project.

After the initial curing at the project site, deliver three QA cylinders to the Department’s Laboratory and three QA cylinders to the AMRL accredited laboratory for standard curing and testing.  The Accredited Laboratory will test the QA sample and the QC sample and report the test results on the form accepted by the QCP. Distinguish the QA from the QC results for the sublot.

The Engineer will compare and verify that the Department tested QA, Contractor tested QA, and the matching QC test results are within 14 percent of the Departments QA result. If the comparison is favorable, the Contractor QC testing is considered verified.

When the comparison of the results are more than 14 percent, investigate the results with the Engineer to determine the reason for the difference.  If the reason for the difference cannot be determined to the Engineer’s satisfaction, the Engineer will require the Contractor to either non-destructively test or core the concrete represented by the cylinder tests to determine compressive strength. Hire an independent laboratory to perform this additional testing. The Engineer will witness the testing and evaluate the results. The Department will reimburse the Contractor for all testing costs when the Department’s results are in error. If the QC results are found to be valid, use the QC results.  If the QC results are not valid, use the core results to determine the compressive strength values for pay factors, 511.22.

Pavement and Base Concrete

Air Content

The Engineer should randomly choose at least 10 percent of the Contractor’s QC samples to perform side-by-side quality assurance testing of the air content. The results of the Department’s and Contractor’s tests should compare to within ±1 percent. If the results do not compare, the Engineer should stop placement until the reason for non-comparison is determined and corrected.

Compressive Strength

The Engineer will randomly select  one out of every 10 Contractor QC core locations to have an additional core obtained as a QA strength sample according to Supplement 1127.  The Engineer should monitor the cutting and take immediate possession of the QA core. The QA core sample will be cured and tested on the date specified by the Contractor. If the Department’s QA core results the matching Contractor’s QC core results compare to within 13 percent, the Contractor QC is verified. If the results do not compare to within 13 percent, follow the procedure as outlined in 455.05.

QCP Submittal and Corrective Action (455.06)

The Contractor should submit the proposed QCP to the Engineer for acceptance at least 10 days prior to placing concrete.  If the submission is not found acceptable, the Contractor is required to revise and resubmit the QCP and allow another 10 days for review and acceptance. This may require the Contractor to reschedule a concrete pour.

The QCP acceptance is based on the concept that the proposed QCP procedures will provide work which meets all specification requirements.  If the accepted QCP is not being followed, the Engineer will require compliance or resubmittal of any modifications for review and acceptance. 

When the actual work produced by the QCP does conform to specification requirements, the Engineer will require modification of the QCP to return the work to conformance.  The Engineer must notify the Contractor when QCP modifications are required and work should not continue until the Engineer has accepted the QCP changes proposed by the Contractor.

Basis of Payment (455.07)

The cost of developing and implementing the QCP is incidental to the cost of the concrete sold with the QC/QA requirement.

Documentation Requirements - 455 Quality Control Plan, Testing, and Assurance for QC/QA Concrete

1.        Document all submission, rejection, acceptance, notification, or revision dates for the Contractor’s QCP.

2.        Document the date of receipt of all Contractor QC reports. 

a.        Document the quantities of concrete for payment and the test results in a Site Manager Sample. 

                                                               i.      When documenting Contractor test results, only input test screen. When reporting Contractor reported test results, only complete test screen PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS.

3.        Document the random number, sample location, date, test results, and comparison results for all QA samples obtained and tested.

4.        Record results of beam breaks and opening to traffic.

5.        Document on CA-C-2 or other approved forms.

499 Concrete – General

Control of concrete is divided into two categories: large quantity critical usage and small quantity non-critical usage.  All pavement and structure concrete, and in general any other concrete usage exceeding 200 cubic yards (150 cubic meters) per day, is considered large quantity critical usage.

When placing small quantity non-critical usage concrete from sources having a record of supplying approved material, the concrete may be accepted by field tests and backed up by random test beams, concrete cylinders, and random plant inspections as deemed necessary by the Engineer.  The following list shows examples of small quantity non-critical usage concrete:

1.        Sidewalks - Not to exceed approximately 500 square yards (418 square meters) per day.

2.        Curbing, combination curb, and gutter - Not to exceed approximately 500 linear feet (152 linear meters) per day.

3.        Patching and temporary pavements.

4.        Building foundations and floors.

5.        Slope paving and paved gutter.

6.        Guardrail and fence post anchorages.

7.        Metal pile castings.

8.        Culvert headwalls.

9.        Catch basins, manhole bases, and inlets.

10.     Sign, signal, and light bases.

Acceptance of concrete under the small quantity non-critical usage procedure does not waive the responsibility for using approved materials.  Concrete accepted under these provisions must be reported using an abbreviated TE-45 form along with company tickets indicating quantity, class, slump, and air test results and time of batching.

At least one concrete control inspector must be present whenever small quantity non-critical usage concrete is being placed and two or more inspectors are required for large quantity critical usage placement.

Introduction

Concrete used in highway construction is a mixture of coarse aggregate, fine aggregate, Portland cement, water, entrained air, and permissible mineral or chemical admixtures.  In this mixture, each aggregate particle is completely coated by a paste of cement and water.  This paste binds the aggregate particles into a mass called concrete.  The cement paste can consist of Portland cement, fly ash, ground granulated blast furnace slag, or microsilica, water, air voids, and any admixtures.  The cement paste comprises from 25 to 40 percent of the total concrete volume.  To have quality concrete, it is necessary that both aggregate and paste be sound and durable.

Aggregate, cement, and admixtures to be used in concrete are sampled and tested by the Laboratory to ensure that ingredients meet quality standards.  However, the quality of the paste depends on proper construction techniques.  These techniques include the minimum use of water and favorable temperature and humidity during the curing period.

Approximately 30 pounds of water is required to complete the chemical reaction with 100 pounds of cement.  Although a small amount of water is needed to complete the chemical reaction with cement, additional water is necessary to make the concrete workable.  As the paste is thinned out with water, its quality is lowered: it will have less strength and less durability.  For quality concrete, a proper proportion of water and cement is essential. This proportion is called water-cement ratio. The water-cement ratio is determined by dividing the weight in pounds (kilograms) of the total actual mixing water by the weight in pounds (kilograms) of cement used in the mix.  A maximum water-cement ratio is specified to avoid excess water and to ensure quality paste, and therefore, quality concrete.

To provide a dense mixture of the aggregate, cement, and water, it is necessary to have various sizes of aggregate particles so that the smaller particles fill the voids between the larger particles. Therefore, aggregate is divided into two categories: coarse aggregate and fine aggregate. Coarse aggregate is aggregate with 95 to 100 percent of its particles larger than the 4.75 mm (No. 4) sieve.  Fine aggregate is aggregate with 95 to 100 percent of its particles smaller than the 4.75 mm (No. 4) sieve.  Coarse and fine aggregate are graded, that is, they contain several sizes of particles combined together. When placed in concrete, these various sizes of particles become coated with the cement paste and form a dense mass with the voids filled. 

In addition to requirements that it be strong and dense, concrete must be durable. Durability means resistance to the elements.  Concrete that is not exposed to the elements such as water, freezing, and thawing, generally will be durable.  When non-durable concrete is subjected to these destructive forces, scaling and deterioration generally follows and progresses with each cycle of freezing and thawing unless preventive measures are taken.  In order to provide concrete with additional durability, an air-entraining admixture is added to the concrete to generate billions of air bubbles of microscopic size in the concrete.  This air-entraining agent may be interground with the cement, or it may be an admixture, or both.  These microscopic air bubbles form in the paste of the concrete as it hardens and create tiny air pockets in the hardened concrete. When moisture is present and freezing takes place in air-entrained concrete, the water expands and moves through capillaries to these very small air pockets and the expansive force is relieved.  Without these relief air pockets, the forces created by the expanding ice formation would rupture the concrete at its surface. This rupturing is known as scaling.

Basically, this is the theory of concrete mixes.  Quality concrete consists of a mixture of sound, durable, fine-graded, and coarse aggregate mixed together with cement, water, and air entrainment. When properly mixed, placed, and cured, the resultant concrete has strength and durability and provides the service life for which it was designed. Only by vigilant inspection can fulfillment of these requirements be ensured.

Duties and Responsibilities

The concrete control inspector is responsible for the fulfillment of all required tests and validation of all specification requirements for concrete. The Inspector cannot alter or waive any provision of the proposal, plans, or specifications. Any failure of the work or materials to conform to specifications must be corrected immediately. If necessary, production must be stopped for correction rather than permitting work that does not meet specification requirements to proceed.  The Inspector must notify the Contractor and the Engineer of such action. The Inspector's duties include verifying that approved materials are used, verifying the Job Mix Formula (JMF) is approved, performing tests as outlined in this manual, requiring adjusts of the mix when out of specification allowances, and enforcing the mixing requirements for the mixes used.

Copies of forms to be filled out or verified by the Inspector are interspersed within the text of this section and the use of the forms is described. 

Materials (499.02)

All materials to be used in the production of concrete must be tested and approved or accepted by certification prior to use.  A copy of the Laboratory report or e-mail indicating approval of material must be in hand before a material is used.  When necessary, material may be used when notification of its approval has been given by phone from the Laboratory, provided the phone approval is recorded in the project records prior to use.  When written approval is received, it is filed in the project records.  No material is used unless it is determined that it has been approved.

Portland Cement

Cement generally is shipped in bulk quantities by truck from the cement plant or terminal to the concrete plant.  The cement normally will be from a plant operating under the "Cement Certification Procedure" outlined in Supplement 1028 and will require a 1/2-gallon sample which equals to a 10-pound (4.6 kg) sample every 180 days from each ready mixed concrete plant.  The Office of Materials Management (Laboratory) or the District Test Lab typically samples Portland cement.

Normally Type I Portland cement (701.04) is used. However, the general specifications permit the use of Type IA air entraining Portland cement (701.01), Type II moderate sulfate resistant Portland cement (701.02), Type III high-early strength Portland cement (701.05), and Type I(SM) Portland blast furnace modified slag cement (701.09).

An approved air-entraining admixture is required to provide the specified air content when non-air entraining cements are used and may be required if air-entraining cement is used to obtain the proper amount of air.

Only Type I (701.04) Portland cement is the standard cement used.  There are other cement options in 701 but they may only be used when accepted within the JMF.

If high-early-strength concrete is specified, Type III must be used. 

If moisture is exposed to cement prior to mixing, it may cause the concrete to have slower setting time and reduced strength.  Therefore, cement must be stored in waterproof bins or silos.

Truck transports generally load the cement into the storage bins using compressed air, so it is important that adequate vents are placed at the top of the bins. Unless adequate vents are provided, cement must not be loaded at the same time concrete is being batched. Small or restricted vents may be inadequate and could result in inaccurate weighing of the cement at the time cement was being loaded into the bins.

Aggregate

Fine and course aggregate must be approved prior to use under the Supplement 1069 Pre-qualified Aggregate Supplier Program and meet the requirements of 703.01.  Pre-qualified aggregate suppliers and producers are listed on ODOT’s website.

Controlling the use of aggregate is the responsibility of project personnel, while the Laboratory is responsible for approving material. 

Fine Aggregate

Fine aggregate for concrete includes natural sand and sand manufactured from stone.  Natural sand is required to be used in any exposed concrete riding surface including 255, 256, 451, 452, 526, and 511(bridge deck concrete).

Fine aggregate consists of relatively small particles and does not tend to separate as much as coarse aggregate.  Therefore, segregation generally is not a problem with the fine aggregate unless extremely careless methods of handling are employed.

Coarse Aggregate

If concrete is used for 305, 451, or 452 pavement it must also comply with 703.13 which is a test for freeze-thaw resistance (D-cracking susceptibility).

Coarse aggregate is a graded material consisting of a combination of various particle sizes that require extreme care when handling to prevent the smaller particles from separating from the larger ones.  The separation that may occur during handling is known as segregation.  If aggregate is dropped from a bucket or from a belt and allowed to form a cone-shaped stockpile or if it is pushed over the edge of a stockpile, the larger aggregate particles will roll to the bottom, outside edge of the pile.  The smaller particles are less  likely to roll because of their small size and weight and remain closer to the center.  This results in a segregated stockpile.  Non-uniformity results when such material is used in the concrete mix and difficulty can be encountered in controlling the water demand, slump, and yield of the resultant concrete.

Coarse aggregate must be maintained with uniform moisture content above saturated surface dry condition.  Watering or sprinkling of aggregate may be desirable to provide concrete of uniform slump, to lower the aggregate temperature during hot weather, in addition to overcoming the possibility of a rapid slump loss.  When placing concrete during freezing weather, however, it is impractical to water a stockpile to maintain uniformity.

When sprinkling is desirable, it should be done in advance  so that the water will be distributed uniformly throughout the stockpile.  If stockpiles are large or contain aggregate having high absorption, such as slag, it may be necessary to start watering several days in advance. However, the sprinkling should be discontinued to permit excess moisture to drain off overnight.

Microsilica

Microsilica, also known as silica fume or condensed silica fume, is a pozzolanic admixture that must comply with 701.10. In its finely-divided form and in the presence of water, it will chemically react with calcium hydroxide released by the hydration of Portland cement to form compounds with cementitious properties.  This light to dark gray powdery product is the result of the reduction of high-purity quartz with coal in an electric arc furnace in the manufacture of silicon or ferrosilicon alloys.  Silica fume rises as an oxide vapor from a furnace 3,630 F (2,000 C).  It cools, condenses, and is collected in cloth bags. The condensed silica fume is then processed to remove impurities and control particle size.

Condensed silica fume particles are 100 times finer than cement particles.  The specific gravity of silica fume varies between 2.10 and 2.25 but can be as high as 2.55.  When used in concrete it will fill the void space between cement particles resulting in impermeable concrete.

Microsilica or condensed silica fume is provided in dry densified powder form and must be protected from moisture.  The microsilica normally will be from a plant operating under the "Microsilica Certification Procedure" outlined in Supplement 1045 and will require a 10-pound (4.6 kg) sample every 180 days from each ready mixed concrete plant. 

Ground Granulated Blast Furnace Slag (GGBFS)

Ground Granulated Blast Furnace Slag (GGBFS) is a material that may be allowed or required by certain specifications. It is used as a cement replacement. The GGBFS material is produced from granulated blast furnace slag granules that are ground to a consistency somewhat finer than cement. The granules are produced by tapping molten slag from an iron blast furnace and using high-pressure water to rapidly quench the material.  The granules produced have a consistency and color of sand and are composed primarily of glass.  The granules are then ground in a cement mill into a fine white powder.

The material is required to meet the ASTM C 989 Specification. This specification identifies three grades of material: Grade 80, Grade 100, and Grade 120.  Only Grades 100 and 120 are permitted under the Department's specifications.  GGBFS generally is shipped in bulk quantities by truck from the cement plant or terminal to the concrete plant.  The GGBFS normally will be from a plant operating under the "GGBF Slag Certification Procedure" outlined in Supplement 1034 and will require a 10-pound (4.6 kg) sample every 180 days from each ready mixed concrete plant. 

Concrete produced using GGBFS will have a slower strength gain in cooler temperatures than normal mixes without it.  Due to this, there are certain prohibitions for its use during cooler temperatures; GGBFS must be kept dry as with Portland cement and fly ash.  It is handled generally in the same manner as cement and fly ash.  It is normally delivered in bulk; however, for a small project, it can be provided in bags. In either case, it should be stored in a dry location.

Fly Ash

When coal is used to fire the boilers of modern power stations it is first finely ground or pulverized to the fineness of face powder before being fed into the furnace.  The burning powdered coal gives off heat to generate electricity, any coarse particles fall to the bottom of the furnace, and hot gasses given off are swept away to be exhausted up the chimneystack.  The fine particles that are in this exhaust and which are trapped before passing into the atmosphere are "fly ash." During the combustion process, the bulk of these particles assume an almost spherical shape, like microscopic ball bearings.  One of the properties of fly ash is that, in the presence of hydrating Portland cement, it behaves like cement. Fly ash reacts with calcium hydroxide to form compounds possessing cementitious properties.

Two classes of fly ash are allowed for concrete in 701.13.  The two classes are Class F and Class C.  Class F fly ash is produced from burning anthracite or bituminous coal.  Class C fly ash is produced from burning lignite or sub-bituminous coal.  Class F fly ash is the type normally found in Ohio.  However, Class C fly ash is also becoming available to concrete producers now. Class C fly ash has some cementitious properties by itself while Class F does not.

Fly ash used in Department work must meet the requirements of ASTM C 618 except the maximum loss on ignition (LOI) must not exceed 3 percent.  The LOI is a measurement of the carbon content or unburned coal in the fly ash.  In order to maintain air entrainment at a particular level (in concrete containing fly ash), the fly ash must have a low LOI. The ASTM specification allows a higher LOI than our specifications.  ODOT specifications require the lower LOI to minimize problems entraining air in the concrete.

Fly ash will normally be shipped in bulk quantities by truck from the power station to the concrete plant.  Fly ash, like cement, has a certification process.  This process is described in Supplement 1026, “Fly Ash Certification”.  Certified fly ash requires a half-gallon (2L) sample every 180 days from each ready mixed concrete plant.  Non-certified fly ash shall be sampled every 100 tons (91 metric tons) and be approved prior to use.

Concrete containing fly ash is permitted only between April 1 and October 15 due to slow strength gain in cold temperatures.

Bulk fly ash must be stored in waterproof bins prior to use.  Normally fly ash is handled in the same manner as cement.  Only one source of fly ash is permitted in any one structure unless otherwise approved by the Director.

Air-Entraining Admixture

Air-entraining admixtures are used to entrain the proper amount of air in concrete for freeze thaw durability.  These admixtures must comply with 705.10 and conform to Supplement 1001 Approval and Testing of Air Entraining Agents and Chemical Admixtures for Concrete.  The list of approved air entraining admixtures for Department use can be obtained from the SiteManager or from the Qualified Products List (QPL) on the ODOT website.

Air-entraining admixtures are randomly sampled at the concrete plant.  The Laboratory generally takes these samples.

Chemical Admixture for Concrete

Approved set-retarding or water-reducing and set retarding admixtures are permitted in order to increase the workability of the concrete and to extend the time of discharge from 60 to 90 minutes.  These admixtures are permitted and often required for superstructure concrete.

Should the Contractor propose to use calcium chloride as an accelerator in the concrete, it must be determined if such use is permitted by specification, plan, or proposal note.  If not, the Contractor must request permission of the Director, in writing, to use such admixtures. 

Admixtures used under 499 must meet the requirements of 705.12 that specify that they meet ASTM C 494, except that the relative durability factor shall be 90.  These admixtures must comply with Supplement 1001 Approval and Testing of Air Entraining Agents and Chemical Admixtures for Concrete.

The list of approved admixtures for Department use can be obtained from the SiteManager or from the Qualified Products List (QPL) on the ODOT website.

Chemical admixtures as defined by ASTM C 494 include:

·         TYPE A - Water reducing

·         TYPE B - Retarding

·         TYPE C - Accelerating

·         TYPE D - Water reducing and retarding

·         TYPE E - Water reducing and accelerating

·         TYPE F - Water reducing, high range

·         TYPE G - Water reducing high range and retarding

Generally, liquid admixtures are shipped and stored at the plant in drums or tanks.  The admixture material is withdrawn directly from the drum and dispensed into the concrete.  Drums or tanks containing liquid admixtures should be agitated before being used.  In the absence of a dispenser, the admixture must be introduced accurately into the mix by hand.   Drums or tanks for storage of liquid admixtures should be watertight and protected from freezing.

At ready mix plants producing large volumes of concrete, the air entraining and other chemical admixtures are delivered in bulk quantity by tank trucks.  These bulk admixtures are pumped into storage tanks at the plant and then dispersed into concrete batches.

Water

Water that is suitable for drinking is satisfactory for use in concrete (potable water).  Water must be free of sewage, oil, acid, strong alkalis, vegetable matter, clay, and loam.  Water from such sources should be avoided. Whenever there is a reason to suspect that water proposed for use in concrete is not suitable, it must be tested and approved before it may be used.  A one-gallon (3.8L) sample in a non-corrosive container (plastic or glass) must be transmitted to the Laboratory with a TE-31 Sample Data form for comparative testing.

Wash water used to clean out ready mixed concrete must be discharged from the mixing drum prior to recharging any truck with new materials.

An adequate supply of water must be available at the concrete plant to provide for mixing and stockpile watering for uninterrupted production.  Adequate storage tanks kept filled or a connection to a water supply system usually will provide a sufficient supply.

Proportioning (499.03 and 499.04)

Concrete is to be proportioned (mixed) and controlled as per the requirements of 499.03 and 499.04.  Slump, air content, and yield is given in Tables 499.03-1 and 499.03. Water/cement ratio is limited by the specific Job Mix Formula (JMF).  The JMF also provide the aggregate weights, and cement content for each concrete mix.

Slump should be maintained within the nominal slump range shown in table 499.03-3 for the mix design.  The slump of concrete delivered to a project may be increased by the addition of water only if the maximum water cement ratio (or water to cementitious ratio) is not exceeded. 

Do not allow the use of any concrete that exceeds the maximum slump.  An occasional load of concrete with a slump in excess of the nominal slump, but below the maximum limit shown in the table, may be incorporated into the work provided that an immediate adjustment is made to reduce the slump.

In some cases, it will not be practical to use this maximum slump due to a required cross-slope or a super-elevation.

Concrete Classes (499.03)

The Department uses contractor designed mixes that are found by looking up the Contractor’s submitted JMF in SiteManager.  Table 499.03–1 shows basic classes of concrete mix designs.

TABLE 499.03-1

Quantities per Cubic Yard

Provide Concrete with 6±2% Air Content

Class

Design Strength

psi (MPa)

Permeability [1]

Maximum (Coulombs)

Cementitious Content [2]

Minimum.

 lbs (kg)

Aggregate

Requirements

QC 1

4,000 (28.0) at 28 days

2,000

520 (236)

Well-Graded

QC 2

4,500 (31.0) at 28 days

1,500

520 (236)

Well-Graded

QC 3

Special

As per plan

1,500

or as per plan

520 (236)

or as per plan

Well-Graded

QC 4 Mass Concrete

As per plan [3]

2,000

or as per plan

470 (213) [4] [5]

or as per plan

Well-Graded

QC MS [7]

See Supplement 1126

N/A

800 [7] (475)

1 inch nominal maximum size

QC FS [7]

See Supplement 1126

N/A

900 [7] (534)

1 inch nominal maximum size

QC Misc [6]

4,000 (28.0) at 28 days

N/A

550 (250)

1 inch nominal maximum size

[1]  AASHTO T277 Modified

[2]  Cementitious Content includes cement and pozzolan materials, denoted as Cm

[3] Strength for Mass Concrete (QC 4) may  be tested at either 28 or 56 days.

[4] Do not use Type III cement or accelerating admixtures in mass concrete.

[5] The maximum fly ash or GGBF slag content may be increased up to 50%.

[6] For QC Misc mixes only –Water/Cementitious ratio limited to 0.50 maximum

[7] Cement Only – No pozzolan materials

The class of concrete is generally called out in the specification of the item of work in which the concrete is to be used.  The proportioning of these classes is based on developing an average compressive strength at 28 days as shown in the table.

Additional Classes of Concrete for Rigid Replacement

The Specifications provide for two other classes of concrete (Class QC FS and Class QC MS) normally used for full-depth rigid pavement removal and rigid replacement (Item 255).  These concretes are intended for high-early-strength; therefore, the previously described proportioning options do not apply to these classes of concrete.

It should be noted that Class QC FS or QC MS concrete is for use in full-depth rigid pavement removal and rigid replacement (Item 255).  It allows No. 57 and No. 67 size coarse aggregate that does not have to be tested in accordance with 703.13 (testing for d-cracking susceptibility).  If it is necessary to use either Class QC FS or QC MS concrete in 451 or 452, and JMF size coarse aggregate is to be used, the aggregate must comply with 703.13.

When either FS or MS concrete is used, ensure the JMF for the mix design proposed by the Contractor or the ready mixed concrete company has been accepted.  The specific gravity of all aggregates must be known to figure the absolute volumes at all component materials to ensure that the concrete yields a cubic meter (cubic yard) of concrete.  Just like any concrete, the air, slump, and yield must be controlled, and the water-cement ratio must not be exceeded.

Class QC FS Concrete (Fast Setting Concrete)

Class QC FS concrete must be proportioned with a minimum 900 pounds per cubic yard (534 kilograms per cubic meter) and a maximum water/cement ratio of the accepted JMF.  Accepted JMF’s will have the original time to strength curves available.  Not all mixes will achieve 400 psi (2.76 MPa) in 4 hours.  Available aggregates and weather conditions in the field will affect the results. This concrete may be opened to traffic after 4 hours if test beams have attained a modulus of rupture of 400 psi (2.76 MPa).  This concrete must have either a Type B or a Type D admixture (a set retarder) added at the plant.  Immediately prior to placing the concrete, calcium chloride (an accelerator) must be added and mixed at the project site.

Calcium chloride with 94 to 97 percent purity is limited to 1.6 percent by weight of cement, and calcium chloride with 77 to 80 percent purity is limited to 2.0 percent by weight of cement. If calcium chloride is added in liquid form, the water in the solution must be considered to be part of the mixing water and an appropriate adjustment must be made to not exceed the JMF water cement ratio.

In lieu of calcium chloride, any other approved accelerating admixture is permitted if the product was used in the accepted JMF. 

After curing compound is applied, the concrete is to be covered with polyethylene sheeting and further covered with insulation board that has been wrapped with plastic.  The intent is to keep the heat in the concrete so that the concrete can gain strength rapidly.  During warm weather, 400 psi (2.76 MPa) is normally attained in 5-1/2 hours.

Class QC MS Concrete (Moderate Setting Concrete)

This class is a moderate setting Portland cement concrete for accelerated strength development.  Class QC MS concrete is to consist of a minimum of 800 pounds of cement per cubic yard (475 kilograms of cement per cubic meter) and the maximum water cement ratio is defined in the accepted JMF. This mix may be opened to traffic after 24 hours provided test beams have attained a modulus of rupture of 400 psi (2.76 MPa).

Basics Concepts used in Concrete Quality Control

Volume

There are three types of volumes used in concrete quality control:

1.        solid (absolute)

2.        loose (bulk)

3.        liquid volume

Solid and loose volume is normally defined by the number of cubical units of enclosed or occupied space.  Normally one speaks of the number of cubic feet or cubic yards (cubic meters) of concrete.  Liquid volume is designated by gallons (liters) for measurement of water and ounces (milliliters) for measurement of admixture dosage rates. 

Unit Weight

Unit Weight is an important volume relationship used in concrete quality control.  Unit weight is defined as the ratio of the weight of a material in pounds (kilograms) to the space or volume that it occupies in cubic feet (cubic meters).  The unit weight of any material is calculated by Equation 499.1:

Equation 499.1 – Material Unit Weight

Concrete is sold by volume, but is batched by weight.  The Inspector determines the unit weight of the concrete and uses it to calculate the yield of the batch.  The yield is the actual number of cubic feet (cubic meters) or volume of concrete that a batch or load produces.  Equation 499.2 shows how yield is calculated:

Equation 499.2 – Batch Yield

Specific Gravity

Specific gravity values of aggregates are used to calculate aggregate weights used in concrete mix design.  Where the actual specific gravity of an aggregate varies by more than ±0.02 from those listed in accepted JMF, the mix design weights shown in the JMF must be adjusted.  This section shows how to make those adjustments. 

The specific gravity of any material is the ratio of the weight in pounds (kilograms) of the material to the weight of an equal volume of water.  Another way to say this is that it tells how much heavier or lighter a given material is than water.  Water has a specific gravity of 1.00.  The unit weight of water is 62.4 pounds per cubic feet, lb/ft³ (1,000 kilograms per cubic meter, kg/m³).

The concrete proportion section of SiteManager for the JMF give the quantities of all materials to be used in each cubic yard (cubic meter) of concrete, depending on what class of concrete and the type of aggregate is used.  The aggregate weights given in the tables are the saturated surface dry (SSD) design weights.

See example of SiteManager JMF info below.

If the specific gravities of the proposed aggregate materials for use on a project vary by more than 0.02 on the approved aggregate list from the specific gravities shown in the JMF, the Engineer should require adjustment of the table weights as specified in the JMF.  This is done by dividing the SSD design table weight by the design specific gravity (from the JMF) and multiplying this by the actual specific gravity that is going to be used on the project.  Equation 499.3 shows this calculation:

Equation 499.3 – Adjusted SSD Design Weight

Where:

= Design Weight (SSD) from the Job Mix Formula (JMF)

  DSG      = Design Specific Gravity from the JMF

 ASG       = Actual SSD specific gravity to be used on the project

Adjusted  =      Design Weight (SSD) adjusted for the actual aggregate specific gravity

Example:

Class QC 2 concrete, using natural sand and limestone coarse aggregate, is to be used on a project.  The specific gravity of the fine aggregate is 2.66 and there is the specific gravity of 2.68 for the coarse aggregate.  Determine the adjusted SSD design weights of fine and coarse aggregate based on these specific gravities.

The SSD design weights and design specific gravities for Class QC 2 concrete in JMF for natural sand and limestone coarse aggregate are:

Aggregate Type

Design Weight  (SSD)

Design Specific  Gravity

Fine Aggregate (Nat. Sand)

1,240 lbs

2.62

Coarse

Aggregate (Limestone)

1,510 lbs

2.65

The SSD design weights adjusted for the specific gravities are calculated as follows:

Fine Aggregate Adjusted     =   

Coarse Aggregate Adjusted    = 

These adjusted aggregate weights () would be further adjusted for moisture contained in them at the time of use instead of the table weights.

Absolute Volume

The material proportions for concrete mixtures JMF given in pounds (Kg).  Any adjustments to the aggregate proportions must be done using absolute volumes.  For example, the yield of a batch of concrete is required to be accurate within a tolerance of ± 1 percent at the target (design) air content and slump.  If an over- or under-yield is experienced adjustments in the batch weights need to be made.  The Inspector should notify the Engineer and Contractor of the yield issue.  An adjustment to the proportions needs to be made if the Contractor wants the mix to stay within tolerance.  Based on the yield calculated by the Inspector or Contractor, it will be necessary to calculate the weight in pounds  (kilograms) of aggregate required for a certain amount of yield correction in cubic feet (cubic meters).  Adjustments to correct yield are to be based on the absolute volume.

When the specific gravity of any material is known, the absolute volume of any weight of that material can be calculated as shown in Equations 499.4 and 499.5:

Equation 499.4 – Absolute Volume

Equation 499.5 – Absolute Volume (metric)

Example:

The absolute volume of 94 lbs (42.6 kg) of Type 1 cement that has a specific gravity of 3.15 is:

This calculation shows that 94 lbs (42.6 kg) of cement, which represents 1 cubic foot of loose volume, has an absolute volume of 0.48 ft³ (0.0135 m³).

Yield Adjustment using Absolute Volume

To make a yield adjustment, a volume of over-yield or under-yield is first determined.  This absolute volume must be converted to a weight of material.  An absolute volume of any material can be converted to a weight of that material by using Equations 499.6 and 499.7:

Equation 499.6 – Weight from Absolute Volume

Where:

                                AV = absolute volume of the material (ft³)

                                SG = specific gravity of the material

                                62.4 = lbs/ft³

Equation 499.7 – Weight from Absolute Volume (metric)

Where:

                AV = absolute volume (m³)

                SG = specific gravity

                1,000 = kg/m³

Example:

Calculate how many pounds (kg) of a coarse aggregate, with a specific gravity of 2.66, would be required to adjust an under-yield of 0.64 ft³ (0.018 m³).  The calculation is as follows:

                Weight (lbs) = (0.64 ft³) x (2.66) x (62.4 lbs/ft³) = 106.2 lbs

                (Weight (kg) = (0.018 m³) x (2.66) x (1,000 kg/m³) = 47.88 kg)

Thus, 106 lbs per cubic yard (48 kg per cubic meter) of coarse aggregate, with a specific gravity of 2.66, would have to be added to correct the above under-yield volume of 0.64 ft³ (0.018 m³).

While the example shows only a coarse aggregate correction, a correct over- or under-yield would have all aggregate proportions corrected to make up the yield different.

If the aggregate for a mix was:

40% No. 57 stone

20% No. 8 stone

40% natural sand

You would determine the percentage for the under-yield (above):

40%/100 x .64 = .26 ft³           No. 57 stone

20%/100 x .64 = .14 ft³           No. 8 stone

40%/100 x .64 = .26 ft³           natural sand

Then, calculate (using the above) formal and the specific gravity for each to determine the amount of materials to be added for each aggregate type.

Moisture Correction

Aggregate can be in one of four moisture conditions:

1.        Oven-dry aggregates are heated until they are completely dry.  There is no moisture within the aggregate particles or on the surface of the particles.

2.        Air-dry aggregate is dry on the surface, but still contains some water within the aggregate particles.  Air-dry aggregate will absorb a small amount of mixing water if used in concrete.  Aggregate in this condition requires adjustments to the design weights and adjustment of the batch water.

3.        Saturated surface dry (SSD) aggregate looks damp, but it contains no free water on the surface. The aggregate particles have completely absorbed all the water possible and do not contribute water to the batch.  The concrete tables in the JMF give SSD weights of coarse and fine aggregate, but aggregate in this condition rarely exists in aggregate stockpiles.

4.        Wet (damp) aggregate has water on the particle surface and shows  water sheen.  The aggregate particles have absorbed all the water they can and will contribute water to the concrete mix. Aggregate in this condition requires adjustments to the design weights and adjustment of the batch water.

In the field, aggregate used in concrete will be in a wet (damp) condition or air-dry condition.  Aggregate in the SSD or oven-dry conditions is used by contractors and inspectors to determine moisture correction factors for use in adjusting the SSD design weights. 

Before concrete can be batched, the concrete mix SSD design weights shown in the JMF must be converted to batch weights.  This is done by adjusting the design SSD weight of each aggregate and adjusting the amount of batch water to compensate for the moisture in the aggregates.  If all aggregates at the concrete plant were in the SSD condition, the weights given in the concrete tables could just be weighed up and incorporated into the concrete batch and no adjustments to the water would be necessary.  Seldom, if ever, will aggregate in the field be found in the SSD condition. 

It is necessary to determine the amount of total moisture in all aggregate in order to determine the weight of wet (damp) or air-dry aggregate necessary to give the correct weight of SSD aggregate. This total moisture content is used in the determination of the water-cement ratio.  For example, if an aggregate is determined to contain 5 percent total moisture, then each 105 pounds (kilograms) of that aggregate actually consists of 100 pounds (kilograms) of aggregate and 5 pounds (kilograms) of water.  In order to obtain 100 pounds (kilograms) of aggregate by dry weight, it is necessary to take into account the water that will be weighed along with the aggregate.

Total Moisture Correction Factor

The Total Moisture Correction Factor (TMCF) is a term that is useful in determining the batch weights from SSD design weights (that have been corrected for specific gravity).  The TMCF can be determined by a moisture test.  To determine the TMCF use Equation 499.8.

Equation 499.8 – Total Moisture Correction Factor (TMCF)

Where:

                TMCF = Total Moisture Correction Factor

                WW= Wet weight of the sample

                ADW = Air Dry Weight of the sample

                ODW = Oven Dry Weight of the sample

If the total moisture content (in percent) has been determined by an aggregate moisture test, use Equation 499.9 to calculate the TMCF:

Equation 499.9 – Total Moisture Correction Factor (TMCF)

The total moisture percent is changed to a decimal (by dividing it by 100) and then added to 1.0000 to get the TMCF.  For example, if the total moisture in an aggregate sample, after testing, is determined to be 5.8 percent, then the TMCF is determined as follows:

Absorbed Moisture Correction Factor

Another factor that is useful to determine the batch weights from SSD weights (that have been corrected for specific gravity) is the Absorbed Moisture Correction Factor (AMCF).  This factor can be determined by a test.  It is defined as follows:

Equation 499.10 – Absorbed Moisture Correction Factor (AMCF)

Where:

                AMCF= Absorbed Moisture Correction Factor

                SSDW= Saturated Surface Dry Weight of the sample

                ODW= Oven Dry Weight of the sample

The percent of absorption of the fine aggregate and coarse aggregate is obtained from the aggregate reports furnished by the Laboratory.  The percent of absorption represents the amount of water, expressed as a percentage of its own dry weight, which an aggregate will absorb.  The water that is absorbed by aggregate is not available as mixing water in the concrete.  Adjustments must be made in the amount of total allowable mixing water to compensate for the free water on the aggregate surface. 

The percent absorption of any aggregate can be found on the Office of Materials Management website under Materials Information, Aggregate, and Specific Gravities List. 

The Materials Management website is listed below:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Materials/Pages/default.aspx

The percent absorption is on the far right column of this list.  The sources are listed in alphabetical order.  Once the percent absorption of any aggregate is known, the AMCF can be determined by Equation 499.11:

Equation 499.11 – AMCF

The percent absorption of the aggregate is changed to a decimal (by dividing the percentage by 100) and then it is added to 1.0000 to get the AMCF.  For example, if the percent absorption for a coarse aggregate is 2.22 % then the AMCF is determined as follows:

Free Moisture Correction Factor

The Free Moisture Correction Factor (FMCF) can be calculated once the TMCF and the AMCF are determined by using Equation 499.12:

 Equation 499.12 – FMCF

Where:

                FMCF= Free Moisture Correction Factor

                TMCF= Total Moisture Correction Factor

                AMCF=Absorbed Moisture Correction Factor

The FMCF is used to adjust the corrected SSD design weights of the coarse aggregate and the fine aggregate from the concrete tables in the JMF’s batch weights that are used to produce a batch of concrete.  The batch weight for any aggregate is determined by either Equation 499.13 or 499.14:

Equation 499.13 – Batch Weight method 1

Equation 499.14 – Batch Weight method 2

Where:

= Design Weight (SSD) from the concrete table, adjusted for the specific gravity

                FMCF=   Free Moisture Correction Factor

                TMCF=   Total Moisture Correction Factor

                AMCF=  Absorbed Moisture Correction Factor

Example:

Assume that the following are the design weights SSD adjusted for specific gravity for a cubic yard of Class QC 1 concrete:

                                Cement                                     600 lbs

                                SSD Fine Aggregate               1,160 lbs

                                SSD Coarse Aggregate           1,735 lbs

                                Maximum Water                       300 lbs

                                Total Design Weight               3,795 lbs

Prior to concrete placement, the total moisture contents of the fine and coarse aggregates are determined.  The fine aggregate has total moisture of 4.95 percent and the coarse aggregate has total moisture content of 3.25 percent.  The absorption of the fine aggregate is 2.85 percent and the absorption of the coarse aggregate is 2.1 percent.  Determine the batch weights using the above moisture data.

First, determine the TMCF and the AMCF for each aggregate type using Equations 499.9 and 499.11:

Fine Aggregate TMCF

(Equation 499.9)

Fine Aggregate AMCF

(Equation 499.11)

Coarse Aggregate TMCF

(Equation 499.9)

Coarse Aggregate AMCF

(Equation 499.11)

Next, use Equation 499.14 to determine the fine and coarse aggregate batch weight:

Fine Aggregate Batch Weight

(Equation 499.14)

Coarse Aggregate Batch Weight

(Equation 499.14)

Next, determine the amount of water added to the mix by each aggregate.  To determine this weight, subtract the SSD design weight from the batch weight determined above:

Water in Fine aggregate           = 1,184 – 1,160       = 24 lbs

Water in Coarse aggregate       = 1,753 –1,735        = 18 lbs

Next, the mix design weight of water must be adjusted to determine the batch weight of water.  In this example, the fine aggregate and coarse aggregate would both contribute water (24 lbs and 18 lbs respectively) to the mix.  The batch weight of water is calculated by subtracting the amount of water added by the aggregate from the design water weight as follows:

Water Batch weight = 300 lbs - 24 lbs – 18 lbs = 258 lbs

Once the batch weights of all the ingredients have been determined, they should add up to the same as the original design weights.  This is a good check to ensure that no errors were made in the calculations.  The batch weights for a cubic yard of concrete based on the total moistures and the aggregate absorptions given in this example are:

Cement

600 lbs

SSD Fine Aggregate

1,184 lbs

SSD Coarse Aggregate 1

1,753 lbs

Maximum Water

258 lbs

Total Batch Weight

3,795 lbs

Since the total batch weight equals the original adjusted SSD design weights in this example, the mix has been adjusted properly for the moisture in the aggregates.  Even though the maximum water value in the total batch weight (258 lbs) is different than the original design weight of water (300 lbs), the net water was not changed.  The free moisture in the aggregates will contribute 42 lbs to the mixing water.  In this example, the w/c ratio was kept the same as the original design.

Job Control Tests

The concrete control Inspector must perform various field tests to determine whether a concrete mixture is within specifications for slump, air content, and yield.  In QC/QA, these tests have specific frequency.  Yield is not an acceptance test but may be used to determine additional information where there are problems.  The Inspector is there to verify the Department receives product which meets the specifications.  Moisture testing also has to be performed for use in the concrete mix design control. 

Specification 499.04 requires that concrete quality control QC tests are performed.  Tests for total air content and slump may be made at ready mix and central mix plants for control purposes.  These tests are desirable to detect loads that will not conform to specification requirements before they leave the plant.  Any variances to the JMF should be reported by the plant to the Contractor so that necessary adjustments can be made in the following batches.  This type of testing determines quality and is the responsibility of the Contractor. When concrete is produced in accordance with a QC/QA specifications (Items 451, 452, 511), the formal Contractor additional quality control requirements at the placement site are required.

Department testing is always considered quality assurance (QA) to verify that the Contractor provided product meets specifications. 

Unless otherwise directed by the Engineer, perform any QA tests for pavement on plastic concrete samples taken from the concrete after it has been placed on the base.  In the event excess slump is encountered, it may be desirable to visually observe the consistency (slump) of the concrete in the bucket or trucks before deposition to avoid the necessity of costly removal after it is placed.

Perform QA tests for structural concrete at the site at the time the concrete is being placed.  Normally, concrete may be obtained directly from the hauling units for testing.  However, when concrete is transferred from the hauling units to the point of use by means of conveyors or by pumping, the amount of slump and air may change slightly. 

Perform testing at the required frequency of the specification or at a higher frequency if problems are noted.  Do not perform the QC testing, but provide QA test results to the Contractor so the Contractor can make necessary corrections.

There may be occasions where it is not practical to test concrete samples at the point of placement since this would interfere with placing operations such as for a pier cap.  Usually there is not adequate space for testing.  In this situation, the sample could be taken from the point of placement and tested at a different location.  Correlation of test data between point of test and placement may be necessary to ensure specification material is being placed.  Tests could be conducted on concrete obtained from the hauling units and allowance made for a change in slump and air as determined by the comparative tests at the point of placement.

Slump, yield, and entrained air tests are made by the concrete control Inspector.  In addition, it is the Inspector's duty to make required test cylinders and beams.  Any adjustment of batch weights that may be necessary because of the routine job control tests must be relayed to the concrete plant for immediate use.  The concrete Inspector must be familiar with the tests being conducted and should occasionally review the test procedures to ensure that all tests are properly conducted.

Representative Concrete Samples

When obtaining a sample from dump trucks, side dump hauling units, or other types of hauling units that do not discharge by a chute, the contents are first discharged or spread on the base.  Samples are then taken from several different locations within the load.

When sampling from truck mixers, truck agitators, end dumps, or other units discharging by a chute, the sample is obtained at three or more regular intervals throughout the discharge of the entire batch.  Do not sample at the beginning or end of discharge.  Sampling is done by repeatedly passing a receptacle through the entire discharge stream, or by diverting the stream so that it discharges into a container.  The rate of discharge must be regulated by the rate of revolution of the drum, and not by the size of the gate opening.

The sample consists of not less than 1 cubic foot (0.03 cubic meters) when it is used for cylinders and not less than 1 cubic foot (0.03 cubic meters) per beam.  Smaller samples may be permitted for routine air content and slump test.

The sample is carried to the place where cylinders and beams are to be molded or where the test is to be made.  The sample is then remixed with a shovel just enough to ensure uniformity.  The sample must be protected from sunlight and wind during the period between sampling and testing.  The test must be conducted immediately so that the time between sampling and test completion is held to a minimum.

Moisture Testing

This test is the responsibility of the Contractor under QC/QA specification or the concrete producer when not under QC/QA (499.04)   a moisture test is made for each aggregate size to be used. These tests must be made just prior to the start of concrete production and are used to adjust the batch weights and to determine the water-cement ratio. Therefore, moisture tests are required at the start of production, daily for all major concrete placements, and anytime a sizeable change occurs in the moisture content of the stockpiles. Moisture tests by concrete suppliers are often performed using calibrated probes in their stockpiles.  These are acceptable if the results are accurate. Those results can and should be the used by the Contractor or supplier to adjust SSD mixes for local moisture content.

Space is provided on Form TE-45 for documenting the moisture content test on each aggregate used.

Any appreciable change in the amount of water added at the mixer must be investigated, additional moisture tests made, and if necessary, the batch weights adjusted accordingly.  Concrete suppliers use of stockpile probes can help with the variations as they make readings throughout the mix process

Following a heavy rainfall, periodic moisture tests are necessary until the moisture content becomes uniform.  Slight variations in the mixing water requirements do not require a moisture test and adjustment. However, it may become necessary to alter the methods of watering, stocking, and withdrawing the aggregate to avoid fluctuations in water.

The total percent moisture is determined by using Equation 499.15:

Equation 499.15 – Total Percent Moisture

Where:

NWW = Net Wet Weight of the aggregate sample

NDW= Net Dry Weight of the aggregate sample

To determine the percentage of moisture or water in fine or coarse aggregate, place a representative sample of 5 to 10 pounds (3 to 5 kg) in a pan that has been weighed empty and determine the wet weight of aggregate and pan.  Place pan and aggregate over a fire, or in an oven, and dry to constant weight.  Subtract the weight of the empty pan from both the wet and dry weights obtained. The results will be the net wet weight and the net dry weight.  Next, subtract the net dry weight from the net wet weight, which results in the moisture content (weight of water) in the wet aggregate sample in pounds (kilograms).  Divide the moisture content by the net dry weight and multiply by 100 percent to obtain the percent moisture in the sample.

Example:

Assume that the following weights are obtained for a sample of aggregate:

Empty Pan Weight                                  = 1.22 lb (0.553 kg)

Weight of Wet Aggregate + Pan             = 8.68 lb (3.937 kg)

Weight Dry Aggregate + Pan                  = 8.44 lb (3.828 kg)

The calculations involved to determine the moisture content in the sample are:

English calculation

A.            Tare Weight of Pan = 1.22 lbs.

B.            Wet Aggregate + Pan Weight  = 8.68 lbs.

C.            B - A = Wet Aggregate Weight = 8.68 - 1.22 = 7.46 lbs.

D.            Dry Aggregate + Pan Weight  = 8.44 lbs.

E.             D – A = Dry Aggregate Weight = 8.44 – 1.22 = 7.22 lbs.

F.             C – E = Weight of Water         = 7.46 – 7.22 = 0.24 lbs.

G.            (FE) x 100%   = (0.24 ÷ 7.22) x 100% = 3.3% moisture

Metric calculation

A.            Tare Weight of Pan                 = 0.553 kg

B.            Wet Aggregate + Pan Weight  = 3.937 kg

C.            B - A = Wet Aggregate Weight = 3.937 – 0.553 = 3.384 kg

D.            Dry Aggregate + Pan Weight  = 3.828 kg

E.             D – A = Dry Aggregate Weight = 3.828 – 0.553 = 3.275 kg

F.             C – E = Weight of Water = 3.384 – 3.275 = 0.109 kg

G.            (FE) x 100%   = (0.109 ÷ 3.275) x 100% = 3.3 % moisture

Space is available on the TE-45 form for documenting the moisture content of the aggregate used.

Control of Mixing Water

Moisture testing of the aggregate used in the concrete mix design allows the calculation of the total amount of mixing water that can be used per cubic yard of concrete.  This mixing water limit should not be exceeded for the batch of concrete.

The field adjustment of slump to workable limits can be obtained by added water (up to the mixing water limit) only if the maximum water/cement ratio is not exceeded and the air content is within specification.  The Contractor and/or the Supplier assume the responsibility and financial loss for concrete that is rejected because it is outside the specification limits.  Therefore, the Contractor/Supplier should have the right to adjust the amount of mixing water. 

All approved JMF concrete mixes maximum water-cementitious (w/cm) ratios are limited by the accepted JMF:

1.        The w/cm ratio is a ratio of the weight of water to the weight of cementitious materials in a batch of concrete.

For the Department’s work, cementitious materials include cement, fly ash, ground granulated blast furnace slag (GGBFS), and micro silica.  The maximum w/cm ratio and maximum w/cm ratio are expressed mathematically by Equation 499.16:

Equation 499.16 – Maximum w/cm Ratio

The maximum w/cm ratios are used by the Inspector to determine the maximum allowable water in a concrete batch.  The concrete tables give the weight of cement and cementitious materials and the maximum allowable w/cm ratio for a cubic yard (cubic meter) of concrete.  The maximum allowable weight of water can be determined for any of the concrete mixes by using 499.17:

Equation 499.17 – Maximum Allowable Water Method 2

Where:

MAWW= Maximum Allowable Water Weight

Max. w/cm Ratio = Maximum water/cementitious ratio given in the concrete JMF

CMW = Cementitious Material Weight specified in the JMF

Once the maximum allowable water weight per cubic yard (cubic meter) is determined for a certain class of concrete, it is adjusted based on the moisture contained in each aggregate at the time of use and the moisture that each aggregate will absorb.  The batch weight of water is determined by multiplying the adjusted water weight per cubic yard (cubic meter) by the number of cubic yards (cubic meters) in the batch.

The Inspector must recognize the Contractor’s/Supplier’s right to make a change in water to prevent the possibility of having concrete rejected for excessive slump.  Inspectors are still required to record all adjustments of mixing water and to control slump and yield.  If water is added to the concrete truck at the project site, the amount must be recorded and added to the total batch weight and used in the calculation of the w/cm ratio to ensure that they are not exceeded.

The Contractor/Supplier does not have the right to adjust the water requirements without informing the Inspector.  The Inspector must know when a change is made and the amount of change in order to control and enforce the specification requirements.  Inspectors are encouraged to cooperate with the Contractor to effectively control the mixing water to provide concrete of uniform slump.

The amount of water to be added to the mix to produce concrete of the proper slump cannot be determined accurately.  Therefore, it is necessary to rely on past experience with the materials being used to estimate the amount of water to use at the start of concrete placements.

CAUTION: Additional water may be added if the estimated quantity of water produces low slump concrete, but excess water cannot be removed if the slump is in excess of maximum allowed.  Estimating water should be on the conservative side unless relying on recent experience.  When the Inspector is not familiar with the materials being used, it is good practice to choose an amount of water about 5 gallons per cubic yard (25 liters per cubic meter) less than the estimated net mixing water.

Example:

Determine the maximum allowable water content for an 8-yd³ load of Class QC 1 with the following one cubic yard design weights:

                                Cement                    385 lbs

                                GGBFS                   165 lbs

                                Fine Aggregate        1,310 lbs

                                Coarse Aggregate    1,670 lbs

                                Max. w/cm ratio      0.50

First, determine the maximum allowable water per cubic yard by use of Equation 499.17:

Since 1 gallon of water weighs 8.32 lbs, the maximum allowable water per cubic yard can be calculated as follows:

                Gallons of Water = = 33 gallons

 Next, to determine the maximum allowable water for the 8-yd³ batch, multiply the one yd³ allowable water by the size of the batch:

(275 lbs/yds³) x (8 yds³ /batch) = 2,200 lbs

                or

(33 gallons /yd³) x (8 yds³ /batch) = 264 gallons

Therefore, the maximum allowable water is 2,200 lbs or 264 gallons for the 8-yd³ batch.  This 2,200 lbs (or 264 gallons) is the maximum allowable water; that is, the amount of water that would be adjusted depending on the moisture contained in the aggregates used in the concrete.

Slump

Slump is a measure of the workability of the concrete and nominal and maximum slump values are given in 499.03.  It is measured by a standard test in accordance with ASTM C 143.  This test is done at the point of placement. 

Slump is controlled by the amount of water that is batched into the concrete.  Slump is increased as water is added to a batch of concrete.  There are chemical admixtures (Type F and G) that can increase the slump chemically, without the addition of extra water.

The specifications in Section 499.04 require that the saturated surface dry (SSD) aggregate weights in the concrete tables be corrected to compensate for the moisture contained in each aggregate at the time of use.  The amount of free water in the aggregate contributes to slump and to the water-cementitious ratio.

Table 499.03-3 Concrete Slump (below) shows the nominal slump and maximum slump allowed for certain items of work.  Note that the nominal slump for any of the listed work items can be increased to 6 inch (150 mm) if a high-range water-reducing (superplasticizing) admixture is used in the concrete.  The maximum slump may be increased to 7 inches (180 mm) if high-range water-reducing (superplasticizing) admixture is used.

Table 499.03-3 Concrete Slump

Type of Work

Nominal Slump

inch (mm)[1]

Maximum Slump

inch (mm)[2]

Concrete pavement (305, 451, 452, 615)

1 to 3 (25 to 75)

4 (100)

Structural Concrete (511, 610, 622)

1 to 4 (25 to 100)

5 (125)

Superstructure concrete (511, 526)

2 to 4 (50 to 100)

4 (100)

Non-reinforced concrete (601, 602, 608, 609, 611, 622)

1 to 4 (25 to 100)

5 (125)

[1]  This nominal slump may be increased to 6 inches (150 mm), provided the increase in slump is achieved by adding a chemical admixture conforming to the requirements of 705.12, Type F or G.

[2]  This maximum slump may be increased to 7 inches (180 mm), provided the increase in slump is achieved by adding a chemical admixture conforming to the requirements of 705.12, Type F or G.

Slump Test Requirements

This test is the responsibility of the Department except for work under a QC/QA specification, when it is that of the Contractor.  A slump test using the slump cone will be made each time a set of cylinders is cast for structures or a set of beams is cast for pavements.  Further tests are required as needed to maintain control of the slump within the limits specified.

Slump requirements apply at the point of use; therefore, slump must be determined at the work site on concrete being placed in the forms.  When concrete has to be conveyed by any means (by a concrete pump, concrete conveyor, or bucket) from the hauling units to the forms where it will be incorporated into the work, the slump should be determined from concrete obtained as it is being placed in the forms.  Usually, such tests cannot be conducted properly at the point of use, but the sample can be obtained and removed to a convenient site for immediate slump determination.  By correlating such tests with tests on the same concrete being discharged from hauling units several times a day, the difference in slump can be determined and applied to all other tests conducted on concrete from the hauling units.  In this manner, there will be less interruption in production and less interference in conducting the tests.

At the ready mix and central mix plants, loads may be checked for slump so that appropriate adjustments may be made to avoid shipment and rejection of concrete at the work site.  Loads that only slightly exceed the slump requirements when tested at the plant should not be rejected. However, adjustment should be considered for subsequent loads to avoid the possibility of rejecting succeeding loads.

Conducting tests at the plant does not eliminate the necessity of conducting test at the site.  Further tests will be required as the concrete is being placed.

The specification requirements for slump vary depending on the type of work being constructed.  Table 499.03-3 lists the required nominal slump and the maximum slump in inches (millimeters).  These slumps are achieved using water and any required admixture.  If the Contractor wants more slump than specified on Table 499.03-3, a Type F or Type G admixture may be used, and the nominal slump may be increased to 6 inches (150 mm) and the maximum slump may be increased to 7 inches (180 mm).  The higher slump is allowed regardless of the type of work.

A retarding admixture (Type B or D) is required in all concrete if the plastic concrete temperature exceeds 75° F (24° C).  The admixture must be dispensed in accordance with the admixture manufacturer's recommendations and the water cement ratio must not be exceeded.

Slump must be maintained at the specified nominal slump, except that an occasional load, exceeding the nominal range, but within the maximum slump limit, may be used.  This is allowed provided an immediate adjustment is made to reduce the slump of succeeding loads to within the nominal slump range.  Before using concrete exceeding the nominal slump, the Contractor or supplier must take positive action to reduce the slump of following loads.  If the high slump was the result of adding too much water at the site, less water should be added to the next load.  If high slump results from water added at the plant, notify the plant before using the batch and order an immediate reduction in water.  Use of concrete having the slump between nominal and maximum should be restricted to an occasional load.

Slump Test (ASTM C 143)

Start the slump test within five minutes of obtaining a composite sample. The inner surface of the slump cone is dampened and placed on a clean, flat, moist, non-absorbent, rigid surface, such as a smooth plank.

Figure 499.A – Pulling the Slump Cone Vertically from a Prepared Sample

Figure 499.B – Equipment Necessary for the Slump Test- Slump Cone, Tamping Rod, Scoop, and Ruler

Component Parts and Accessories

1.        Slump cone – A metal mold in the shape of a cone with an 8-inch ± 1/8-inch (203-mm ±3.2 mm) diameter base, a 4-inch ± 1/8-inch (102-mm ±3.2 mm) diameter top that is 12 inches tall.  The mold must be made of metal no thinner than 0.045 inch (1.14 mm).  The inside metal surface must be smooth.

2.        Accessories

3.        Tamping rod – A straight, 5/8-inch (16 mm) diameter rod that is approximately 24 inches (600 mm) long with a rounded (hemispherical) tip.

4.        Ruler – A ruler or tape to measure the slump of the sample.

5.        Scoop – A metal scoop that is used to place the concrete sample into the slump cone.

Method of Operation

The Inspector holds the cone firmly in place, while it is being filled, by standing on the foot pieces.

The mold is filled in three layers, each approximately one-third the volume of the mold: the first layer approximately 2 1/2 inches (67 mm) deep, the second layer 6 inches (155 mm) deep, and the third layer 12 inches (305 mm) to the top of the cone.

In placing each scoop of concrete in the slump cone, the scoop is moved around the top edge of the cone as the concrete slides from it in order to ensure uniform distribution of concrete within the cone.

Each layer is rodded 25 strokes with the tamping rod.  The strokes are distributed in a uniform manner over the cross-section of the mold and should penetrate into, but not through, the underlying layer.  The bottom layer is rodded throughout its depth.

In filling and rodding the top layer, the concrete is heaped above the mold and any excess is maintained above the top while rodding.  After the top layer has been rodded, the surface of the concrete is struck off with the tamping rod so that the mold is exactly filled.

Next, release the foot pegs while pressing down firmly on the hand holds on the slump cone, while being careful to keep the cone firmly on the base.  Remove any excess concrete at the base of the slump cone.

Lift the slump cone straight up in one steady motion.  The operation of raising and removing the mold is performed in 3 to 7 seconds by a steady, upward lift, with no lateral or twisting motion being imparted to the concrete sample.

The slump is the distance the concrete drops from the original height of the sample, which is 12 inches (305 mm).  To measure the distance, place the slump cone beside the slumped concrete and place the tamping bar on top of the cone so that the bar is level and above the displaced original center of the sample.  Measure the distance from the displaced original center of the sample to the bottom of the tamping rod.  The distance measured is the slump of the concrete.

Figure 499.C – Measurement of Slump

The entire operation from the start of filling through mold removal must be completed within the elapsed time of 2-1/2 minutes.  The slump must be recorded in inches (millimeters) to the nearest 1/4-inch (6 mm).  Slump cone test results should be recorded in the column labeled, "Slump Inches (millimeters)," on the TE-45 Report.

Concrete Yield

The yield of a concrete batch is the volume that it occupies.  Concrete is sold by volume, but it is batched by the weight of each ingredient.  This test is not specifically required for QC/QA specifications.  It is the Contractor’s responsibility.  For non QC/QA concrete, the Inspector should run a QA for each day's production after the slump and entrained air content have been properly adjusted.  A yield test is then done to confirm the volume of concrete in the batch. 

Yield tests are made whenever the yield is in doubt, after adjustments are made in the mix, or when cylinders or beams are cast.  Unless the quantity of concrete to be mixed is small, at least two tests should be made each day.

Yield must be within a tolerance of ± 1 percent at the design air content and at the specified slump.   Therefore, 1 cubic yard (27 cubic feet) may vary from 26.73 to 27.27 cubic feet per cubic yard (1 cubic meter may vary from 0.99 to 1.01 cubic meter).  An 8 cubic yard load is 216 cubic feet (8 x 27 cu.ft. / cu.yd.).  This load may vary from 213.84 to 218.16 cubic feet (a 7-cubic meter load may vary from 6.93 to 7.07 cubic meters).  A consistent over- or under-yield, even within the tolerance, should be corrected in order to maintain the correct cement factor.

Yield Test (ASTM C 138)

The yield is calculated by performing a field test to determine the unit weight of a representative sample of concrete taken from the batch.  The Department uses the bottom pot of the pressure meter to determine the unit weight of a concrete sample.  The unit weight of the concrete is then used to calculate the yield by the following formula:

Equation 499.18 – Yield

Unit weight is the ratio of the weight of a material to the volume that it occupies.  Unit weight is expressed in pounds per cubic foot (kilograms per cubic meter). 

Figure 499.D – Equipment Used for the Yield Test

Figure 499.E – Scale Used for the Yield Test

Component Parts and Accessories

1.        A volume measure, a pressure meter air pot at least 0.20 ft³ (0.006 m³.) capacity.  The container volume must be known or an air pot factor must be determined prior to use.

2.        Accessories

a.        Strike-off bar.

b.        Scoop.

c.        Strike-off plate – A flat square plate at least 2 inches wider than the diameter of the measure and at least 1/4 inch (50 mm) thick if made of steel and 1/2 inch thick if made of glass.

d.        Tamping rod – A straight 5/8-inch (16 mm) diameter steel rod which is approximately 24 inches (600 mm) long with a rounded (hemispherical) tip.

e.        Scale – A scale of a capacity to weigh the pot filled with concrete.

f.         Rubber mallet, 1.25 ± 0.50 lbs (0.6 kg ± 0.25 kg).

Figure 499.F – Yield Test – Bucket is Filled in Three Equal Layers

Method of Operation

The concrete yield is determined as follows:

1.        To determine the unit weight of a concrete sample, first weigh the bottom of the empty air pot to the nearest 0.01 pound (0.005 kg).

2.        Next, fill the measure with concrete, representative of that being placed in 3 equal layers, rodding each layer with 25 strokes of the tamping rod.  After rodding each layer, tap the measure on the sides 10 to 15 times with an appropriate mallet to close any voids left by the tamping rod and to release any large bubbles of air that may have been trapped.

3.        After the consolidation is completed, strike-off excess concrete and finish even with the top edge of the measure with the metal strike-off plate.  After strike-off, clean all excess concrete from the exterior of the measure and determine the gross weight of the measure and the concrete sample.

4.        Calculate the net weight of the concrete sample in pounds (kilograms) by subtracting the weight of the measure from the gross weight.

5.        The net weight of the concrete sample is then used to determine the unit weight.  The unit weight is the product of the net weight of the sample under test and the air pot factor as follows:

Equation 499.19 – Unit Weight

The air pot factor is the inverse of the volume of the air pot in cubic feet, as shown in Equation 499.20:

Equation 499.20 – Air Pot Factor

Therefore, an air pot volume of 1/4 cubic feet or 0.25 cubic feet would have a pot factor as follows:

Note:  The air pot factor is determined by a Laboratory test and is written on the side of all air pots.  This factor is determined by a calibration process described in the section entitled, Determination of the Air Pot Factor.

When the air pot factor is multiplied by the net weight of the concrete sample that is consolidated and struck off into the air pot’s volume (per Equation 499.19), mathematically it is the same as dividing the net weight of the sample by the volume of the concrete sample weighed.  This gives the Unit Weight of the sample in pounds per cubic foot (kilograms per cubic meter).

The calculated unit weight of the concrete is the number of pounds per cubic foot (kilograms per cubic meter) for the sample under test.  The unit weight is used to calculate the yield.

Next, calculate the yield using Equation 499.18:

The total batch weight of the concrete is the weight of all the ingredients used in the batch or a cubic yard. This includes cementitious materials, moist coarse and fine aggregate, water added at the plant, plus any water added at the job site to adjust slump.  This total batch weight is divided by the unit weight of the concrete sample to determine yield.  The yield is the number of cubic feet (cubic meters) of concrete in the batch.

Example:

The following are the batch weights for an 8-cubic yard (7-cubic meter) load of concrete, delivered to the project:

English (lbs)

Metric (kg)

1

Cement

4,800

2,492

2

Fine Aggregate

10,698

5,550

3

Coarse Aggregate

13,229

6,868

4

Water

1,664

864

5

Total Batch Weight (1+2+3+4)

30,391 lbs

15,774 kg

An air pot with an air pot factor of 4.022 (141.24) is weighed empty and determined to be 7.98 lbs (3.62 kg).  The gross weight of the air pot and the concrete sample is determined to be 43.52 lbs (19.83 kg).  Determine the unit weight of the sample and the yield of the batch of concrete.

First determine the net weight of the concrete sample:

Gross wt. of measure + concrete                             43.52 lbs (19.83 kg)

Tare weight of measure empty                                -7.98 lbs (- 3.62 kg)

Net weight of concrete sample                                35.54 lbs (16.21 kg)

Now that the net weight of the sample is known, the unit weight is determined by the use of Equation 499.19 as follows: 

Unit Weight     = 

                                = 35.54 x 4.022       (16.21 x 141.24)

                                = 142.94 lbs/ft³       (2289.5 kg/m³)

Next, determine the yield of the 8-cubic yard (7-cubic meter) load of concrete by using Equation 499.18 as follows:

= 212.61 ft³

In English units, the intended number of cubic feet per batch is determined by multiplying the number of cubic yards in the batch by 27 cubic feet per cubic yard (27 x 8 = 216 = the intended number of cubic feet per batch).  If the number of cubic feet per batch, as determined by the yield test, is within 1 percent of the design, at the specified air and slump, no change is necessary in the batch weights.  However, if the volume of concrete is not within 1 percent of the intended volume, or if there is a continued over-yield or under-yield even though within 1 percent, then a yield adjustment must be made.  A yield adjustment involves reducing or increasing the batch weights to correct an over-yield or under-yield situation.

In the above example, 8 cubic yards or 216 cubic feet was the intended yield but the calculated yield was 212.61 cubic feet.  Therefore, there was an under-yield of 1.6 %, which exceeds the allowable 1%.  To correct this under-yield the batch weights of the coarse and fine aggregate batch weights must be increased (thus adding more volume of material to the batch).  Adjustment to correct an over-yield or under-yield should be based on the absolute volume of dry material.

In Metric units, the yield is compared to the design number of cubic meters batched to determine if the batch is within the one percent yield tolerance. The allowable deviation in yield for a 7 m³ batch is 6.93 m³ to 7.07 m³.  In the above example, the yield was found to be 6.89 m³, which is less than the allowable range.  Again, this under-yield situation requires an adjustment in the batch weights.

Form C-45, Concrete Control Test Form, is provided for documenting and calculating the tests run in the field.  A copy of this form is shown in Figure 499.A

Figure 499.G - Concrete Control Test Form C-45

Making a Yield Adjustment

Assume the actual calculated number of cubic feet (cubic meters) per batch is 212.61 cubic feet (6.89 cubic meters), which is more than 1 percent under the 216-cubic foot (7.0-cubic meters) intended volume.  Therefore, the batch weights must be increased.  Equation 499.21 shows the calculation of the under-yield:

Equation 499.21 – Under-yield Calculation

Where:

                Percent OY or UY= Percent Over-Yield or Percent Under-Yield

If the number obtained by Equation 499.19 is a negative number, there is an under-yield and volume must be added to get the yield back to the intended yield.  Conversely, if the number is positive, there is an over-yield situation and volume must be removed from the batch to reduce the yield back to the intended yield.

Using the example numbers, the Percent Under- or Over-Yield can be determined:

Percent OY or UY =    

 The total batch weight should be increased to adjust the under-yield.  Since the batch of concrete did not produce the intended volume, additional volume of material must be added to adjust the under-yield.  Adjustments are made in the fine and coarse aggregate based on absolute volume. The cement is the minimum specified, and therefore, is not changed.  Water may vary slightly, and must be considered in making the adjustment. The calculations for adjusting the mix are as follows:

Total under-yield = 216 ft³ - 212.61 ft³ = 3.39 ft³ (7.00 m³ - 6.89 m³ = 0.11 m³)

Thus, the 8 yd³ (7 m³) load must be adjusted by adding 3.39 ft³ (0.11 m³) of volume.  By adding this much volume to the load, the yield should increase in subsequent loads after the adjustment is made.  The volume needed to adjust the under-yield is replaced with sand and stone in the same proportion as in the original concrete sample.

Next, determine the percent of fine and coarse aggregate in relation to the total aggregate weight in the original mix design. For this calculation, the corrected SSD design weights are to be used.

Fine aggregate (SSD)              10,160 lb                  (5271 kg)

Coarse aggregate (SSD)          12,944 lb                 (6720 kg)

Total Aggregate (SSD)           23,104 lb                 (11,991 kg)

% Fine Aggregate =

% Coarse Aggregate =

Next, determine the proportion of the 3.39 cu. ft. (0.11 cubic meters) under-yield volume that must be fine and coarse aggregate.  These adjustments maintain the same proportion of aggregate in the adjusted mix design as was in the original mix design.

Fine Aggregate        = 3.39 ft³ x 0.44      = 1.49 ft³ (= 0.11 m³ x 0.44 = 0.048 m³)

Coarse Aggregate    = 3.39 ft³ x 0.56      = 1.90 ft³ (= 0.11 m³ x 0.56 = 0.062 m³)

Total                        = 3.39 cu. ft³           (= 0.110 m³)

Now that the absolute volume of fine aggregate and coarse aggregate necessary to correct the under-yield are known, the weight of each material can be calculated since the specific gravities of each aggregate are known.

Fine Aggregate Adj                 =1.49 ft³ x 2.59 x 62.4 lbs/ ft³ (Equation 499.6)

                                                = 241 lbs

                                                = (0.048m³ x 2.59 x 1000 kg/m³) (Equation 499.7)

                                                = (124 kg)              

Coarse Aggregate Adj             =1.90 ft³ x 2.63 x 62.4 lbs/ft³  (Equation 499.6)

                                                = 312 lbs

                                                = (0.062 m³ x 2.63 x 1000 kg/m³) (Equation 499.7)

                                                = (163 kg)              

Thus from the above, it can be seen that 241 lbs (124 kg) of fine aggregate and 312 lbs (163 kg) of coarse aggregate are required to adjust the yield of this 8-cubic yard (7-cubic meter) load.

If the mix appears to be over-sanded, only the coarse aggregate needs to be adjusted. However, if the mix appears under-sanded, or bony, the adjustment should be in the fine aggregate only.

The adjustments in the SSD weight of fine and coarse aggregate for the above example are as follows:

Fine Aggregate        10,160 + 241 = 10,401 lb (5,271 + 124 = 5,395 kg)

Coarse Aggregate    12,944 + 312 = 13,256 lb (6,720 + 163 = 6,883 kg)

The new adjusted batch weights must next be determined, and the water-cement ratio must be checked to make sure the specified water-cement ratio is not exceeded with the new batch weights.

Determination of the Air Pot Factor

This test is done by the Laboratory or the District Test Lab and is shown here. 

The air pot container is filled with water at room temperature and the top covered with a glass plate to eliminate all air bubbles and excess water.  Determine the weight of water in the measure to the nearest 0.01-pound (.005 kg).  Measure the temperature of the water and determine its density from the table below:

Density of Water

English

Metric

Temperature
(Degrees F)

Density
(lbs /cu. ft.)

Temperature
(Degrees C)

Density
(kg/ m³)

60

62.366

16

999.10

65

62.337

18

998.64

70

62.301

21

998.06

75

62.261

24

997.42

80

62.216

27

996.70

85

62.166

29

995.90

Calculate the air pot volume factor by dividing the density of water (from the table) by the weight of water required to exactly fill the measure.  Measures should be calibrated once each year and the pot factor painted on the measure.  This air pot factor should be nearly 4.000 (141.24) indicating that the measure is about 0.25 cubic foot (0.00708 m³) of volume.

Example:

Assume the temperature of the water used to fill the air pot bottom is 70º F and the following is determined in the laboratory:

1.        Weight of air pot bottom empty plus the glass plate =             8.98 lbs

2.        Weight of air pot bottom plus glass plate plus water =            24.47 lbs

3.        Weight of water in air pot bottom = (2) - (1)           =              15.49 lbs

4.        Density of water at 70º F, from the above table      =              62.301 lbs/cu.ft.

Total Air Tests (ASTM C 231 or ASTM C 173)

The air content of concrete is measured by a standard test in accordance with either ASTM C 231 (Pressure Meter Method) or ASTM C 173 (Volumetric Method).

Figure 499.H – Pressure Meter Method

Figure 499.I – Volumetric Method

Air tests must be made for several loads or batches at the start of daily production and after any adjustment in the batch weights.  A test is made whenever it is suspected that adequate air entrainment is not being maintained.  An air test must also be made when a yield test is made and when cylinders or beams are cast.

The requirements apply at the point of use; therefore, these tests must be made by the concrete control Inspector at the job site.  However, it may be desirable to check the air content of the concrete at the plant for the first few batches of the day and also after any adjustment has been made in the concrete mix design.  These checks can detect deficiencies in air content at the plant where immediate corrections can be made.

The approximate amount of entrained air may be determined quickly by using a Chace Indicator.  Every load of transit mix concrete used in superstructures must be checked for air entrainment.  The Chace Indicator permits a quick check of every load.  Its use also is desirable for all concrete work to quickly check the requirement for entrained air.  Whenever the specification limits are exceeded according to the Chace Indicator, a more accurate determination must be made using an air meter (Pressure Meter or Volumetric Meter).

Make a test from the same batch of concrete at least once a day using the Chace Indicator and an air meter to compare the results.  Comparison of these results provides the Inspector with a guide when using the Chace.  If the Chace indicates 4.5 percent and the meter test result is only 4.0 percent, the air must not be permitted to drop below 4.5 percent when checked using the Chace.

Use a Pressure Meter or Volumetric Meter to determine the air content to be reported when making yield tests and when casting cylinders.  An accurate determination is necessary in each case; therefore, an accurate test is required.

A Chace Indicator and Volumetric air pot can be used for all types of concrete.  The Pressure Meter must not be used when slag or light weight coarse aggregate are used in the concrete.  The Pressure Meter is limited to concrete consisting of relatively dense coarse aggregate such as gravel or limestone.  A Volumetric Meter test must be used when slag or lightweight aggregates are used.  Detailed explanation of each method follows. 

Air Content of Freshly Mixed Concrete by the Pressure Meter (ASTM C 231)

This test method is used with dense aggregate concretes for which the aggregate correction factor can be determined.  This method is not applicable to light weight aggregates, air-cooled blast furnace slag, or aggregates of high porosity.  If these aggregates are incorporated, a volumetric air test (ASTM C 173) must be used.

This air test measures the entrapped and entrained air in the concrete sample.  The air content from this test is the apparent air content of the sample.  A separate test is made on the aggregates used to make the concrete to determine an aggregate correction factor for the concrete aggregates.  This percentage value is subtracted from the apparent air content to obtain the amount of entrained air in the concrete.  Department specifications specify the amount of entrained air that is required in the concrete at the point of use.

Figure 499.J – Assembled Pressure Meter

Figure 499.K – Equipment Necessary for Pressure Meter Test

The Pressure Meter Test is performed as follows:

Parts and Accessories

1.        Component Meter.

a.        Pot at least 0.20 ft³ (0.006 m³) capacity.

b.        Top, including gauge, pump, and clamps.

2.        Accessories.

a.        Calibration cylinder.

b.        Section of straight tubing.

c.        Section of curved tubing.

d.        Strike-off bar.

e.        16-mm (5/8") Tamping rod.

f.         Rubber syringe.

g.        Rubber mallet, 0.6 kg ± 0.25 kg (1.25 ± 0.50 lbs).

h.        Wooden carrying case.

Method of Operation

Follow these steps to use a Pressure Meter to determine the percentage of air in a sample of concrete:

1.        Place a representative sample of the concrete in the bowl in three equal layers, consolidating each layer by 25 strokes of the tamping rod distributed over the entire cross-section of the bowl.  After each layer is rodded, tap the sides of the measure smartly 10 to 15 times with the rubber mallet to close any voids left by the tamping rod and to release any large bubbles of air that may have been trapped.  Rod the bottom layer through its depth, but do not forcibly strike the bottom of the bowl.  When rodding subsequent layers penetrate the previous layer only about 1 inch (25 mm).

2.        Strike off the concrete surface, level full using the straightedge (or a plate when determining the unit weight), then clean the edge and exterior of the pot thoroughly.

3.        At this point, the pot and sample is weighed.  This gross weight is documented for later use when determining the yield.

4.        Next, place the top on the pot and clamp securely.  Close the air valve between the air chamber and the bowl and open both petcocks.

5.        Using the rubber syringe, inject water through one petcock until all air is expelled through the opposite petcock.  Leave petcocks open.

6.        With built-in pump, pump up air to the "Initial Pressure" line on gauge.  This initial pressure line is given on the paper in the carrying case lid.

7.        Wait a few seconds for the compressed air to cool to normal temperature and then stabilize the gauge hand at the proper initial pressure line by pumping or bleeding off as needed.

8.        Close both petcocks and press down on the thumb lever to release air into the base. Hold thumb lever down for a few seconds.  Tap the sides of the bowl several times sharply with the mallet.  Lightly tap the gauge to stabilize the hand on the dial.

9.        Read and record the percent of air entrainment as shown on the gauge.  This is the apparent air content of the concrete in percent.

10.     The true percentage of air-entrained in the concrete is the apparent air content, as found is in 9 above, minus the aggregate correction factor as determined is in the following section entitled, Determination of Aggregate Correction Factor.  Therefore, subtract the aggregate correction factor from the apparent air content found in 9 and record it on the TE-45 Report as percent of entrained air in concrete.

Determination of Aggregate Correction Factor

Since aggregate particles generally are porous, they contain a small amount of volume of air that is included in the apparent air content, as measured in 9 above.  This volume percentage must be deducted from the total air content percentage to obtain the true entrained air content of the concrete.  To obtain the aggregate correction factor it is necessary to run an air determination (with the pressure meter) on equivalent amounts of fine aggregate and each size of coarse aggregate that would be contained in the air pot volume of concrete.  This factor varies with different aggregate sources and must be determined by actual tests.  The aggregate correction factor is determined prior to any concrete placement and is applied as long as there is no change in the source of the aggregate or proportioning used in the concrete under test.

The Aggregate Correction Factor is determined as follows:

1.        The amount of each aggregate to be used in the test is determined by dividing the volume of the air pot by the intended volume of the concrete batch.  This ratio is multiplied by the actual batch weight of the particular aggregate that was used in the concrete.  Use equation 499.24 to determine the weight of each aggregate to be used in the test.

Equation 499.24 – Weight of each Aggregate

Where:

                APV = Air Pot Volume in cubic feet (m³)

                IBV= Intended Batch Volume in cubic feet (m³)

                ABW = Aggregate Batch Weight in lbs. (kg) for the intended volume

Example:

Given the following information determine the amount of fine and coarse aggregate necessary for an aggregate correction test:

                Volume of Air Pot = 0.25 ft³ (0.00708 yd³)

                Intended Volume of Concrete per Batch = 8 yd³ or 216 ft³ (7 m³)

                Aggregate Batch Weight for Fine Aggregate = 10,698 lbs (5550 kg)

                Aggregate Batch Weight for Coarse Aggregate = 13,229 lbs (6868 kg)

Fine Aggregate Weight

(Equation 499.24)

(Equation 499.24)

Coarse Aggregate Weight

(Equation 499.24)

(Equation 499.24)

Therefore, 12.38 pounds (5.6 kg) of sand and 15.31 pounds (6.9 kg) of stone are used to determine the correction factor.

2.        Fill the air pot one-third full of water.  Carefully add a portion of the coarse aggregate then a portion of the fine aggregate.  Jar the pot and rod the aggregate to eliminate any entrapped air.  Carefully repeat, adding portions of each aggregate until all the aggregate is inundated into the pot.  Each aggregate addition must be added carefully as instructed in order to get the entire quantity into the volume of the pot.  Make sure that aggregate in the pot remains submerged at all times.  If the sand is not rodded into the voids between the coarse aggregate particles, the aggregate quantities will overflow the pot.  Aggregates should be in approximately the same moisture condition as those used in the concrete.

3.        Strike-off any excess foam and keep the aggregates inundated for a period of time approximately equal to the time between introduction of water into the mixer at the concrete plant and the time of performing the air test in the field.

4.        Screw the short piece of straight tubing into the threaded petcock hole on the underside of the top cover. Place the top on the pot and clamp securely.  Close the air valve between the air chamber and the measuring bowl and open both petcocks.

5.        Add water with a syringe through the petcock having the pipe extension below until all air is expelled from the second petcock.  Leave both petcocks open.

6.        Pump up the air pressure in the air chamber to a little beyond the initial pressure line marked in the carrying case lid.  Wait a few seconds for the compressed air to cool to normal temperature, and then stabilize the gauge at the proper initial pressure line by pumping or bleeding off air as needed and tapping the gauge slightly.

7.        Screw the curved tube into the outer threaded end of the petcock.  Close both petcocks and press the thumb lever to release the air into the bowl.  Fill the 5 percent calibrating vessel level full of water from the base by controlling the flow of water with the petcock valve on the curved tube.

8.        Release the air at the free petcock and let the water in the curved pipe run back into the base. The air meter now has 5 percent of its volume removed.

9.        With both petcocks open, pump the air pressure in the air chamber to slightly beyond the initial pressure line. Wait for the compressed air to cool, and then stabilize the gauge hand at the proper initial pressure line by pumping or bleeding off air as needed and tapping the gauge slightly.

10.     Close both petcocks and press the thumb lever to release the air into the bowl.

11.     Read and record the air content shown on the meter. The aggregate correction factor will be the difference between the air content on the meter minus 5 percent.

Note: Normally the aggregate correction factor will be between 0.1 and 0.8 percent.  This factor will ordinarily remain constant (with limestone or gravel coarse aggregate) for the same combination and quantity of aggregate.  It is essential, therefore, to determine the aggregate correction factor accurately since any errors made in the factor will be reflected in all air content determinations. BE SURE THAT ALL AIR ENTRAPPED IN THE INUNDATED AGGREGATE IS ELIMINATED WHEN PREFORMING THE TEST.

Checking Calibration of Gauge

All Pressure Meters are calibrated and tested for leaks.  Any changes found in the manufacturer’s initial pressure line is marked in red on the paper in the carrying case lid, before the meters are issued by the Laboratory.  However, rough handling or worn or damaged parts will affect the calibration.  Therefore, the operator should check the meter every 3 months. The method of checking is as follows:

1.        Fill the base with water.

2.        Screw the short piece of straight tubing in the threaded peacock hole on the underside of the cover.  Clamp cover on the base with the tube extending down into the water.

3.        With both petcocks open, add water with syringe through the petcock having the pipe extension below, until all air is forced out of the opposite petcock. Leave both petcocks open.

4.        Pump up air pressure to a little beyond initial pressure line marked in carrying case lid. Wait a few seconds for the compressed air to cool to normal temperature and then stabilize the gauge hand at the proper initial pressure line by pumping or bleeding off as needed.

5.        Close both petcocks and immediately press down on the thumb lever exhausting air into the base. Wait a few seconds until the hand is stabilized. If all the air was eliminated and the initial pressure line was correctly selected, the gauge should read 0 percent. If two or more tests show a consistent variation from 0 percent, then change the initial pressure to compensate for the variation. Use the newly established initial pressure line for subsequent tests.

6.        Screw the curved tube into the outer end of petcock, and by pressing on the thumb lever and controlling flow with petcock lever, fill the 5 percent calibrating vessel lever full of water from the base.

7.        Release the air at the free petcock.  Open the other petcock and let the water in the curved pipe run back into the base. There is now 5.0 percent air in the base.

8.        With petcocks open, pump air pressure in the exact manner as outlined in Step 4 above.  Close petcocks and immediately press the thumb lever. Wait a few seconds for the exhaust air to cool to normal temperature and for the needle to stabilize.  The dial should now read 5.0 percent.

9.        If two or more consistent tests show that the gauge reads less than 4.9 percent or more than 5.1 percent then remove the gauge glass and reset the dial hand to 5.0 percent by turning the recalibrating screw located just below and to the right of the center dial.

Air Content of Freshly Mixed Concrete by Volumetric Method (ASTM C 173 modified for ODOT use)

This test method can be used on concrete containing any type of coarse aggregate.  This method gives the total air content, which includes both entrapped and entrained air.  This method must be used if lightweight coarse aggregate, air-cooled blast furnace slag coarse aggregate or aggregate of high porosity is used in the concrete under test.

The method involves taking a known volume of concrete and breaking it down by washing it with water in a sealed container.  A fixed amount of water is used to wash the sample of concrete in the container.  After the washing, the volume of the sample and wash water decreases by the volume of air washed from the known volume.

Figure 499.L – Assembled Brass Volumetric Air Meter

Figure 499.M – Plastic Volumetric Air Meter and Accessories

Parts and Accessories

1.        Meter.

a.        Bottom Pot, 0.075 cu. ft. (2.1 L) capacity.

b.        Top cone, including gauge glass, clamps and top plug.

2.        Accessories.

a.        Water filler and dispersion tube.

b.        Strike-off bar.

c.        5/8-inch (16 mm) diameter tamping rod.

d.        Brass cup capacity 23 milliliter.

e.        Small rubber syringe.

f.         Can of 70 percent isopropyl alcohol (poison).

g.        Rubber mallet 1.25 ± 0.50 lbs (0.6 kg ± 0.25 kg).

h.        Carrying case.

Method of Operation

The percent of entrained air in a sample of concrete is determined as follows using the volumetric air meter:

1.        Place a representative sample of the concrete in the bowl in two equal layers, consolidating each layer by 25 strokes of the tamping rod. After each layer is rodded, tap the sides of the measure 10 to 15 times smartly with the rubber mallet to close any voids left by the tamping rod and to release any large bubbles of air that may have been trapped.

2.        Strike-off the concrete surface, level full using the straightedge.

3.        Place the cone on the pot and clamp securely.

4.        Insert the dispersion tube into the neck of the meter.  Add at least one pint of water followed by one pint of isopropyl alcohol.  Continue adding water until it appears in the graduated neck of the top section of the meter.  Remove the dispersion tube.  Bring the water level up until the bottom of the meniscus is even with the 0 mark.

5.        Attach and tighten the water-tight cap.

6.        Repeatedly invert and agitate the unit for a minimum of 45 seconds to free the concrete from the base.  Do not invert the meter from more than five seconds at a time.

7.        Tilt the meter approximately 45 degrees and vigorously roll and rock the meter for approximately 1 minute keeping the neck elevated at all times. 

8.        Set the meter upright and allow it to stand while the air rises to the top until the liquid stabilizes.  Consider the liquid stabilized when it does not change more than 0.1 percent within a one-minute period.

9.        If the liquid level is obscured by foam, use the rubber syringe to add sufficient alcohol from a calibrated cup equaling 1 percent of the base’s volume.  Record the number of calibrated cups of alcohol required to disperse the foam.

10.     Repeat the rolling and rocking procedure until two consecutive readings do not differ by more than 1/4 percent.

11.     Once the level has stabilized, determine the level of water in the neck of the meter to the nearest 1/1/4 percent.  Add the number of cups of alcohol used to disperse the foam to the meter reading.

12.     Disassemble and empty the contents in the bowl and examine the bowl to make sure that all of the concrete was dislodged during the agitating and rolling and rocking procedures.  If there is a significant amount of concrete remaining in the bowl, the test is invalid and must be redone.

Chace Air Indicator for Determination of Entrained Air (AASHTO T-199)

This method of test covers the determination of the air content of freshly mixed concrete by displacing the air with alcohol and observing the change in level of the liquid in a tube. The apparatus is light and small, and the test procedure requires only a few minutes.

This method is satisfactory for determining the approximate air content of freshly mixed concrete. It should not, however, be considered suitable for replacing the pressure method) or volumetric method and in no case should the value obtained through the use of this method be accepted as determining the compliance of the air content of concrete with the requirements of specifications. The method is most useful for determining whether the concrete has a low, medium, or high air content and whether the air content is reasonably constant from batch to batch of concrete.

Parts and Accessories

1.        Air Indicator.

a.        0.22 cubic inches (3.6 ml) capacity cup.

b.        Rubber stopper.

c.        Glass top.

2.        Accessories.

a.        Rubber syringe.

b.        Tamping blade.

c.        Can of 70 percent isopropyl alcohol (poison).

Figure 499.N – Chace Air Indicator Equipment

Method of Operation

The percent of entrained air in a sample of concrete is determined as follows:

1.        Fill the metal cup with cement mortar taken from the concrete, from which any particles larger than a No. 10 (2.00 mm) sieve have been removed with the tamping blade.  A No. 10 (2.00 mm) sieve has openings of 0.0787 inches (2 mm) wide or a little less than 3/32 inches (2.38 mm). Use the tamping blade to pick up mortar.  The mortar should not be wet screened to remove the material larger than a No. 10 (2.00 mm) sieve.  Spade material into the cup with tamping blade to compact the mortar.  Strike-off excess even with top of cup.

2.        Hold finger over stem opening of glass top and fill the glass tube with alcohol to the marked line about 1 inch (25 mm) from the large end of the glass.

3.        Carefully insert cup filled with mortar into the glass top and turn indicator to a vertical position with the graduated stem up.  Be sure stopper is firmly in place.  Adjust liquid to top line of stem by adding alcohol with syringe, making sure that all air bubbles are removed.  This can be done by slightly tilting the indicator.

4.        Place finger over the stem opening to prevent liquid loss.  Gently roll the indicator from vertical to horizontal and back several times until the mortar has been washed out of the cup.

5.        With the indicator in the vertical position, carefully remove finger from the opening and count the number of spaces from the top line to the new liquid level estimating to the nearest 0.1. Each space represents 1 percent of entrained air.  The air indicator is designed to read directly for a concrete mix having 15 cubic feet of mortar per cubic yard (0.56 cubic meters of mortar per cubic meter) of concrete.  Therefore, the air content as determined by each test must be corrected for mixes with different mortar content.

6.        No conversion factor is used when gravel coarse aggregate is used in the concrete mix. In this case, the percentage of entrained air is read directly from the stem.  However, when limestone or slag is used, it is necessary to multiply the stem reading by 1.05 to determine the percentage of entrained air.  Record the result to nearest 0.1 percent.

Figure 499.O – Chace Air Indicator

Temperature of Freshly Mixed Portland Cement Concrete (ASTM C -1064)

Parts and Accessories

Container – The container must be large enough to provide at least 3 inches (75 mm) of concrete in all directions around the sensor of the temperature-measuring device.

Temperature Measuring Device – The device used must be capable of measuring freshly mixed concrete to ± 1° F (± 0.5° C) throughout the entire temperature range to be encountered.

Figure 499.P – Concrete Thermometer

Method of Operation

The temperature of freshly mixed concrete may be measured in the transporting equipment provided the sensor of the temperature measuring device has at least 3 inches (75 mm) of concrete cover in all directions. The temperature is measured as follows:

1.        Place the temperature measuring device in the freshly mixed concrete so that the temperature sensing portion is submerged a minimum of 3 inches (75 mm).

2.        Gently press the concrete around the temperature-measuring device at the surface of the concrete so that the ambient temperature does not affect the reading.

3.        Leave the temperature-measuring device in the freshly-mixed concrete for a minimum of 2 minutes or until the temperature reading stabilizes, then read and record the temperature.

4.        Complete the temperature measurement within 5 minutes after obtaining the sample.

5.        Report the temperature to the nearest 1°F (0.5 °C)

Gradation of Aggregate

If aggregate is from a certified source there is no need for further sampling and testing.  However a routine sieve analysis can be made to check compliance with gradation requirements.  Gradation can be checked if there are questions about the concrete you are getting.  If there is an issue, obtain a representative sample and send to the District Test Lab for evaluation and results.

Making and Handling Concrete Cylinders (ASTM C-31)

The preparation and handling of concrete test specimens are an important part of the Inspector's duties, since the cylinders furnish an indication of the quality of the concrete being produced as the work progresses. Cylinders must be made and handled strictly in accordance with the following instructions.

On structures over 20-foot (6.1 m) span, three  test cylinders 4 inches (100 mm) in diameter and 8 inches (200 mm) high are made from each 200 cubic yards (150 m³) of each class of concrete, or fraction thereof, incorporated into the work.  On structures of 20-foot (6.1 m) span or less and bridge deck overlay projects, at least two cylinders are made for each 50 cubic yards (40 m³) of each class of concrete.

Parts and Accessories

1.        Cylinder molds

2.        Scoop

3.        3/8-inch (16 mm) steel tamping rod

The cylinder molds are placed on a firm, level surface, such as a board, so that the bottoms will not become deformed in the process of making the cylinders.

Cylinders are always made in sets of threes from the same batch of concrete.

Figure 499.Q – Equipment for Making Concrete Cylinders

Method of Operation

The molding of the specimens is performed as follows:

1.        With the scoop, fill each mold evenly one-half full of fresh concrete and rod each mold 25 times with the tamping rod, distributing the strokes evenly over the cross-sectional area of the mold and completely penetrating the layer of concrete.  The rod should lightly touch the bottom of the mold.  Tap the mold lightly 10 to 15 times to close any air voids left by the tamping rod.

2.        Finally, fill the mold to overflowing and rod 25 times as before. Again, the sides of the mold should be tapped lightly 10 to 15 times to close any voids left by the tamping rod.

3.        Using the tamping rod or trowel, strike-off the excess concrete flush with the top of the mold. This concludes the operation and there should be no further manipulation of concrete or mold. Specimens are made in one continuous operation.

4.        After making the three 4-inch x 8-inch cylinders, place lids on the cylinders.

5.        Install the retaining ring with three 4-inch diameter holes into the curing bucket.

6.        Place the cylinders into the curing bucket through the holes in the retaining ring. 

7.        In Hot Weather conditions, add water to the bucket to buffer the cylinders against the heat.  Shade the bucket from the sunlight.  Pour the water out of the bucket (for weight purposes) before transporting the cylinders to the lab

8.        In Cold Weather conditions, cover the buckets with thermal blankets, burlap and plastic, etc. to prevent heat loss and provide a heat source if possible. 

9.        For projects with a curing box required by 619.02, carefully move the cylinders in the buckets to curing box after 24 hours.  Otherwise, move the bucket to the field office to maintain samples within appropriate temperatures.

When cylinders are made, the following tests should also be made using concrete from the same batch:

1.        Slump

2.        Yield

3.        Concrete temperature

4.        Air test

Be sure and acquire a sufficient quantity of concrete to provide for all these tests.  Record the test values on the TE-45 Report or directly into a SiteManager sample on test screens.

1.        PCC INSPECTOR DAILY REPORT TE45 PART 1 – BATCH WT

2.        PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS

Reporting these values from the same batch as used for casting cylinders provides valuable data for evaluating compressive strengths of cylinders.  Therefore, always determine slump and air from the same batch of concrete used in cylinders.

Documentation:

Write the Specimen numbers on the cylinder molds.

Create a TE-10 tag with the SiteManager sample number and attach the tag to the handle of the bucket. 

Either one TE-31 form describing detailed information on the concrete to be tested or a screen print from the SiteManager test screen.  Put the paper in a plastic envelope and put the envelope in the bucket.

Concrete cylinders using ordinary Portland cement concrete mixes are prepared for shipment and sent to the District Laboratory 48 hours after molding.  If high-early-strength cement is used, cylinders are shipped to the District laboratory when required by the project but not sooner than 24 hours after molding

The three cylinders are packed in a shipping barrel with water and one TE-10 tag is taped before engaging the snap to the ring on the strap on the top of the case.  A filled out copy of a TE-10 tag is shown in Figure 499.B and a filled out copy of a TE-31 form is shown in Figure 499.C.

Cylinder test results will be reported in SiteManager in PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS screen.

When project concrete requires, “with QC/QA,” Contractor’s test results only need to be reported.  Make a SiteManager sample but only complete the PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS screen.  Do not complete the PCC INSPECTOR DAILY REPORT TE45 PART 1 – BATCH WT screen.

Figure 499.R - Filled Out TE-10 Tags

Figure 499.S - Filled Out SiteManager screen

Making Concrete Test Beams

When required by specification, the concrete control inspector will make and test concrete beams as described here, and report the results in the ODOT SiteManager as explained in Supplement 1023.

Where beam tests are made to determine when a section of pavement or base may be opened to traffic, two 6-inch x 6-inch x 40-inch (152 mm x 152 mm x 1016 mm) concrete beams are made using the same concrete being placed in the pavement or base. 

Section 511.14 Table 511.14-1b of the specifications requires falsework for structures to remain in place until the concrete has attained adequate strength as determined either by the length of curing time or by the testing of standard concrete beams.  When beams are desirable to determine removal of falsework, they must be made from the same concrete as that supported by the falsework.

The Laboratory (through the District Engineer of Tests) will provide the Inspector with the equipment for making and testing of concrete beams.

Parts and Accessories

1.        6-inch x 6-inch x 40-inch (152-mm x 152-mm x 1,016-mm) steel molds

2.        Spading tool

3.        Trowel

4.        Rubber mallet

5.        Beam testing machine

Figure 499.T – Equipment for Beam Testing

Method of Operation

The beams must be made as described here.  Beams must be made and tested in accordance with Supplement 1023.  Steel beam molds must be free of dirt, hardened concrete, or rust.  They are placed on a smooth, clean, level, and unyielding surface that has been lightly oiled to prevent the concrete from sticking.  The inside of each mold is oiled in the same manner.

1.        Using a shovel, fill each mold half-full with 3 inches (75 mm) of concrete representative of that in the batch.

2.        With the blade of the spading tool held at an angle to the ends of the mold, spade the concrete 20 times at equal intervals from one end of the mold to the other.

3.        Then, turning the blade of the spading tool, cross-spade 20 times at equal intervals back in the opposite direction of the end of the mold.

4.        Spade entirely around the side and ends of the mold.

5.        Tap along each side of the mold 15 times (total of 30 taps per lift) with the rubber mallet.

6.        Fill the mold to overflowing with concrete and repeat the spading and taping operations as before.

7.        Strike-off the excess concrete and trowel the concrete flush with the top of the beam mold.

8.        After concrete is set, the beam numbers are scratched into the concrete for future identification.

9.        Beams must be cured as nearly as possible in the same manner as the concrete from which they are made.

Pavement beams for 451 and 452 are normally tested at 3, 5, or 7 days of age. If the results are not needed before the end of the 7-day curing period, only one beam break is necessary and should be made at the age of 7 days.

The beams must be tested with the center loading, hydraulic type-testing machine. The load is applied with a hydraulic jack.  The machine scale reading is a direct reading of the modulus of rupture in pounds per square inch (megapascals).

Testing Beams with Center-Loading Hydraulic Type Testing Machine

The hydraulic, center-loading, beam breaker is designed to test 6-inch x 6-inch x 40-inch (152-mm x 152-mm x 1,016-mm) concrete beams.  Two flexural strength tests can be made with each beam.  The breaker shows a direct read out in pounds per square inch (megapascals) directly on the dial.  No charts or conversion tables are needed to change total load to flexural strength, as is the case with other types of beam breakers now in use.  The standard 6-inch x 6-inch (152-mm x 152-mm) beam is the only size beam on which this breaker can be used.

Figure 499.U – Hydraulic Beam Tester in Position on Beam

Figure 499.V – Pressure Gauge Dial

Parts and Accessories

1.        Beam Breaker.

a.        A main frame with two 7-inch (178 mm) channels containing two fixed rollers.

b.        Yoke assembly containing hydraulic ram, pressure gauge with four 1/2-inch (114 mm) dial choker valve located just below the gauge, and center roller.

2.        Accessories.

a.        Carrying Case.

Method of Operation

The flexural strength, in pounds per square inch (megapascals) is obtained is in the following manner:

1.        Prepare the beam for testing by rotating it 90 degrees around the long axis from the position in which it was molded. The original top of the beam should now be on the side and the top and bottom of the beam should be the sides of the beam that were originally against the mold. Raise the beam at least 2 inches (50 mm) off the ground by supporting each end. This allows clearance under the beam so that the center pin from the yoke of the beam breaker can be inserted under the beam.

2.        Lift the breaker from the carrying case and set it on the beam to be tested with the two fixed rollers resting firmly on the surface and one of them about 1 inch (25 mm) from the end.

3.        Remove the center roller, a 1-inch (25 mm) round pin from the two U-shaped clevises by sliding it out.  The yoke assembly, containing the ram, pressure gauge, and choker valve now can be pivoted into the vertical (operating) position with the clevises extending below the bottom surface of the beam.  There is a stop on one side of the main frame with which the yoke assembly hinge-bracket must be in contact in order for the yoke assembly to be in the vertical position.  Return the pin to the clevises. The yoke pin should now be underneath the beam.

4.        Close the choker valve (the valve just below the gauge dial) by turning it in a clockwise direction, when facing the dial, and open it approximately one-fourth of a turn. Once this valve is adjusted to the position of one-fourth turn open, this procedure does not need to be repeated with each test but only if the valve has been inadvertently turned to some other position. Do not attempt to operate the beam breaker with the choker value closed.

5.        Close the pump valve by turning the pinned extension valve stem in a clockwise direction.  This valve is located on the right side of the pump when facing the dial and is opened and closed by an extending through the flange of the aluminum channel forming the top of the main frame.  This valve must be closed firmly so that the pump will operate properly.

6.        Adjust the black hand of the gauge to the zero point by turning the knurled brass knob on the side of the gauge housing.

7.        Set the red hand (maximum indicating hand) near zero by turning the knurled brass knob in the middle of the plastic dial cover.

8.        Operate the pump by slow steady stokes until the beam breaks or the specified strength plus 100 psi (1.0 mPa) is reached.  Read the flexural strength, in pounds per square inch (megapascals), as indicated by the red hand. Unless otherwise required by the specifications, discontinue the test at 100 psi (1.0 mPa) over the specified strength in order to avoid unnecessary damage to the beam breaker and note on the report that the test was terminated before failure.

9.        Open the pump valve and the pump plunger will retract so that the center roller can be withdrawn and the broken portions of the beam can be removed.  If additional tests are to be made immediately, repeat the foregoing procedure.

10.     If no more tests are to be made immediately, the yoke assembly should be folded down into the horizontal (carrying) position and the center roller again inserted through the clevises in the preparation for storage.  Then place the beam breaker in the carrying case.

Recording Results

Record the slump, air content, concrete temperature, and concrete yield on the TE-45 or TE-45 Supplement form.  Record all beam tests results on the TE-45 later after they are tested and enter them in SiteManager as detailed in Supplement 1023.

Care and Maintenance of Concrete Testing Equipment

Testing equipment represents a considerable monetary investment by the Department and therefore, it is essential that the equipment be given proper care to avoid damage.  The equipment has been provided for testing purposes and must be used in the appropriately to avoid unnecessary abuse or damage.  Periodic review of test procedures is desirable not only to ensure accurate and uniform testing but to prevent damage by improper use of equipment.

The equipment is subject to wear and will need repair and replacement of parts at times.  When this repair work is needed, the piece of equipment should be sent to the District laboratory at once.  Equipment must be in good working condition in order to provide test results that are representative of the material being tested.   In addition, with the volume of work in progress, it is vital that testing equipment be repaired quickly and returned to the project in order to provide the equipment necessary for job control.  If this cannot be accomplished, the Engineer must make arrangements for temporary use of other equipment rather than omit any required tests.

All equipment must be thoroughly cleaned immediately after use, being especially sure that all concrete and mortar is removed from around gaskets, seals, and moving parts.  Thorough cleaning will prevent build-up of hardened concrete that can affect the operation of the equipment as well as the test results.

Pressure Meter

When the top assembly is removed, it should be placed on a clean surface to prevent damaging the gasket and any earth or fresh concrete from clogging the clamping mechanisms.  All fresh concrete should be removed from all parts of the meter to facilitate its accuracy and continue its efficient service.

Volumetric Air Meter

The volumetric meter should not be rolled, rocked, or bumped on hardened concrete, stone, or steel.  It should be used on a clean board or sack.  When the top cone is removed, it should be placed on a clean surface to prevent earth or fresh concrete from clogging the springs around the fasteners.  The inside of the glass tube should be kept clean of cement particles so as not to obscure readings.  All fresh concrete should be removed from all parts of the meter to facilitate its accuracy and continue its efficient service.

Chace Air Indicator

When emptying the instrument at the completion of a test, flush out particles of sand from between the glass and cup to prevent damage when removing stopper.  This can be done by holding the indicator with stem end down, finger over stem, and opening and shaking gently. Carefully remove stopper and wash and clean the indicator with clean water.  Keep the equipment in protective container when not in use.  Should the glass be broken, the remainder of the set should be returned to the Laboratory for repair.

Center Loading Hydraulic-Type Beam Testing Machine

This beam breaker is a piece of testing equipment and should be handled and cared for like any other precision instrument.  The following precautionary measures will help keep the breaker in proper operating condition:

1.        Be sure that the choker is open one-fourth turn before applying load.

2.        Do not operate beyond the maximum point indicated on the dial.

3.        Store in the carrying case when not in operation.

4.        Remove curing membrane, rust, etc., from the center roller so that it will fit in the devices easily.

5.        Keep thin film of oil on steel parts to prevent rust.

6.        Make frequent checks for worn places or breaks in the rubber hose. Do not operate the breaker with worn or damaged hose. This beam breaker is actuated by a high-pressure hydraulic system and might be unsafe if operated with worn or damaged parts.

7.        DO NOT ATTEMPT TO REPAIR THE BEAM BREAKER IN THE FIELD. Return the beam breaker to the Laboratory for any repairs or adjustments that may be necessary.

Concrete Mix Adjustments (499.04)

During concrete production and placement, the Contractor is responsible for adjusting the yield of the concrete mix design.  While a contractor and the supplier are responsible for adjustments, the concrete control inspector is responsible for ensuring the Department’s contract is met.  There will be times were the concrete control inspector must validate and therefore understand what affects the yield so that the yield can be maintained within a certain tolerance.  ASTM establishes and industry standard for yield tolerance of ±1.0 percent.

Verifying the Yield

As discussed earlier, the yield of a concrete mix is the volume occupied by the mix.  The concrete is designed to occupy a given volume.  Concrete is batched by weight (not volume) so monitoring the volume (yield) after batching is of extreme importance. Control of yield is the Contractor and supplier responsibility. Verification of yield by the Department is done to check that the truly reflect what has been added or not added into the concrete batch.  

Relative Yield

The term relative yield is used to understand the effects on yield.  The relative yield of a concrete mix is defined as the one cubic yard (one cubic meter) batch weight divided by the one cubic yard (one cubic meter) unit weight of a representative sample of the concrete, as shown in Figure 499.25:

Equation 499.25 – Relative Yield Method 1

Another way to calculate the relative yield is to divide the actual yield by the intended yield, as shown in Equation 499.26:

Equation 499.26 – Relative Yield Method 2

The relative yield is a dimensionless number (it has no units).  When working with relative yield, it is less confusing to include [yd³] or [ft³] ([m³]) in brackets so the units are not mixed.  A relative yield expressed in [yd³] is multiplied by 27 ft³/yd³ to change it to the number of cubic feet [ft³] of relative yield.

A relative yield of less than 1.00 is an under-yield and a relative yield of greater than 1.00 is an over-yield.

Example:

An 8-cubic yard batch of concrete has the following batch weights:

                Coarse Aggregate    13,328 lbs

                Fine Aggregate          9,448 lbs

                Cement                      5,080 lbs

                Water                                         2,400 lbs

                Total Batch Weight                  30,256 lbs

The result of a unit weight test performed on a concrete sample is 141.35 lbs/ft³.  Determine the yield and relative yield of the batch.

First, the yield can be calculated from the data given:

Yield

 (Equation 499.2)

Next, determine the one cubic yard batch weight:

Batch Weight

for 1 yd.

(Equation 499.2)

The unit weight for one cubic yard is determined using the unit weight given:

                Unit Weight for 1 yd³ = (141.35 lbs/ft³) x (27 ft³/yd³) = 3816.45 lbs/yd³

Note that in the above calculation, the 1-cubic yard unit weight is determined by multiplying the 1-cubic foot unit weight by the conversion factor of 27 ft³/yd³.  This converts the unit weight to lbs/yd³ instead of lbs/ft³.

Now, the relative yield can be determined by the use of Equation 499.25 as follows:

Relative Yield

(Equation 499.25)

Another way to calculate the relative yield is to divide the actual yield by the intended yield (Equation 499.27):

Relative Yield

(Equation 499.26)

In the above calculation, the actual yield (in cubic feet) is divided by a conversion factor of 27 ft³/yd³ to convert the actual yield in cubic feet to cubic yards.

The relative yield expressed in cubic feet is:

Relative Yield          = 0.991 [yd³] x 27 ft³/yd³       

                                                = 26.76 [ft³]           

In the above example, the relative yield is less than 1.000 [yd³] or 27.00 [ft³], therefore, there is an under-yield.  The amount of the under-yield can be determined as follows:

Under-Yield            = 0.991 – 1.00        

                                                = -0.009 [yd³]        

or

Under-Yield            = 26.76 – 27.00      

                                                = - 0.24 [ft³]           

The negative sign indicated that there is an under-yield.  A positive number would have indicated an over-yield.

The under-yield expressed as a percent is determined by multiplying the amount of the under-yield in decimal form by 100 percent as follows:

Under-yield (%)      = -0.009 x 100 %   

                                                = -0.9 % 

Cement or Cementatious Factor

The cement factor is defined as the weight of cement in a cubic yard (cubic meter) of concrete, based on the concrete’s yield.  The cement factor is expressed as the number of pounds of cement per cubic yard (kilograms of cement per cubic meter).

If the concrete is over-yielding, the cement that was batched into the load is spread over a greater volume of concrete than intended by the mix design.  If this happens, the cement factor is less per cubic yard (cubic meter) than intended.  The opposite is true if there is an under-yield.  In the case of an under-yield situation, the cement that was batched into the load is concentrated into less volume than for which it was designed.  In this situation, the cement factor is greater per cubic yard (cubic meter) than was intended by the design.

The relative yield is used to determine the cement factor as shown in Equations 499.27 and 499.27M:

Equation 499.27 – Cement Factor

Equation 499.27M – Cement Factor (metric)

The cement weight in the above equations is the amount of cement intended to be in a cubic yard (cubic meter) of concrete.

In the above example, the relative yield was 0.991 and the cement content was 635 lbs per cubic yard (5080 lbs / 8 cubic yards = 635 lbs/yd³), therefore, the cement factor is:

(Equation 499.27)

As shown by the above calculation, the under- yield resulted in a cement factor of 641 lbs per cubic yard instead of 635 lbs per cubic yard.

The cement factor can influence the strength of the concrete. An excessive over-yield results in less cement per cubic yard (cubic meter), as the cement factor will be less than intended.  This could result in less strength than expected from the batch.  An excessive under- yield results in a higher cement factor, and therefore, higher strength than anticipated.  There should not be a noticeable effect on strength if the yield is maintained within 1 percent of the design as required by 499.03 of the specifications.

Air Content Effects on Yield

Air content in concrete has a significant effect on the yield.  Air content in a concrete mix has no weight but does contribute volume.  The air content used in the design is the target air content.  At the target air content, the yield should be within the tolerance of ±1.0 percent as specified in 499.03 of the specifications. 

If the Inspector determines the yield problem is the result of an air content that is higher or lower than the target air content before a mix adjustment is made.  There is a way to compute what the relative yield of a concrete batch would be at an air content that is different from the tested air content.  

First, determine the relative yield and the tested air content of a concrete sample.  Next, compute the non-air portion of the mix.  The non-air portion of the mix is the volume of all of the component materials except air.  This value is determined by multiplying the actual relative yield by the actual non-air decimal.  Once the non-air volume is determined, the relative yield at any other air content can be calculated.  Equation 499.29 is used to determine the relative yield at a different “target air” content:

Relative Yield at a Target Air =

Equation 499.28 – Relative Yield at Target Air

Where:

                RY actual = actual relative yield (yd³)

                NAD actual = actual non-air decimal

                NAD target = target non-air decimal

Example:

As an example, the relative yield of a concrete mix is found to be 0.974 [yd³] and there is 4.2% percent air content.  What is the relative yield at 6% percent air content?

The actual non-air portion of the mix at 4.2% percent air content is 95.8 percent (100% - 4.2% = 95.8%) of the total volume.  The actual non-air decimal then is 0.958 (95.8%).  To calculate the relative yield at 6% percent air, the target non-air portion of the mix would be 94 percent (100% - 6 % = 94 %) of the total volume. The target non-air decimal is 0.94 in decimal form.  Now the relative yield at 6 percent% air can be calculated as follows:

Equation 499.28

The calculations show that by increasing the air content of the concrete from 4.2% percent air to 6% percent air, the relative yield changes from 0.974 [yd³] to 0.993 [yd³].    The Inspector should not adjust the batch weights to correct the yield to within ±1.0 %percent but should direct the Contractor to increase the air content percentage in subsequent concrete loads to bring the concrete to the proper yield.

The air content affects the unit weight of the concrete. When the air content percentage in the concrete is increased, the unit weight of the concrete is decreased.  This is due to the increased volume of air bubbles within the mortal fraction of the concrete volume.  This lower unit weight results in raising the yield higher than it was at the lower air content, assuming the batch weights are identical.  When the yield is calculated, the same batch weight is divided by a lower unit weight, so the yield increases.

Adjusting Yield

The concrete control inspector should not make adjustments in the mix design.  Mix design adjustments are the responsibility of the Contractor and the supplier.  If during quality assurance inspections the concrete control inspector finds the concrete is out of tolerance, notify the Contractor and require adjustments be made before acceptance of the concrete.  

Mix design adjustments should not be made every time high or low air content affects the yield, because when the air content is at the target air, the yield will be off.  The specifications typically allow air content to deviate ±2 percent% from the target air content.  For all Department mix designs, the desired yield should be established at the target air content.  Once the mix design is adjusted to yield properly at the target air content, future mix design adjustments are rarely needed.

To adjust the mix design to correct the yield, the adjustment is always made in the aggregate weight by adding or subtracting material.  The adjustment is made by volume, and the volume of the adjustment is converted to a weight of coarse and fine aggregate proportionately.

Modifying Mix Designs

It may be necessary to modify an existing concrete mix design while under production.  The Contractor accepted JMF mix designs are designed to produce one cubic yard or 27 cubic feet per cubic yard (one cubic meter) of concrete.  During production, it may be necessary to change the quantity of a material in the mix due to specific gravity changes for that material.   Adjustments for a change in the actual aggregate sources are not allowed unless the new the JMF has been modified to show the new aggregate and the JMF has been approved.

The yield must be maintained if a component material’s specific gravity is changed.  Specific gravity changes do not change the volume of the material in the mix design, but they will change the weight of the material in the mix design.

If of one material is changed, then the volume of another material must be adjusted to compensate for the volume change made.  If any volume is added or removed from the design volume, an equivalent volume must be removed or added respectively to maintain the yield.

Modifying Aggregate Proportions

Section 499.04 does provide for the Contractor to adjust SSD aggregate proportions up to 100 lbs (44 kg) per cubic yard (cubic meter).  This may be necessary to improve the finishing characteristics of the concrete, to ensure a workable mix within the slump range, or to control the yield.  These modifications made in the aggregate proportions are not to change the total weight of aggregate specified per cubic yard (cubic meter), except for the following reasons.

1.        To correct the SSD aggregate weights to compensate for the moisture contained in the aggregates at the time they are used.

2.        If it is not possible to make concrete of the proper consistency without exceeding the specified water-cement ratio, the Contractor must either use a water-reducing admixture or increase the cement content.  If cement is added to the concrete, the absolute volume of aggregate must be adjusted by the amount of cement absolute volume added.  There is no compensation to the Contractor for the use of an admixture or additional cement.

3.        If at any time the specific gravity of the aggregate being used changes by more than 0.02 from the specific gravity specified in the JMF, the design weights need to be adjusted to conform to the new specific gravity.

4.        To adjust the batch weights based on the yield determined from field tests at the work site.  Maintain the cement content within ±1 percent and do not exceed the water-cement ratio specified.

It may be necessary or required by specifications to add an intermediate-size coarse aggregate.  If it is necessary to add a quantity of aggregate, the yield will change unless an adjustment is made to offset the volume added to the concrete.  The same thing is true if it is necessary to remove a component material from the original mix design.  If any volume of material is removed, the same volume must be added to the concrete mix to adjust the yield for the volume removed.  The following example illustrates how a volume change is made.

Example:

To improve the finishing characteristics of a Class QC 2 concrete using limestone coarse aggregate, it is decided to remove 100 lbs of coarse aggregate from the following original SSD mix design:

                Cement                                    700 lbs

                Coarse Aggregate                    1530 lbs, (Specific Gravity = 2.65)

                Fine Aggregate                        1260 lbs, (Specific Gravity = 2.62)

                Water                                       350 lbs

What is the new SSD mix design if 100 lbs of coarse aggregate is removed?   Make the volume adjustment by adding fine aggregate without affecting the yield of the mix.

The new amount of coarse aggregate is 1,430 lbs (1,530 – 100 = 1,430).  The absolute volume of 100 lbs of this coarse aggregate removed from the concrete is:

Absolute Volume

(Equation 499.4)

Since 100 lbs of coarse aggregate is removed, the volume is decreased by 0.60 ft³.  In order to maintain the yield, 0.60 ft³ of fine aggregate must be added.  This volume is used to calculate the weight of fine aggregate necessary to be added to maintain the original yield as follows:

      Addition of Fine Aggregate

(Equation 499.6)

 = 98 lbs

This calculation shows that 98 lbs of fine aggregate (of specific gravity 2.62) must be added to offset the 100 lbs of coarse aggregate (of specific gravity 2.65) removed from the mix design. The new fine aggregate SSD design weight becomes 1,358 lbs (1,260 + 98 = 1,358).

Therefore, the following is the new SSD mix design:

                Cement                                    700 lbs

                Coarse Aggregate                    1,430 lbs, Specific Gravity = 2.65

                Fine Aggregate                        1,358 lbs, Specific Gravity = 2.62

                Water                                       350 lbs

Note that the specific gravities of the coarse and fine aggregates are similar; therefore, the difference in the weight between the coarse aggregate removed and the fine aggregate added is only 2 lbs.

Modifying the Slump

It may be necessary to increase the slump of the concrete by adding water to the mix design, or reduce the slump by removing water from the mix design.  With the addition or removal of water from a mix design, both the water-cement ratio and the yield will change. 

If the concrete in use is being batched at the maximum water-cement ratio, no additional water is permitted, or the water-cement ratio would be exceeded.  It may be necessary to add cement, to maintain the water-cement ratio. Only allow this type of modification after approval of the Engineer.  If allowed, the follow example defines the method to determine the additional cement.

Example:

A concrete mix has a water-cement ratio of 0.50 and the slump is 2 inches at the maximum allowable water.  It is decided to add 10 lbs of water to the mix design to increase the slump.  Determine the amount of cement necessary to maintain the 0.50 water-cement ratio.  Determine the amount of volume added due to the addition of the 10 lbs of water and this necessary amount of cement.

Since the water-cement ratio is defined as follows (Equation 499.13):

The following form of Equation 499.13 calculates the weight of cement from the w/cm ratio:

Equation 499.29 – Cement Weight from w/cm Ratio

Therefore, the amount of cement necessary is:

Weight of Cement

(Equation 499.29)

To maintain the yield, a volume adjustment must be made for both the 10 lbs of water and the 20 lbs of cement as follows:

Volume of Water Added

(Equation 499.4)

Volume of Cement Added

(Equation 499.4)

The total added volume due to the water and cement is 0.26 ft ³ (0.16 + 0.10 = 0.26) in this example.  In order to maintain the yield, 0.26 ft³ of aggregate must be removed from the design.  Aggregate removed will be proportional to the aggregate in the mix.  If the coarse aggregate is 60 percent% and the fine aggregate is 40 percent% (and the specific gravity of the aggregates are the same), the volume of coarse aggregate removed would be 0,60 x  0.26 ft³ = 0.16 ft³.  Fine aggregate would be 0.26 ft³ - 0.16 ft³ = = 0.10 ft³.   

Modification of Aggregate Specific Gravity

If there is specific gravity changes in the aggregates used, the yield of the concrete mix will change.  If there is a specific gravity increase, then the volume occupied by the same weight of aggregate will decrease and there will be an under- yield.  If there is a specific gravity decrease, the volume of the same weight of aggregate increases and the mix will over-yield.

Example:

A concrete mix contains 1,735 lbs of a crushed limestone with specific gravity of 2.65.  The aggregate stockpile is depleted and the Contractor changes to natural gravel coarse aggregate with a 2.57 specific gravity.  Adjust the 1,735 lbs to the new specific gravity and show how this would affect the yield.

Determine the original volume in the mix design:

Original Mix Design Volume

(Equation 499.4)

If the specific gravity changes to 2.57, this same weight of aggregate would have the following absolute volume:

New Mix Volume

(Equation 499.4)

These calculations show that same weight of a lower specific gravity aggregate has a greater volume and would result in an over-yield.  To correct the over-yield the original volume is used to determine how much weight of the new, lower specific gravity aggregate to use:

New Aggregate Weight

(Equation 499.6)

In summary with the lower specific gravity, the weight decreased from 1,735 lbs to 1,683 lbs per cubic yard.

Use Equation 499.30 to calculate a weight adjustment due to a specific gravity change:

 Equation 499.30 – Weight Adjustment due to Specific Gravity Change

Where:

  = Original weight of aggregate (at the original specific gravity)

= Original specific gravity of the aggregate

 = New specific gravity of the aggregate to be used

For the above example, the calculation is as follows:

New Weight = 

(Equation 499.30)

Equipment for Batching and Mixing Concrete (499.05)

Batching Plants (499.05.A)

The various materials for each batch of concrete are proportioned at a batch plant.  Batch plants may be classified as:

1.        Portable or stationary

2.        Manual, semi-automatic, or automatic

3.        One or two stop

4.        Separate or accumulative weighing

These classifications are dependent on the mobility and the method of weighing and discharging.  Batch plants used on the project site usually are portable and may be moved from job to job. They may be manual, semi-automatic, or automatic with the latter two categories most common. If all materials for a batch are discharged at the same point, it is a one-stop plant.  A two-stop plant is a plant where two stops of the truck mixer is required.

Portable plants are moved from site to site to reduce the length of haul to the placing site. Stationary plants usually are used at commercial ready-mix or central-mix plants.  Central-mix plants used for concrete paving are set up at the job site, and, therefore, are portable.

Plants may employ accumulative weighing for the coarse and fine aggregate; however, separate weighing devices must be used for weighing cement.  Accumulative weighing permits the weighing of coarse aggregate and then the fine aggregate, using the same hopper and scale.  The predetermined weights for the two materials are set on the scale for the cut-off.  Cement must be weighed separately on a separate scale and hopper, regardless of how the aggregate is weighed.

For manual plants, each material is weighed and discharged by manually pulling levels to open and close gates.  In semi-automatic plants, these gates are operated through electronic controls to open and close at the touch of a button.  If the electric controls are interlocked, and the completion of one weighing signals the start of next weighing, etc. and the whole cycle, if weighing and discharging is interlocked completely, the plant is classed as automatic.

Automatic plants are coming into widespread use with many being computerized.  Some plants use punched cards which have the weights of the materials represented by holes punched in the card.  The size of the batch is dialed by a selector knob, the punched card is placed into the control panel, and a button is pressed to start the cycle.  Materials for the batch size selected are automatically weighed and discharged.

A system of interlocks prevents a batch from being discharged that does not contain the correct amount of each material.  All automatic plants have this feature.  This prevents incorrect batches in the event that an aggregate bin becomes empty or other trouble develops which would tend to result in incorrect batch weights.  Most automatic plants may be operated manually or semi-automatically, which permits production in case of an electronic failure.

The accuracy of the weighing mechanisms used to weigh each component in the concrete is specified in 499.06.  These weighing tolerances are shown below:

Weighing Tolerances

Item

Weighing Tolerance* (Percent)

Cement

±  0.5

Fly ash

±  0.5

GGBFS

±  0.5

Micro silica

±  0.5

Coarse aggregate

±  0.5

Fine aggregate

±  0.5

Water

±  1.0

Admixtures

±  3.0

* Weighing tolerances apply throughout the range of use.

Prior to use of a concrete plant, make an inspection to assure that all requirements of the specifications are fulfilled and that scales meet the batching tolerances specified.  This inspection includes checking:

1.        Plant bins for adequate partitions to prevent intermingling of materials.

2.        All weighing and metering devices to assure ensure that their accuracy has been attested to within a 12-month period immediately prior to use by one of the following methods:

a.        By a Sealer of Weights and Measures.

b.        By a Scale Servicing Company.

c.        By a Certificate of Performance issued by the National Ready Mixed Concrete Association.

3.        The plant must maintain ten 50-pound (23 kg) standard test weights or the services of a scale servicing company for testing weighing devices for accuracy.  The ten 50-pound (23 kg) test weights must be sealed within a 3-year period by the Ohio Department of Agriculture.  If the service of a scale servicing company is used, these weights will not be required; however, all weights used in testing by the Scale Servicing Company must conform.

4.        Water meters for accuracy.

5.        That a separate weighing device is used for weighing cement.

6.        Admixture dispensers to assure proper dosage will be used.

If a Certificate of Performance has been issued by the National Ready Mixed Concrete Association, the weighing and metering devices will not require checking for accuracy and the concrete batch facilities may be approved.  The certification from the National Ready Mixed Concrete Association must be within a 6-month period prior to use and must certify that the plant's weighing and metering devices do meet 499 batching tolerances.

Plant bins are checked for holes in partitions and to see that separator plates are extended high enough to prevent spillage of materials when the bins are charged.  Accumulation of aggregate in the corners must be avoided.  Any evidence of this should be called to the attention of the plant operator and corrected immediately.

The test weights must have a seal indicating that they have been checked by the Ohio Department of Agriculture or some other acceptable agency and certified for accuracy.  These seals must be renewed every 3 years.  Each scale must be checked with test weights through the range in which it is to be used.  Should a scale be used to weigh the aggregate accumulatively, say for example, totaling 13,356 pounds (6058 kg), it must be checked through 13,400 pounds (6078 kg).  This will require that the weights be attached and the scale checked for 500 pounds (227 kg), then the weights removed, 500 pounds (227 kg) of aggregate added, and the scale checked again with the weights, this time to 1,000 pounds (454 kg).  This process is repeated until 13,400 pounds (6078 kg), or the total range, actually being used, is reached.  All scales shall be checked within the 12-month period immediately prior to use.

If a scales servicing company is employed by the producer to check and adjust the scales, the test weights used may range up to 1,000 pounds (454 kg).  When these test weights are used, the scales should be checked by adding the weights to the scale and checking the scale as outlined in the previous paragraph.  All weights used by the Scale Servicing Company must be sealed every 3 years by the Ohio Department of Agriculture.

A weight increment greater than 500 pounds (227 kg) may be used to check the batch plant scales in the lower range of use when large batches of concrete will be produced.  However, smaller increments will be necessary when nearing the limit of use.  This situation occurs for a paving operation with a central mix plant that consistently producing produces larger batches.  On the other hand, when the batch plant will be produces small or varied size batches of concrete, a maximum of 500-pound (227 kg) increments should be maintained.  The testing must be for the range of use for the scale, and tolerances mentioned previously should be maintained. Adjustments should be made when necessary.

Water meters also must be checked and calibrated prior to use.  Whether the water is metered by weight or by volume, the amount of water required for one cubic yard (cubic meter) of central mix, or transit mix concrete, or one batch of site mix concrete, should be metered and carefully collected for immediate weighing.  The weight of the collected water must be within 1.0 percent of the weight indicated on the meter if the water is weighed.  If the water is metered by volume, the water should be collected and weighed, then divided by 8.32 pounds per gallon (1 kg per liter). The volume in gallons (liters), thus obtained, must be within 1.0 percent of the volume metered.  Variations outside the tolerance must be corrected and the water meter rechecked until it is within the required accuracy.

Admixture dispensers are checked by actually discharging a given amount of admixture to verify the accuracy of the unit.  Admixture dispensers must be accurate to within 3.0 percent of the indicated amount. 

Admixtures held over from the previous year should be either replaced or retested by the admixture manufacturer.  Agitation of the old admixture may bring the materials within specification but it should be tested and checked.

All checks made prior to starting production for each construction season must be documented.  Checks made during concrete production must be noted on the TE-45 Report.  Weighing and dispensing devices must be tested as often as the Engineer deems necessary to assure ensure their continued accuracy.

During the batching operation, the Inspector should occasionally observe the amounts of the materials being weighed to ensure that proportioning complies with the mix design.  Therefore, the Inspector must know the various weights for the volumes being used as well as be familiar with plant components.  Checks must be made to determine that the indicator dials return to zero when the batch is discharged.  This is especially important for the cement scale.  If the scale does not return to zero, it is an indication that material is building up or hanging up in the hopper.  This material must be removed and the dial adjusted to read zero.  Any scales not zeroing properly must be repaired.

Concrete Mixers (499.05.B and 499.08)

Transit mix trucks are used to haul plastic concrete batches to the concreting site.  The concrete may be mixed at the plant and agitated during hauling, agitated during hauling and mixed at the point of use, or mixed in transit if it can be shown that mixing is accomplished during transit.  Transit mixers also may be used to haul mixed or partially-mixed central mix concrete.  When used for hauling concrete that has been mixed completely in a central mixer, the mixer is operated at agitation speed.  If the concrete is only partially mixed, all materials must be mixed for at least 30 seconds in a stationary mixer and then mixed in the transit mixer for no less than 50 revolutions at mixing speed.  This latter mixing is known as shrink mixing.

Central mix concrete may be hauled in truck agitators, commonly known as dumpcrete trucks, or trucks having bodies without agitation.  Non-agitating equipment must have smooth, mortar-tight bodies capable of discharging concrete at a satisfactorily controlled rate.  If dump trucks are used for non-agitation hauling, they must have smooth bodies with rounded corners and be free of internal ribs.

Mixers and agitators must meet certain sections of AASHTO M 157.  Section 499.05 B. requires conformance with AASHTO M 157 Sections 10, 11.2, 11.5, and 11.6 except that the Department will allow mechanical counters.  These sections are reprinted at the end of this section in a section entitled AASHTO M 157.

Handling, Measuring and Batching Materials (499.06)

Stockpile foundation areas must be cleared of all wooded brush or other debris, and shaped to provide drainage.  The area may be compacted, stabilized, or paved to prevent the existing ground from infiltrating into the bottom of the pile.  If the aggregate is placed directly on the ground, the bottom foot of aggregate must not be removed until final clean-up, and any material that has become contaminated must be reprocessed to meet specifications before use.

Where one stockpile adjoins another of a different size material, a substantial bulkhead or divider of sufficient length and height must be placed between the two to prevent intermingling of the different sizes.  Intermingling of stockpiles must not be tolerated.

Aggregate must be dumped directly on the prepared stockpile as near to its final location as possible without additional handling.  After the first layer is placed directly on the foundation, trucks must unload at the outside edge of the pile and the material moved into position on the succeeding layers.  A crane with a bucket is ideal for picking up the aggregate and placing it on top of the material in place.  Exercise care to deposit each bucket in a manner that prevents the aggregate from rolling and segregating.  Therefore, the bucket should not be high in the air when the aggregate is released.

Front-end loaders are satisfactory to build a stockpile provided they stay off the stockpile (unless they are equipped with rubber tires) and if care is exercised to place each scoop load in a manner to avoid segregation.  Equipment having steel treads must not be used on coarse aggregate stockpiles, nor should any equipment be permitted to push, shove, or roll coarse aggregate as segregation may result.  If the Contractor uses equipment that appears to be causing segregation, additional tests must be run, and, if there is a variance from specification gradation requirements, the use of the equipment must be discontinued.

Sand may be dumped directly on the prepared foundation for the bottom layer and succeeding layers placed by crane with bucket, by front-end loader, or by dozer.

Equipment that operates on stockpiles must not be permitted to move on and off the stockpile unless the foundation is stabilized or paved to prevent tracking of foundation material onto the stockpile.   The tracking of foreign material onto stockpiles, (while stockpiling aggregate or removing aggregate from stock piles to charge the concrete plant, can result in mud balls in the concrete.

Coarse aggregate is absorptive and will attract and absorb mixing water when used in a dry condition in concrete.  This absorption of water needed for workability can result in a rapid slump loss when the aggregate is dry.  Such a slump loss usually results in finishing and texturing problems.  Coarse and fine aggregate is required by 499.04 to be maintained with a uniform moisture content.

A moisture test must be made to determine the moisture content for use in adjusting the batch weights and the mixing water.  When the actual moisture content of the fine and coarse aggregate is compared with the absorption of the aggregate, the Inspector will know if the aggregate is in a damp or saturated condition.  Moisture contents greater than absorption indicate saturation, while those less indicate a damp condition.

Batching Coarse Aggregate

Segregation is possible when withdrawing coarse aggregate from stockpiles for charging into the plant bins, unless care is exercised.  Cranes with buckets, and front-end loaders, are satisfactory for this operation, provided the aggregate is handled in such a manner to avoid segregation.  Any operation that results in excessive segregation, such as sliding or rolling, must not be permitted.

Batching Fine Aggregate

The use of a dozer is satisfactory for moving fine aggregate from large stockpiles to a conveyor for the transfer to the plant bins.  With a dozer, material from the same level in the stockpile is pushed into a hopper feeding the conveyor.  Being from the same level, the sand has the same moisture content and uniformity is maintained.

Fine aggregate will be handled in such a manner that the moisture content will be reasonably uniform for each day's production. Whenever the moisture content is suspect for a given stockpile, the stockpile should be rotated or mixed prior to charging the hopper feeding the conveyor.  This will assure uniformity of the moisture content.

Batching Cement and Cementatious Materials

Cement is usually fed by gravity from storage silos to weigh hoppers.  Cement may also be pumped or blown from an auxiliary storage silo to a cement bin in the plant.

Batching Water

Water may be pumped into a measured storage tank, having the capacity required for the batch, where it flows by gravity into the central mixer or transit mixer.  Water meters are in common use and can measure the water accurately per batch by volume or by weight.  Water measuring devices should be checked and adjusted to an accuracy of 1 percent.

Batching Tolerances (499.07)

The batching tolerances are specified in 499.07 and are shown on the following table:

Batching Tolerances

Item

Batching Tolerance (Percent)

Cement

± 1.0

Fly ash

±  1.0

GGBFS

±  1.0

Micro silica

±  1.0

Coarse aggregate

±  2.0

Fine aggregate

±  2.0

Water

±  1.0

Admixtures

±  3.0

Batching tolerances are different from the weighing tolerances.  Weighing tolerances apply to the scales that are used to weigh the individual components of the concrete mix.  Batching tolerances apply to the batching process.  For instance, a 10- cubic yard load of Class QC 1 concrete requires 6,000 lbs of cement.  During the process of weighing this amount of cement into the cement weigh hopper, it sometimes is not possible to stop the cement flow exactly at 6,000 lbs.  The plant operator should be shooting for 6,000 lbs but is permitted a tolerance of 1.0 from this amount.  Therefore, for this amount of cement, the variance can be anywhere from 5,940 lbs to 6,060 lbs.

Batch Plant Tickets (499.07)

A concrete batch ticket must be furnished with each load of concrete delivered to the project.  This ticket will be computer generated.  Look at 499.07 for the required information on each ticket of delivered concrete that certifies the ingredients in the load as well as other required data:

The Contractor must provide additional information with the first load of concrete delivered to each project for each JMF.   The following information must be provided either on the batch ticket or as a separate computer generated (or hand written) form and attached to the batch ticket.

It is a contract requirement that the above information be provided by the Contractor.  If a Contractor is purchasing concrete from a ready-mix concrete supplier, it is the Contractor’s responsibility to ensure compliance even if it means putting a person at the plant to provide the required information.  If the information is not provided as specified, the concrete is not to be accepted.

Mixing Concrete (499.08)

Concrete is to be mixed in either a central mixing plant or by a truck mixer.

Classifications of Concrete Mixers

Concrete mixers are classed as central mixers or transit mixers.  Central mixers are stationary and are located at the batch plant where they are charged directly from the plant.  Mixed batches from central mix plant may be transported to the placing site in dumpcrete trucks, dump trucks, or transit mix trucks.  Transit mixers are charged directly from the batch plant and mixed in truck-mounted mixers at the plant or at the job site.

Central and Transit Mixing

For central mixing and transit mixing, the proportioned materials are charged directly into the mixer from the weigh hoppers.  Caution must be observed, especially with transit mixers having narrow openings, that materials are not spilled during the charging of the mixers.  Usually it will be necessary to feed the batch gradually from the weigh hoppers into the transit mixers to avoid spillage.  The common practice is to revolve the mixer at high speed during charging to aid material entry into the mixer and avoid clogging of the intake opening.

Pre-blending of materials, prior to or during charging of the mixer, plays an important role in obtaining proper mixing. This pre-blending or pre-mixing may be accomplished by depositing materials onto the charging belt in such a manner that all materials enter the drum at the same time or by discharging all materials directly into the mixer simultaneously rather than separately. If the plant capacity is limited and the entire batch cannot be weighed into the weigh hopper in one operation, smaller complete batches should be required rather than weighing and discharging each ingredient independently. Proper mixing will not be obtained in the minimum mixing time if materials are charged separately; therefore, this method must not be tolerated.

Most central mix plants are equipped with a "slump meter" which provides the operator a control of concrete consistency. These meters indicate concrete consistency indirectly by measuring the current or amperage being drawn by the motor that drives the mixer. The mixer operator maintains a predetermined amperage by adjusting the amount of mixing water. The result is uniform consistency between batches.

Mixers and agitators shall conform to paragraphs 10, 11.2, 11.5, and 11.6 of AASHTO M 157, except that mechanical counters are permitted. A copy of these paragraphs of AASHTO M 157 is contained in this manual.

Generally, water is started into mixers first and is charged at such a rate that it will not cease until all other ingredients are in the mixer.  In this manner, water is present initially for mixing material during the charging period and provides a washing action around the drum opening after all the dry materials have entered.

Air-entraining agents and water-reducing set retarders are the most common admixtures for concrete.  It is very important that these admixtures do not become blended or mixed in any manner prior to the actual mixing of the concrete.  Any mixing of the two could cause plugging of the supply lines.  Also, the effectiveness of either or both of the additives may be reduced.  To avoid any problem, they should be introduced into the batch separately.

Mixing Concrete (499.08)

The minimum mixing time for central mixers is 60 seconds, beginning when all the materials are in the drum and ending when discharge begins.  Transit mixers must operate at the rate of rotation stated by the manufacturer as mixing speed, for no less than 70 revolutions.  Checks must be made for compliance with these mixing requirements and the results recorded on the appropriate project documents.

Checks made of mixing time for central mixers are the responsibility of the concrete control Inspector.  At least once a day (more often if possible), a check must be made and recorded on the concrete Inspector's daily report.  The counter reading on transit mixers before and after mixing must be noted and recorded.  The rate of rotation must also be checked. The initial counter reading and number of revolutions at mixing speed are recorded.  The Contractor is responsible for ensuring proper mixing of all batches.  Any deficiencies must be called to the Contractor’s attention.

If possible, for large quantity-critical usage concrete, the Engineer should periodically check the mixing operation at the plant to ensure compliance with specified mixing requirements.  Counter readings and rate of rotation are noted and recorded as described above.  Excessive speed of rotation may cause inadequate mixing.  Centrifugal force causes the materials to cling to the drum rather than be mixed by being picked up and dropped repeatedly by the mixer blades.  The Department's interpretation of mixing speed is the speed (called “mixing speed”) that is noted on the metal plate required on every truck mixer.  When there is an overlap of agitating speed and mixing speed, only the rate of rotation in excess of agitation is considered as mixing speed.  Therefore, the Inspector should examine the metal plate on each truck for the capacity and the rate of mixing.  Trucks that have no metal plate are not permitted for state work. 

If for some reason it is not practical to mix with transit mixers at the plant, the mixing may be done at the site in the presence of a Contractor’s quality control personnel or the concrete control inspector.  If the mixing is done on site, the Contractor will document this for the Department on a TE-45 form. Whether mixing is accomplished at the plant or the site, transit mixers shall rotate at agitation speed while in transit.

If mixing in transit is requested by the ready mix producer, the producer must show that the mixers can and do revolve at a rate in excess of the range for agitation, indicated on the metal rating plate attached to the mixer. Use of counters listing the number of revolutions at agitation speed and the number of revolutions in excess of the agitation range separately will be adequate proof.  The Inspector must record both counter readings when counters of this type are used.

The metal rating plate indicates a range for agitation speed and a range for mixing speed. Normally there is an overlap of the two.  For example, agitation speed may be listed from 2 to 6 revolutions per minute, while mixing speed may be from 4 to 12 rpm.  To qualify as mixing speed in such instance, the mixer shall rotate at 7 rpm (next higher over agitation speed).  At this rate, 10 minutes of mixing would be required for the required 70 revolutions.

The Contractor must ensure that the temperature of the plastic concrete does not exceed 95 ºF (35 ºC) until it is placed in the work.  During hot weather, it may be necessary to use ice in the mixing water or to put sprinklers on aggregate piles to lower the concrete temperature.

Transporting Concrete

The time lapse, from the time water is added to the mix until the concrete is discharged into the work, must not exceed 60 minutes except as modified below.  The Inspector in the field must document the time when the concrete is unloaded and ensure that 60 minutes have not been exceeded.  The Contractor may use, at his own expense, an approved water-reducing set retarding admixture or a retarding admixture for any concrete, and the time may be extended an additional 30 minutes (from 60 to 90 minutes).

Use of completed subgrade or base as roadway for transporting materials should be discouraged, except in the case of crossovers or in the case of unusual circumstances, when it is impractical to operate outside the pavement area.  When these unusual conditions exist and equipment is operated on the subgrade or base, increased inspection must focus on these areas to ensure compliance with specification requirements before concrete is placed.  Increased inspection is necessary to avoid displacement of forms, rutting of surface, and variation from crown tolerances.

When hauling units operate on completed pavement that is opened to construction traffic, they must observe the legal load limits.  Generally, dual rear axle units hauling 7 cubic yards (5.4 cubic meters) of concrete are in excess of the legal limit and will not be permitted to operate on the completed pavement when loaded.  If the Contractor desires to haul loads containing more than 7 cubic yards (5.4 cubic meters) of concrete and intends to use portions of the completed pavement for the loaded trucks, the Contractor must submit the necessary data to show that the loaded trucks are within legal limits.  This data must be submitted to the District office for review.

Periodic inspection must be made of all hauling units.  Items to be checked include:

1.        Do not permit build-up of hardened concrete or cement.

2.        Mixing blades of transit mix trucks should be in working order.

3.        Revolution counters on transit mix trucks must be in working order.

4.        Wash water in the drum of transit mix trucks should be discharged from the mixers before recharging unless the water is metered accurately by a water meter on the transit mixer and results in uniformly consistent concrete.

Concrete Testing Reports

When the Department is performing acceptance testing, the Concrete Inspector's Daily Report, Form TE-45 and/or the SiteManager Test Screens, must be filled out completely for each class of concrete used each day or at the frequency required to meet the sampling requirements. 

The Engineer may determine if the quantity of concrete for the day is small quantity (generally less than 50 cubic yards [38 cubic meters] of concrete is used).  The TE-45 and SiteManager test screens would not be required but a SiteManager sample would still need to be completed.  It is still recommended that some testing be performed on small quantity samples, such as air content, to ensure durability.  The test result can be recorded in remarks.

Sample SiteManager TE-45 forms are shown in Figures 499.D and 499.E.  The Inspector may choose to fill out a SiteManager samples and the two test screens instead of a TE45. 

1.        PCC INSPECTOR DAILY REPORT TE45 PART 1 – BATCH WT

2.        PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS

The SiteManager TE-45 is filled out or the SiteManager Test Screens are filled out for each class of concrete used each day. Reports are numbered consecutively for each day when concrete is used, but numbered reports are kept separate for each class of concrete. 

Figure 499.W – Form SiteManager TE-45, Concrete Inspector's Daily Report 

The worksheet above that matches input information for the SiteManager Test Screen [PCC INSPECTOR DAILY REPORT TE45 PART 1 – BATCH WT] is available on the OMM website at:

Site Manager TE Forms - All Documents

The following are instructions for filling out the TE-45 form part 499D.

1.        SAMPLE ID – The Sample ID number is a computer-generated number. This number is generated by SiteManager when data is entered onto the Sample screen. The number is used to refer to the TE-45 and any cylinder and/or beam specimens made that day.

2.        JMF – The JMF space on the form is for the Job Mix Formula Number assigned to the concrete being produced and tested.  The JMF is a list of the materials that are in the mix and should be provided by the Ready Mix producer supplying the concrete.   The JMF can be verified by going to SiteManager icon , then , and then,  to look up the Concrete JMF’s.

3.        MATERIAL CODE - The Material Code section of the TE-45 form is a number assigned to the type of concrete represented by the sample. These codes are available on the JMF in SiteManager.

4.        ALT CONTRACT ID – SiteManager term for project number.

5.        P/S CODE – This is the Producer/Supplier code.  In this case, it is the code for the Ready Mixed Concrete Company.  This number can be found in SiteManager by going to the JMF screen. 

6.        DATE MADE - This is the date that the concrete is made.

7.        LOCATION - Location of Sample C, also note CLASS OF CONCRETE - The class of concrete to be used on any given item should be determined from the plans.  Just place the name of the class in this box.

8.        CEMENT P/S – Name on first ticket of each day and compared to JMF for QC mixes.  Actual producer supplier code can be found in the JMF or SiteManager icon .

a.        CEMENT - Look on the approved list on the Materials Management website under S 1028 - Cement Certified List.  Make sure to use the code for a MFG PLANT and not a TERMINAL Location. The MFG PLANT location should be on the Bill of Lading for the cement

9.        FLY ASH P/S – Name on first ticket of each day and compared to JMF for QC mixes.  Actual producer supplier code can be found in the JMF or SiteManager icon .

a.         FLY ASH - Look on the approved list on the Materials Management website under S 1026 - Fly Ash Certification List.

10.     GGBF SLAG P/S – Name on first ticket of each day and compared to JMF for QC mixes. Actual producer supplier code can be found in the JMF or SiteManager icon .

a.        GGBF SLAG - Acceptable sources of this material can be found in the ISRC screen of SiteManager. Use material code 37603 for GRADE 100 material and 37604 for GRADE 120 material.

11.     MICRO SI P/S – Name on first ticket of each day and compared to JMF for QC mixes.  Actual producer supplier code can be found in the JMF or SiteManager icon .

a.        MICRO SILICA - Acceptable sources of this material can be found in the ISRC screen of SiteManager. Use material code 37601 for POWDER material and 37601S for SLURRY material.

12.     AEA – Company and brand name on first ticket of each day.  Approved types can be checked on the QPL list. 

13.     ADMIX 1 – Company and brand name on first ticket of each day. Approved types can be checked on the QPL list.

14.     ADMIX 2 – Company and brand name on first ticket of each day. Approved types can be checked on the QPL list.

15.     ADMIX 3 – Company and brand name on first ticket of each day. Approved types can be checked on the QPL list.

16.     ADMIX 4 – Company and brand name on first ticket of each day. Approved types can be checked on the QPL list.

17.     LOT/SUBLOT – If QC/QA concrete with sublots – record the number of the sublot and lot you are testing.

18.     TEST QUANTITY – The space is to show how many cubic yards (cubic meters) of concrete the TE-45 test represents. The space shows how much concrete was produced during the day the report represents.

19.     BATCH TK# – The number of the on the batch ticket for the concrete being tested.

20.     CEMENT WT – Batched ticket cement weight for a cubic yard (cubic meter).

21.     FLY ASH WT – Batched ticket fly ash weight for a cubic yard (cubic meter).

22.     GGBF SLAG WT – Batched ticket ggbf slag weight for a cubic yard (cubic meter).

23.     MICRO SI WT – Batched ticket micro silica weight for a cubic yard (cubic meter).

FINE AGGREGATE

24.     FA BATCH WT – Reported batch weight – can be worked per cubic yard.

25.     FA FREE MOISTURE % – Percent reported on ticket – absorption for the aggregate. 

Aggregate absorptions are posted on OMM website on aggregate information page:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Materials/Pages/AggregateInformation.aspx

26.     FA SSD WT – Weight with water absorbed.  See Example 2 below.

27.     CA1 BATCH WT – Reported batch weight – can be worked per cubic yard.

28.     CA1 FREE MOISTURE % – Percent reported on ticket – absorption for the aggregate. 

Aggregate absorptions are posted on OMM website on aggregate information page:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Materials/Pages/AggregateInformation.aspx

29.     CA1 SSD WT – Weight with water absorbed.  See Example 2 below.

30.     FA SSD WT – Weight with water absorbed.  See Example 2 below.

31.     A1 BATCH WT – Reported batch weight – can be worked per cubic yard.

32.     A1 FREE MOISTURE % – Percent reported on ticket – absorption for the aggregate. 

Aggregate absorptions are posted on OMM website on aggregate information page:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Materials/Pages/AggregateInformation.aspx

33.     A1 SSD WT – Weight with water absorbed.  See Example 2 below.

34.     BATCH WATER (lbs) – Water batch according to Batch Ticket.

35.     FIELD WATER ADDED (lbs) = Water added by truck tank meter.

36.     W/CM RATIO = Total water divided by total cement fly ash etc.

Example 1:

1.        CORRECTED SSD WEIGHT (for Sp. Gr) - This is the SSD design weight of the aggregates adjusted for specific gravity.  This is calculated by multiplying the SPECIFIED SSD WEIGHT by the actual SSD specific gravity and dividing by the design specific gravity.

(Equation 499.3)

Where:

 = Design Weight (SSD) from the appropriate table in 499.03 or 499.04

DSG = Design Specific Gravity from Table 499.A

ASG = Actual SSD Specific Gravity to be used on the project

Adjusted  = Design Weight (SSD) adjusted for the actual aggregate specific gravity

Example 2:  Aggregate Batch Weight – Determine Free Moisture

1.        AGGREGATE QUANTITIES FOR 1 yd3 BATCH WITH CORRECTIONS FOR MOISTURE -.  Each aggregate used should be adjusted for moisture in the following manner:

a.        BATCH WEIGHT - The batch weight is the weight on the ticket corrected to 1 cubic yard.  (Example = 12,400 lbs for 10 yards = 12,400/10 = 1,240 lbs per cubic yard.)

b.        TMCF = The Total Moisture per Cubic Yard (%).  The reported aggregate moisture content for the batch.  IF QUESTIONING THE VALUE FROM THE READY MIXER, ASK HOW MEASURED OR REQUIRE AN AGGREGATE MOISTURE TEST.

c.        AMCF – Absorbed Moisture per Cubic Yard (%).  The Department’s established moisture absorption for the aggregate source.   

                                                               i.      Aggregate absorptions are posted on OMM website on aggregate information page:

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Materials/Pages/AggregateInformation.aspx

FMCF =  

The formula involves changing the two percent’s to a decimal form by moving the decimal two places to the left and adding 1.

FMCF =   1.0467/1.0074 = 1.039

BATCH

WEIGHT

A

SSD weight (B)
A * 1/FMCF

free water

a-b

1382

1382 x 1/1.039 = 1330

1382-1330 = 52

Example 3:

1.        W / CM RATIO – Determine the required Water/Cementitious Ratio (W/Cm) from the contract documents or JMF.

2.        TOTAL CM WEIGHT – Sum the weights of all of the cementitious materials.

3.        TOTAL WATER – Sum the BATCH WATER + the FIELD ADDED WATER + aggregate BATCH WEIGHTS – aggregate SSD WEIGHTS. Equals TOTAL WATER.

4.        WATER IN ADDITIVES - Water in additives needs to be accounted for in the mix water.  This is generally used when the micro silica used is in slurry form.  You would then determine the amount of solid, determine how much is used, and how much of the slurry was water.

Example: A slurry mix is used in a Class QC 3 mix.  There is to be 30 lbs of micro silica in each yd3 of concrete. Determine how much slurry is needed per yd3 and how much water is contributed to the mix if the slurry contains 42 percent micro silica solids.

30 lbs micro ÷ 0.42 = 71.4 lbs of slurry required

71.4 lbs slurry - 30 lbs micro = 41.4 lbs of water added to the mix

BATCH WATER + FIELD WATER ADDED + (FA BATCH WT – FA SSD WT) + (CA BATCH WT – CA SSD WT) + (A1  BATCH WT – A1 SSD WT)

200 lbs + 15 lbs + (1382 – 1330) + (1240 – 1260) + (350 – 335) = 200 + 15 + 52 – 20 + 15 = 262 lbs

TOTAL CM WEIGHT = CEMENT WT + FLY ASH WT + GGBF SLAG WT + MICRO WT. = 350 + 100 + 150 + 20 = 620 lbs

W/CM RATIO = 262/620 = .43

 Figure 499.X – Form SiteManager TE-45, Concrete Inspector's Daily Report

The worksheet above that matches input information for the SiteManager test screen [PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS] is available on the OMM website at:

Site Manager TE Forms - All Documents

The following are instructions for filling out the TE-45 form part 499E.

1.        SAMPLE ID – The Sample ID number is a computer-generated number. This number is generated by SiteManager when data is being entered onto the Sample screen. The number is used to refer to the TE-45 and any cylinder and/or beam specimens made that day.

2.        MATERIAL CODE – The Material Code section of the TE-45 form is a number assigned to the type of concrete represented by the sample. These codes are available on the JMF in SiteManager.

3.        MATERIAL NAME – Note CLASS OF CONCRETE – The class of concrete to be used on any given item should be determined from the plans.  Just place the name of the class in this box.

4.        P/S CODE – This is the Producer/Supplier code.  In this case, it is the code for the Ready Mixed Concrete Company.  This number can be found in SiteManager by going to the JMF screen.

5.        P/S NAME – In this case, it is the name for the Ready Mixed Concrete Company.  This name can be found in SiteManager by going to the JMF screen. 

6.        TEST METHOD – number of the SiteManager test screen.

7.        JMF – The JMF space on the form is for the Job Mix Formula Number assigned to the concrete being produced and tested.  The JMF is a listing of the materials that are in the mix and should be provided by the Ready Mix producer supplying the concrete.   The JMF can be verified by going to SiteManager icon, then , and then  to look up the Concrete JMF’s.

8.        SAMPLER – Your name.

9.        EFFECTIVE DATE 

10.     INTENDED USE – What the concrete is being used for – deck pier column, etc.

11.     CONTROL NUMBER

12.     SAMPLE TYPE – Typically this will be a Control Sample (JCTL), Independent Assurance Sample (IAS), or Information (INF) sample.  Other options for type of sample can be found in SiteManager.

13.     SAMPLE MADE - This is the date that the concrete is made.

14.     ALT CONTRACT ID – SiteManager term for project number.

15.     TEST QUANTITY – The space is to show how many cubic yards (cubic meters) of concrete the TE-45 test represents. The space shows how much concrete was produced during the day the report represents.

16.     AIR % – Test value from running air content test

17.     BATCH TK# – The number of the on the batch ticket for the concrete being tested.

18.     SLUMP IN – Slump test results in inches.

19.     DATE/TIME OF TESTING

20.     BATCH WT LBS

21.     LOCATION OR STATION

22.     PCC TEMP F = Tested temperature of the concrete.

23.     WT/CU FT = Tested weight of the concrete.

24.     CYL or BEAM – Type of strength test sample made.

25.     ACTUAL yield in CUBIC FT – Tested yield.

26.     CYL MODL SIZE – 4 inch x 8 inch?  6 inch x 12 inch?

27.     SPECIMEN # – Number assigned to the strength samples – cylinders or beams (example 1A, 1B, and 1C for three 4-inch x 8-inch cylinders specimen’s).

28.     DATE TESTED – Date the laboratory tests the specimens.

29.     AGE – Number of days from the date sampled to the date tested.

30.     STRENGTH PSI

31.     TRACKING # - Internal laboratory number.

32.     TYPE OF FRACTURE – Description of how the sample broke.

Check List for Inspection

Concrete Plants – Either Readi Mix or Plant on Site

Producer/suppliers of concrete are responsible for delivery of concrete and quality control.  Items below are their responsibility but you or your District Concrete Monitor should randomly ensure these items comply.  When concrete delivery is not good, these items become more critical. 

When making these checks, ensure the supplier is with you, and obtain documentation from the supplier as to what corrections they will be making to conform to requirements.

1.        Check foundations of stockpiles for proper preparation and adequate drainage.

2.        Observe stockpiling of aggregate to ensure that handling does not cause segregation, contamination, or intermingling.

3.        Observe charging of plant bins to ensure that materials are not being intermingled.

4.        Check bins for adequate partitions to prevent intermingling of aggregate.

5.        Check scales with test weights throughout range of use and determine percent of error.  If error is greater than ± 0.5 percent, scales must be adjusted and rechecked.  Record checks made and issues.  Do not accept concrete until corrected.

6.        Determine how the supplier will determine moisture content of their aggregates.  Calibrated probes are acceptable as are moisture tests.  Agree on the frequency of moisture and probe calibration.  Work with your district concrete monitor on these issues.  Depending on the job size, randomly verify moistures of aggregates.

7.        Check scales for seal by the Sealer of Weights and Measures or of a scale servicing company.  Record.  If not sealed, do not accept concrete.

8.        Check scales for "zeroing."  Have adjustments made when needed.

9.        Check water meter, both plant and truck, for accuracy. Record information.  Do not accept concrete from equipment not meeting 499.

10.     Randomly ensure that truck wash water is removed from the truck.

11.     Check admixture dispensers for accuracy. 

12.     Check mixers to ensure that hardened concrete is not built up around blades.

13.     Inspect hauling units for cleanliness, condition of blades, and operation of counters.

14.     Check to ensure that all materials have been sampled, tested, and approved or certified prior to start of concrete production. 

15.     Ensure quantities obtained from the Job Mix Formula (JMF) are adjusted for changes in specific gravity, moisture, and absorption.  Discuss with the supplier how they are doing this before delivery of concrete.

16.     Ensure aggregate quantity adjustments are within the acceptable range of 499 based on the JMF quantities.

17.     Observe batching operations at start of production and periodically when required.

18.     During mixing or delivery from the truck, do not accept balling of materials.  Do not accept attempts to remove balls by hand.  Reject the mixing operations or trucks.

19.     If water is added at project site, ensure 30 additional mixing revolutions are required

20.     Ensure you receive both batch tickets.  If the first ticket of the day is not provided, immediately notify the supplier.

21.     Do not accept handwritten batch tickets.

22.     Assure retarder is added when temperatures require and assure the dosage meets the manufacturer’s requirements.

23.     Notify supplier to make adjustments as needed to maintain air, slump, and yield within tolerance.  When slump adjustments are done with superplastizer on the jobsite, ensure a Type F or G is used and dosages are within manufacturer’s recommendations.

24.     Ensure W/C ratios are not exceeded at any time.  Immediately require corrections and report the quantity of material with high W/C ratios and non-specification material.

25.     Ensure trucks discharge all concrete within the required time from batching to discharge. (499)

26.     When adjustments are made in the mix design, check to ensure that proper batch weights are shown on tickets.

27.     Periodically check transit and central mixers to ensure compliance with manufacturer's recommended mixing speeds.

28.     Complete SiteManager TE-45 Report or test screens and submit to the District laboratory.

Conversion Factors:

MULTIPLY

BY

TO GET

Area

1 square foot

1 square inch

0.0929034*

645.16*

square meter    (m²)

square millimeter  (mm²)

Length

1 inch

1 foot

1 mile

25.4*

0.3048*

1.609344

millimeter(mm)

meter (m)

kilometer (km)

Mass

1 pound

0.453592 4

kilogram (kg)

Mass

 per volume

1 pound/cubic foot

1 pound/cubic yard

1 pound/gallon

16.018846

0.5932764

0.1198264

kilogram/cubicmeter

 (kg/m³)

kilogram/cubic meter

(kg/m³)

kilogram/liter  (kg/L)

Pressure

 (stress)

1 pound/square inch

1 pound/square foot

0.0068944

47.88026

megapascals (Mpa)

pascal (Pa)

Temp

Fahrenheit (oF)

(oF-32)/1.8)

Celsius (oC)

Volume

1 fluid ounce

1 cubic yard

1 cubic foot

1 cubic foot

1 gallon

29.57353

0.7645549

0.02831685

28.31685

3.785412

milliliter (mL)

cubic meter (m³)

cubic meter (m³)

liter (L)

liter (L)

Volume

per mass

1 fluid ounce / cubic yard

1 fluid ounce / 100 pounds

1 gallon / cubic yard

38.68071

65.19847

4.951132

milliliter/cubic meter

(mL/m³)

milliliter/100 kilogram

(mL/100 kg)

liter/cubic meter

(L/m³)

*exact conversion

Documentation Requirements - 499 Concrete

1.        Fill out the SiteManager TE-45 and report results in SiteManager.

a.        Ensure that specified w/cm ratio is not exceeded.

b.        Record temperature of mix.

c.        Record mix design adjustments on form TE-45.

d.        Make sure that correct aggregates being used match the JMF.

e.        When reporting Contractor reported test results, only complete test screen

                                                               i.      PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS.

f.         When reporting tests, ODOT has performed complete test screens.

                                                               i.      PCC INSPECTOR DAILY REPORT TE45 PART 1 – BATCH WT.

                                                              ii.      PCC INSPECTOR DAILY REPORT TE45 PART 2 – TESTS.

2.        If water is added at project site, document and check the w/cm is not exceeded.

3.        Document that pavement aggregates meet 703.13.

4.        Document random aggregate moisture checks.

5.        Ensure that batch tickets are provided as specified in 499.07.

a.        Randomly check batching quantities on ticket against JMF.

                                                               i.      When performing verification testing, check the time loaded and the time discharged are within requirements.

AASHTO M 157

The following is a direct reprint from AASHTO M 157 Standard Specification for Ready-Mixed Concrete.  The reprint is only the paragraphs referenced in 499.05 B. of the specifications (Sections 10, 11.2, 11.5, 11.6).

AASHTO M 157 Sections 10, 11.2, 11.5, 11.6

10.          Mixers and Agitators

10.1         Mixers may be stationary mixers or truck mixers. Agitators may be truck mixers or truck agitators.

10.1.1      Stationary mixers shall be equipped with a metal plate or plates on which are plainly marked the mixing speed of the drum or paddles, and the maximum capacity in terms of the volume of mixed concrete. When used for the complete mixing of concrete, stationary mixers shall be equipped with an acceptable timing device that will not permit that batch to be discharged until the specified mixing time has elapsed.

10.1.2      Each truck mixer or agitator shall have attached, thereto in a prominent place, a metal plate or plates on which are plainly marked the gross volume of the drum, the capacity of the drum of container in terms of the volume of mixed concrete, and the minimum and maximum mixing speeds of rotation of the drum, blades, or paddles. When the concrete is truck-mixed, as described in 11.1.3, or shrink mixed as described in 11.1.2, the volume of mixed concrete shall not exceed 63 percent of the total volume of the drum or container. When the concrete is central mixed as described in 11.1.1, the volume of concrete in the truck mixer or agitator shall not exceed 80 percent of the total volume of the drum or container. Truck mixers and agitators shall be equipped with means by which the number of revolutions of the drum blades, or paddles may be readily verified.

10.2         All stationary and truck mixers shall be capable of combining the ingredients of the concrete within the specified time or number of revolutions specified in Section 10.5, into a thoroughly mixed and uniform mass and of discharging the concrete so that no less than 5 of the 6 requirements shown in Table 5 shall have been met.

Table 5 – Requirements for Uniformity of Concrete

Test Requirement Expressed as Maximum Permissible Difference in Results of Tests of Samples Taken from Two Locations in the Concrete Batch

Weight per cubic foot (weight per cubic meter) calculated to an air-free basis, lb/ft3 (kg/m³).

16 (1.0)

Air content, volume percent of concrete.

1.0

Slump:

     If average slump is 102 mm (4 in.) or less, mm (in.).

25 (1.0)

     If average slump is 102 mm to 152 mm (4 to 6 in.), mm (in).

38 (1.5)

Coarse aggregate content, portion by weight of each sample retained on No. 4  (475-mm) sieve, percent.

6.0

Unit weight of air-free mortar a based on average for all comparative samples tested, percent.

1.6

Average compressive strength at 7 days for each sample,b based on average  strength of all comparative test specimens, percent.

7.5 c

a - "Test for Variability of Constituents in Concrete." Designation 26, Bureau of Reclamation Concrete Manual, 7th Edition. Available from Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402.

 b - Not less than 3 cylinders will be molded and tested from each of the samples.

 c - Tentative approval of the mixer may be granted pending results of the 7-day compressive strength tests.

Note 5 - The sequence or method of charging the mixer will have an important effect on the uniformity of the concrete.

10.3         The agitator shall be capable of maintaining the mixed concrete in a thoroughly mixed and uniform mass and discharging the concrete with a satisfactory degree of uniformity as defined by Appendix A.

10.4         Slump tests of individual samples taken after discharge of approximately 15 percent and 85 percent of the load may be made for a quick check of the probable degree of uniformity (Note 6). These two samples shall be obtained within an elapsed time of no more than 15 minutes. If these slumps differ more than that specified in Annex A1, the mixer or agitator shall not be used unless the condition is corrected, except as provided in 10.5.

Note 6 - No samples should be taken before 10 percent or after 90 percent of the batch has been discharged. Due to the difficulty of determining the actual quantity of concrete discharged, the intent is to provide samples that are representative of widely separated portions, but not the beginning and end of the load.

10.5         Use of the equipment may be permitted when operation with a longer mixing time, a smaller load, or a more efficient charging sequence will permit the requirements of Appendix A to be met.

10.6         Mixers and agitators shall be examined or weighed routinely as frequently as necessary to detect changes in condition due to accumulations of hardened concrete or mortar and examined to detect wear of blades. When such changes are extensive enough to affect the mixer performance, the proof-tests described in Appendix A shall be performed to show whether the correction of deficiencies is required.

11.          Mixing and Delivery

11.2         Mixers and agitators shall be operated within the limits of capacity and speed of rotation designated by the manufacturer of the equipment.

11.5         Truck-Mixed Concrete- Concrete that is completely mixed in a truck mixer, 70 to 100 revolutions at the mixing speed designated by the manufacturer to produce the uniformity of concrete indicated in Appendix A. Concrete uniformity tests may be made in accordance with 11.5.1. and if requirements for uniformity of concrete indicated in Appendix A  are not met with 100 revolutions of mixing, after all ingredients, including water, are in the drum, that mixer shall not be used until the condition is corrected, except as provided in Section 10.5. When satisfactory performance is found in one truck mixer, the performance of mixers of substantially the same design and condition of blades may be regarded as satisfactory. Additional revolutions of the mixer beyond the number found to produce the required uniformity of concrete shall be a designated agitating speed.

11.5.1      Sampling for Uniformity of Concrete Produced in Truck Mixers- The concrete shall be discharged at the normal operating rate for the mixer being tested, with care being exercised not to obstruct or retard the discharge of approximately 0.1 m³ (2 ft³ approximately) shall be taken after discharge of approximately 15 percent and 85 percent of the load (Note 6). These samples shall be obtained within an elapsed time of not more than 15 min. The samples shall be secured and shall be kept separate to represent specific points in the batch rather than combined to form a composite sample. Between samples, where necessary to maintain slump, the mixer may be turned in mixing direction at agitating speed. During sampling, the receptacle shall receive the full discharge of the chute. Sufficient personnel must be available to perform the required tests promptly. Segregation during sampling and handling must be avoided. Each sample shall be remixed the minimum amount to ensure uniformity before specimens are molded for a particular test.

11.6         When a truck mixer or truck agitator is used for transporting concrete that has been completely mixed in a stationary mixer, any turning during transportation shall be at the speed designated by the manufacturer of the equipment as agitating speed.

AASHTO M 157 Appendix A

(Mandatory Information)

A1.          CONCRETE UNIFORMITY REQUIREMENTS

A1.1        The variation within a batch, as provided in Table 5, shall be determined for each property listed as the difference between the highest value and the lowest value obtained from the different portions of the same batch. For this specification, the comparison will be between two samples, representing the first and the last portions of the batch being tested. Test results conforming to the limits of five of the six tests listed in Table 5 shall indicate uniform concrete within the limits of this specification.

A1.2        Coarse Aggregate Content, using the washout test, shall be computed from the following relations:

P = (c/b) x 100

Where:

P =  Weight % of coarse aggregate in concrete.

c =   Saturated surface-dry-weight in kg (lb) of aggregate retained on the No. 4 (4.75-mm) sieve, resulting from washing all material finer than this sieve from the fresh concrete.

b =   Weight of sample of fresh concrete in unit weight container, kg (lb).

A1.3        Unit Weight of Air Free Mortar shall be calculated as follows:

A1.3.1.    Inch-pound units:

A1.3.2.    Metric units:

 Where:

M =         Unit weight of air-free mortar, kg/m³ (lb/ft³).

b =           Weight of concrete sample in unit weight container, kg (lb).

c =           Saturated surface-dry-weight of aggregate retained on No. 4 (4.75-mm) sieve, lb (kg).

V =          Volume of unit weight container, ft³ (m³).

A =          Air content of concrete, percent, measured in accordance with Section 18.1.4 on the sample being tested.

G =          Specific gravity of coarse aggregate (SSD).

500 Structures

501 Structures - General

Engineering

When the Contractor performs survey work, the Engineer shall verify the Contractor’s accuracy by observation of the work and review of notes.  A state survey crew should be available to check any part where this accuracy is not obtained.  The Contractor’s surveyor should cooperate with the Engineer and provide the notes on critical work, such as bridge seat elevations, profiles of beams or girders, and grade for finishing the deck for review and concurrence.  Information that indicates the elevation of bridge seats and deck grades have been properly set and must be recorded in the project file.

Relations between the Engineer and surveyor should be in the spirit of cooperation toward achieving the common goal of bridges constructed of specified quality, in plan location, and on proper grade that will benefit both the state and the Contractor.

Working Drawings and Calculations (501.05)

When railroad involvement is required, as specified in 501.05.A, it is the Contractor’s responsibility to submit working drawings to the involved railroads for acceptance at least 50 days before construction begins.  The Contractor shall supply the Engineer with documentation proving railroad acceptance.  Department acceptance is not required. The following working drawings should be submitted to the Engineer at least 7 days before construction begins.  These working drawings shall be prepared by an Ohio Registered Professional Engineer (PE) and checked by a second PE.  No Department acceptance is required. Lack of departmental acceptance does not supersede the Engineer’s authority per C&MS 105.04.

1.        Sheeting and excavation bracing which impacts active traffic or with an exposed height over 8 feet or when required by contract, except when a complete design is shown in the plans.

2.        Demolition of structures over or adjacent to active traffic.

3.        Falsework for cast-in-place concrete slab bridges.

4.        Erection of steel or precast concrete structural members.

5.        Jacking and support of existing structures.

6.        Construction loads applied to a structure during construction in excess of 75 percent of legal load.

7.        Structures for maintaining traffic.

Although no Department acceptance is required, these working drawings should be utilized in the field as the standard to judge whether the Contractor is performing the work correctly. 

Stop all operations that do not follow the prepared working drawings. The Contractor must submit to the Engineer any revised working drawings, which are prepared by an Ohio Registered Professional Engineer, 24 hours before construction on the deviated work begins.

If the Contractor requests to weld to a main structural member that is not shown on the Contract drawings, he must submit a plan to the Office of Structural Engineering for acceptance at least 20 days before construction begins.

If a Contractor has to perform corrective work on structures items, the Contractor must submit three copies of a corrective work plan (CWP) to the Engineer, including supporting calculations prepared by an Ohio Registered Professional Engineer. The Engineer will submit the CWP to the Office of Structural Engineering for review and acceptance prior to performing corrective work.

When traffic is maintained while an overhead structure is being removed, platforms, nets, or other devices must be provided to safeguard the traveling public from falling objects that might fall directly onto the roadway below, be deflected toward the traffic, or bounce into traveled lanes.  Removal of superstructure concrete and structural steel shall, in no case, take place directly over traffic due to the possibility of large pieces falling through the protective devices.

Documentation Requirements - 501 Structures

This section outlines the Contractor’s requirements for fabrication, shop drawings, material certification, and erection procedures.

1.        Use Erection Checklist Form CA-S-20.

502 Structures for Maintaining Traffic

Description (502.01)

This item consists of the construction, maintenance, and subsequent removal of a temporary bridge or culvert for maintaining traffic.

Design and Construction (502.02)

The waterway opening generally should be not less than 75 percent of the effective waterway of the proposed structure based on the 5-year water level.  The deck of a bridge must have at least a 23-foot (7.0 m) clear roadway, and if pedestrian facilities existed, at least a 4-foot (1.2 m) wide sidewalk must be provided.

The proposed working drawing should be reviewed in the District for accuracy of existing features not shown on the project plans.  If the proposed waterway is less than 75 percent, comments regarding local knowledge of stream fluctuations will be helpful.  In lieu of a bridge, a pipe culvert or multiple pipe culverts with required waterway, may meet the requirements for a bridge and will be considered when submitted.

Submit construction working drawings in accordance with 501.05.

All stress-carrying materials to be used in any temporary structure must be carefully examined since used materials generally are employed and may not possess the physical properties considered in the design.  Timber elements must be examined for specified size and soundness.  Steel members must be examined for holes and alterations that would reduce their section modules.  Welded splices in members are not cause for rejection providing the welds have been made properly and are free from defects.  Existing welded butt splices must be subject to radiographic inspection.  Approved welders using approved welding consumables should perform welding. Hardware and miscellaneous materials must be as specified on the submitted plan.

Piles must be driven in accordance with 507.  The bearing capacity of each pile must be as specified on the submitted plan, but in no case, less than 12 tons (107 kn).  If piles are not driven to bedrock, the Contractor is responsible for performing the dynamic load necessary to determine the required blow count.

Construction of the temporary structure must be according to details and notes shown on the submitted working drawing.  Proposed substitution of elements of equal or greater strength may be made.  All other proposed substitutions or changes in design must be submitted in an amended working drawing meeting the requirements of 501.05.

When the plans permit the use of an existing superstructure as part of a temporary run-around, the bridge shall be relocated so there will be no reduction in load carrying capacity.  The working drawings for temporary substructure units must be submitted in accordance with 501.05.

Maintenance (502.03)

The Contractor is required to maintain the temporary structure in good condition with respect to safety, ride quality, and waterway opening for the duration of the run-around.  Periodic inspection of the structure must be made and any questionable members or connections that are damaged or over-stressed must be corrected immediately.

Documentation Requirements - 502 Structures for Maintaining Traffic

1.        Document structure and its conformance to the plans.

2.        Document date installation starts and when the structure is removed.

503 Excavation for Structures

Cofferdams and Excavation Bracing (503.03)

The Contractor may elect to use whatever materials or methods he considers necessary to accomplish this item unless specific details are required by the plans.  Many times when sheeting is installed into streambeds, the streambeds consist of sand or gravel.  Sand and gravel are pervious materials and will allow water to flow through them.  If this condition exists, water can flow under the sheets and come up through the bottom of the cofferdam.  This can loosen the soil in the bottom of the cofferdam and cause it to be very soft and unstable.  It can also result in water coming up through any freshly-placed concrete.  If this situation exists, the Contractor should take measures to prevent the flow of water up through the bottom of the cofferdam.  These measures can consist of driving the sheet piling deep enough to cut off the flow of water or placing a concrete seal in the bottom of the cofferdam prior to pumping out the water.  If additional measures are required, they are considered to be part of the cofferdams and excavation bracing item and no additional compensation should be allowed for these items.

In order to qualify as cofferdams and excavation bracing for a particular substructure unit, the Contractor must perform work to protect and maintain the excavation at that particular substructure unit. This work can include pumping out water, installing cribs or sheeting, sloping the sides of the excavation, or building an earthen cofferdam.

Unclassified Excavation

This item may include bedrock and may require the removal of all materials necessary for the construction of structures according to plan.  It also includes subsequent backfill and disposal of excavated material.

Protection

Sides of excavation should be protected from caving.  If side failure occurs, the disturbed soil should be removed and replaced with properly compacted soil.  The sides must not be laid back to the extent where the slope will endanger the stability of adjacent foundations.  The stability of the slopes needs to be determined by a competent person on the Contractor’s staff.  

Undercut for Spread Footings

When footings are not on piling, any material undercut, disturbed below plan, or authorized elevation must be replaced with concrete at the Contractor’s expense.  If the excavation is allowed to remain exposed for a considerable period of time, and the material becomes unsuitable, it must be removed and replaced with concrete at the Contractor’s expense.  The additional concrete may be placed with the footing concrete; however, the footing reinforcing steel must be located at the elevation indicated on the plans. 

Many Contractors will place gravel in the bottom of the excavation to assist in dewatering and to provide a better work surface for the workers.  This is unacceptable as any over excavation of spread footing subgrades must be replaced with concrete, not gravel.

Undercut for Pile Foundations

When footings are supported on piling, any material undercut or disturbed must be replaced with properly compacted material.  If the bottom of the excavation becomes muddy, the Contractor may remove the muddy soil and replace it with suitable granular material.

Drainage

When the cofferdam and excavation bracing item is not provided, drainage outside the forms and pumping necessary to keep the surface suitable for placement of concrete are included in the excavation item.

Rock Excavation

This item includes removal and disposal of material that, in the opinion of the Engineer, is rock or durable shale.  Shale that is removed by the same methods and comparative effort as soil should be classified as nondurable shale.

Methods

Rock or durable shale may be removed by whatever methods the Contractor chooses.  These usually are blasting, jack hammering, or ripping.  Note the option to excavate by blasting may be excluded due to the close proximity of existing facilities.  It is desirable to have rock excavation below the tops of footings and as near to the sides of the footings as practical.

Qualifications for Payment

To qualify for payment as rock excavation, the Engineer must determine that the excavated material is indeed rock or durable shale.  In addition, all of the rock excavation below the footing top must be filled with concrete.  Rock excavation performed above the top of footing may be to any width; however, payment above, as well as below the top of footing, is to the plan dimensions of the footing only.

Elevation Changes

In the event bedrock is encountered over 1 foot (0.3 m) higher than indicated by the borings, or bedrock is not encountered at plan elevation, report the findings to the District Construction Administrator for consideration of a change in elevation of the footing.  A plan note will usually be provided indicating when raising the footing can begin.  When bedrock is not encountered at footing elevation, an investigation of the soil should be made as deep as practical.  Hand augers or probes are recommended for initial investigation.

Generally, when bedrock is found less than 1 foot (0.3 m) lower than plan elevation, the additional height of pier or abutment can be provided by additional footing concrete; however, reinforcement should be placed at plan elevation.

When bedrock is found 1 foot (0.3 m) or more below plan elevation, consideration should be given to lengthening the pier or abutment above the footing.

Relative costs should be investigated in either case, and if the cost difference is significant, should be reported to the District Construction Administrator for review.

Approval of Foundations (503.06)

When the foundations for a bridge are spread footings, they are designed to be supported on soil or bedrock as indicated by the soil borings.  The Engineer must examine the soil or bedrock encountered at plan elevation for agreement with soil boring data and to ensure that it will provide the intended bearing capacity.  This bearing capacity will be listed in tons per square foot (tonnes per sq. meter) in the plan notes.  Consult the District Geotechnical Engineer or Office of Geotechnical Engineering with any questions.

Questionable Support

The District Geotechnical Engineer or Office of Geotechnical Engineering should be consulted whenever there is doubt that the material encountered at plan elevation will provide the necessary bearing capacity.  Whenever the material encountered is different, and of lesser quality than indicated by the borings, an investigation similar to that described in the section titled, Elevation Changes, should be made and the findings reported to the District Geotechnical Engineer for review.

Cold Weather Excavation

Footings placed on pile foundations that were exposed to temperatures below freezing sometimes settle during the setting of the concrete and result in unsatisfactory footings.  Therefore, it is imperative that soil in such cases be free from frost, and if disturbed by freezing, compacted to proper density.

Protection

When excavation for footings is performed, and freezing temperatures are expected during the time it is exposed, insulation such as an adequate thickness of straw is recommended for protection from frost.

Examination

When the excavated area has become frozen, and the area is heated in an enclosure, the effect of the supplied heat on the frozen soil is slight, and a thorough examination for complete removal of frost is required.  Satisfactory temperatures found in spot checks of soil where frost may have penetrated are an indication of frost removal.

When frozen soil is thawed out, it requires re-compaction since frost heaving has lessened the density.  If reinforcing steel has been placed in a footing area at the time the soil was frozen, it will be necessary for the Contractor to remove the reinforcing steel prior to re-compacting the soil.

Backfill (503.08)

The backfill material behind the abutments and beneath the approach slabs shall conform to Item 203 Granular Material Type B. The use of this material should facilitate compaction and help alleviate the settlement of the approach slab.

Method of Measurement (503.09)

Measurement of Excavation Prior to Altering the Original Ground Line

When the plans do not require the original ground line to be altered by removal of the embankment, and when structural excavation is performed prior to building an embankment, elevations or measurements that establish the elevation of the original ground must be made.  Measurements made and recorded from the Contractor’s footing grade stakes can be used to establish the elevation of the original ground.

Measurement of Excavation Made After Altering the Original Ground Line

When the original ground is altered by removal or construction of an embankment prior to excavation, use the plan line of the excavation or embankment items for top boundary of excavation.

Verification of Footing Elevation

The bottom elevation of the footing is to be as shown in the plans.  This elevation is to be verified by subtracting the total verified height of the substructure unit below the beam seat from the beam seat elevation.

Documentation Requirements - 503 Excavation for Structures

1.        Verify existing ground elevations.

2.        Verify that Contractor excavated to plan dimensions.

3.        Make sure that the volume of the existing structure is deducted from the pay quantity for unclassified excavation.

4.        Compaction of backfill documented on CA-EW-5 Form.

Dispose of excavated material not needed or unsuitable per 105.16 and 105.17.  Note: In recent years this item has been bid as a lump sum.  Numbers one and two still apply.

504 Sheet Piling Left in Place

Materials (504.02)

Material for sheet piling must conform to 711.03, which refers to ASTM A328.  Sheet piling that conforms to ASTM A328 is acceptable.  Used sheet piling may be used if it meets the project requirements and is approved by the Engineer.

The Contract Documents will specify the minimum section modulus in cubic inches per foot of wall length.  Any hot rolled or cold rolled sheet piling which meets or exceeds this requirement is acceptable.

Driving (504.03)

Steel sheet piling is not driven based on any driving criteria, but is driven based on a specified tip elevation.

Steel sheet piling will normally be driven with a vibratory hammer suspended by a crane or an excavator mounted sheet driver.  In difficult driving conditions, diesel impact hammers can be used, but it is more likely that the top of the sheets will crush.

Sheet piling is always interlocked with the adjacent sheets.  The manufacturer will fabricate a special shape if sharp corners or junctions are required in the wall.

Documentation Requirements - 504 Sheet Piling Left in Place

1.        Document sheet piling section modulus.

2.        Measure area for payment.

505 Pile Driving Equipment Mobilization

Basis of Payment (505.02)

Payment is not to be made when the equipment arrives on site, but once the first service pile is installed and accepted. 

Documentation Requirements - 505 Pile Driving Equipment Mobilization

1.        Document equipment arrival and add to diary for payment.

506 Static Load Test

Description (506.01)

Static load tests are performed on piles to determine the accuracy of dynamic load test results and to determine if the capacity of the pile being tested has increased or decreased after it has set in the ground for some period of time.  The intent of performing the static load test is to potentially reduce the driven length of pile by fine-tuning the pile capacity determination.  There must be a substantial amount of piling at a structure to justify the expense of a static load test.  Generally, 10,000 feet of piling (all of the same size and ultimate bearing value) is the amount required before specifying a static load test.

Static load tests are not performed very often and can be complex and must be performed properly for the results to be useful.  Always contact the Office of Construction Administration or the Office of Geotechnical Engineering for assistance before performing a static load test.

With the 2013 C&MS, the Department adopted the ASTM Quick Load Test method for static load testing. The duration of the static load test using this method is generally 8 to 10 hours.  Using the previous method, the test could take longer than 24 hours. The other significant change with the 2013 C&MS is that the Contractor is responsible for taking the readings.  Previously, the Department was responsible for taking readings during the test.

Determination of Need

The Office of Construction Administration or the Office of Geotechnical Engineering must be consulted before non-performing the static load test.  Consult either of these two offices to determine if a subsequent static load test should be performed.

Static load tests are not performed on piles driven to refusal on bedrock.

General (506.02)

Pile Wall Thickness

Most static load tests are performed on cast-in-place piles (also called pipe piles or tube piles).  The static load test will place a load on the test pile that is twice the Ultimate Bearing Value (UBV); therefore, the test pile may need a thicker wall than that required by 507.06 or the Contractor will have to fill the pile with concrete and allow the concrete to cure for 5 days.

For test piles, if the wall thickness is less than the required wall thickness given by the equation below, then the Contractor must fill the pile with concrete and allow the concrete to cure for 5 days before performing the static load test.

Where:

t = Shell wall thickness (inches)

R = Ultimate Bearing Value, UBV (pounds)

D = Diameter of pile (inches)

If the test pile wall thickness is equal to or greater than the wall thickness given by the above equation, the Contractor can perform the static load test 72 hours (3 days) after he has finished driving the test piles and anchor piles.  Generally, piles with a diameter of 16 inches or greater will meet the minimum wall thickness requirement for the test pile.  Depending on the UBV, 12-inch and 14-inch piles may not be available with the minimum wall thickness for test piles.  These piles will have to be filled with concrete before the static load test.

Driving Test Piles

The test pile can be, and usually is, a production pile.  The test pile must be vertical. Sometimes people are concerned about “failing” a production pile. This should not be a concern.  In fact, it is desirable to “fail” the test pile as when this happens, we determine the true capacity of the pile and achieve the most value from the test.  In the case where a test pile, which is also a production pile, “fails” during the static load test at a capacity lower than required, the solution is usually as simple as splicing on more pile length and driving the pile deeper.

The standard plan note for a static load test requires the Contractor to drive four piles, not including the anchor piles.  The first two driven piles are test piles.  Each one is driven to the required UBV as determined by the dynamic load test.  This means both of these piles are dynamic load tested (that is one dynamic load test item).  Do not overdrive these first two piles.  Perform the static load test on one of these two piles.  If the first pile is not suitable to use for the static load test, the second pile is driven as a backup.  The dynamic load test on the second pile gives additional data that can be used to interpret the static load test results.  The third and fourth piles are driven to reduced blow counts 75 and 85 percent of the driving criteria. For example, if the driving criteria from the dynamic load test is 40 blows per foot (bpf), then the third pile is driven to 30 bpf (0.75 × 40), and the fourth pile is driven to 34 bpf (0.85 × 40).  It is important that the third and fourth piles be shorter than the test pile, so the person interpreting the test data can make an accurate evaluation.  The exact method of determining shorter length is not critical.  They can also be driven to 75 and 85 percent of the length, or some other lengths shorter than the test pile.  The third and fourth piles are also dynamic load tested (one more dynamic load test item).

In some soil, piles will gain capacity with time. This is called pile set-up or sometimes, pile freeze.  The reduced capacity piles are driven to see if the pile will gain enough capacity with time to meet the Ultimate Bearing Value requirement.  If there is some increase in capacity, but not enough to meet the UBV, then we can still estimate the appropriate driving criteria if we know the amount of pile set-up.  To do this, we need to know the capacity at the end of the initial pile driving, which we can determine from the dynamic load test.  This is why we dynamic load test the reduced capacity piles.

Anchor Piles

Production piles can be used as anchor piles.  Vertical piles are preferred for the anchor piles, but the Contractor may use battered piles for the anchor piles as long as the battered piles are symmetric around the test pile.  The Contractor determines the number of piles to use as anchor piles and the required length of penetration.  Anchor piles must be at least 8 feet (2.5 m) from the test pile, measured from center-to-center.  If the anchor piles are also production piles, they may need to be re-driven to the required driving criteria after the static load test, depending on the test results.

Generally, the test pile should be driven before the anchor piles, but this is not required.  If the anchor piles were driven first and there was a problem with the first test pile so that the backup test pile had to be tested, then the Contractor would have to drive additional anchor piles around the backup test pile.

No other production piles are to be driven until after the results of the static load test have been interpreted. However, the Engineer can allow the Contractor to proceed with pile driving at his own risk, with the understanding that the Department will not pay for piling driven deeper than required based on an evaluation of the static load test results.

Application of Load (506.03)

The Contractor must wait at least 72 hours (3 days) after driving the test pile and anchor piles before applying the test load.  If the Contractor has filled the test pile with concrete because it does not meet the minimum wall thickness requirement, then the Contractor must wait 5 days before applying the test load.  The plan notes may require a longer waiting period.

The test pile should be cut off as near to the ground as practical and the jack placed along the axis of the pile with full bearing on the required load cell and bearing plate.

Instruments

The Contractor must furnish a set of gauges or devices capable of accurately determining settlement of the pile to 0.001 inch (0.025 mm) and a calibrated load cell for determining the load applied.  Dial gauges must have graduations every 0.01 inch (0.25 mm) or less.

The gauges used to measure the settlement of the pile should be placed opposite each other and should be placed at the sides of the pile.  They should be supported from posts or fixed objects.  The post or fixed objects are to be independent of the test load set-up and at least 4 feet (1.25 m) away from the test pile.  However, the gauges should be placed as close to the test pile as possible.  Dial gauges are furnished and should have sufficient travel to measure up to 2 inches (50 mm).  A backup system is required in case of problems with the gauges.  The backup system usually consists of a ruler applied to the test pile, with a mirror and string line for measuring settlement.

The primary means of determining the applied load is a calibrated load cell.  The pressure gauge on the hydraulic jack can be used as a backup load measuring system.  The pressure gauge alone is not accurate enough for the static load test.  Also, if the jack should bind up, the hydraulic pressure would increase while the load transmitted to the pile would not necessarily increase.

Loading

The load is to be applied in increments consisting of a first increment of 1/10 the UBV of the pile (R).  The Contractor records the dial gauge readings for each gauge 1, 2, 4, 8, and 15 minutes after each load increment is applied.  Calculate the average pile settlement from the gauge readings.  Apply the next load increment after the 15 minute reading.

Maintain the test load during each load increment.  Due to settlement of the pile, the load and pressure in the jack may decrease with time.  The Contractor should run the hydraulic pump as necessary to maintain the load on the pile.

Continue to increase the test load until the load is twice the UBV or the pile reaches plunging failure.  Plunging failure is defined when continuous jacking is required to maintain the test load.

Unloading

After loading is complete or plunging failure is reached, unload the pile in five equal decrements in 15 minute intervals.  Record the settlement readings at 1 and 15 minutes after each load decrement. After the entire test load has been removed from the test pile, record the settlement after 1 and 15 minutes.

If it is necessary to remove and reapply the load, such as a problem with the jack or load cell, reapply the test load using the same procedure used to apply the initial loads.

Load Test Results

The test load Ultimate Bearing Value (Qf) is the maximum capacity of the test pile.  To determine Qf, it is necessary to plot the settlement of the top of the pile versus the load on the pile.  Draw a straight line through the zero point and the theoretical elastic settlement of the pile using the equation in the specification. This line represents the elastic compression of the pile (the distance that the pile compresses under the test load).  Draw another line parallel to the first, but offset by the distance given in Equation 506.1.  The second line is called the Davisson criterion line.

0.15 inch + 0.008 D                ( 3.8 mm + 0.008D )

Equation 506.1 – Settlement Offset

Where:

D = Diameter of pile (inches or millimeters)

The point where the load-settlement curve from the static load test intersects the Davisson criterion line is the test load Ultimate Bearing Value (Qf).  An example from an actual static load test is shown in Figure 506.A.

In some cases, the slope of the unloading portion of the curve can be used to determine the elastic compression of the pile.

If the load-settlement curve does not intersect the Davisson criterion line, then Qf is equal to the greatest test load applied (2R).

Figure 506.A – Load-Settlement Curve

Restrikes

The standard plan note for a static load test requires the Contractor to restrike the test pile and the two reduced capacity piles.  The note may require re-striking the backup test pile.  The restrikes are performed at least 7 days after the piles were driven.  Each restrike test consists of dynamically testing two piles and determining the capacity of the piles.  Pile set-up is the increase in capacity for a pile from the time it was initially driven to the time it was re-struck.  Ideally, the capacity from the restrike test on the test pile should be close to the results of the static load test.

Application of Results

Either the Office of Construction Administration or the Office of Geotechnical Engineering will review the pile driving logs, the static load test results, the dynamic load test results, and the restrike test results, and then recommend the driving criteria for the production piles.  Wait for the recommended driving criteria before letting the Contractor drive the rest of the production piles. However, the Engineer can allow the Contractor to proceed with pile driving at his own risk, with the understanding that the Department will not pay for piling driven deeper than required based on the recommended driving criteria after the evaluation of the static load test results.

The static load test results will apply to the same type and size of piling, driven with the same type of hammer, to approximately the same depth, with similar driving characteristics as the test pile.

The pile hammer used for driving the test pile shall be used for driving all piles represented by the static load test.  If the Contractor subsequently finds it necessary to use a different size and type of hammer, the Office of Geotechnical Engineering or the Office of Construction Administration will determine if an additional static load test is required; any such additional static load test shall be completed at no additional cost to the Department.

Documentation Requirements - 506 Static Load Test

Documentation for the static load test consists of the driving logs of the test piles and reduced capacity piles, the dynamic load test report, the restrike test report, and the load-settlement readings from the static load test.  Identify the piles using the pile numbering system on the plans if the piles tested are production piles.

507 Bearing Piles

Description (507.01)

A pile is a structural column of steel, concrete, timber, etc. that is installed in the ground to support a structure above it.  Piles are required when the soil near the surface is not strong enough to support the structure or when the soil may be scoured away.  Piles transfer the loads from the structure to deep layers of soil or rock that are capable of supporting the load.

The term, “bearing pile,” refers to a pile that is used to support a structure. A bearing pile is also called a service pile or a production pile.

The plans include a foundation layout which identifies each pile with a unique number and indicates the pile type, size, and direction of batter (if any).  Use the unique number to identify the pile in the construction documentation.

General (507.02)

There are many types of piles; however, the Department generally uses either cast-in-place reinforced concrete piles or steel H-piles that are driven into the soil using an impact hammer.  The cast-in-place piles are constructed by driving a hollow steel tube, capped at the bottom with a steel plate, into the ground, and then filling the tube with concrete.

The plans give the estimated length for each pile.  However, the Contractor decides whether to drive a single pile segment for the entire estimated length or to drive shorter segments and splice them together as he drives the pile into the ground.

Materials (507.03)

The steel for H-piles must conform to 711.03 which refers to ASTM 572, Grade 50 (Fy=50 ksi). This is the industry standard for H-piles.  The steel pipe for cast-in-place piles must conform 711.07 which refers to  ASTM A 27 Grade 65-35 or Grade 70-36 or AASHTO M103 or ASTM A 148 Grade 90-60.

Driving of Piles (507.04)

Piles are typically driven to a specified capacity (Ultimate Bearing Value) or to refusal on bedrock.  The Ultimate Bearing Value, or UBV, is equivalent to the ultimate pile capacity (in Allowable Stress Design) and the nominal pile resistance (in LRFD).  The UBV is the required capacity of the pile. Sometimes the plans list the design bearing, the design load, or the factored load in addition to, or in place of, the UBV.  Do not mistake the design load for the capacity to which the piles are to be driven. 

Typically, H-piles are used when piles are driven to refusal on bedrock, and cast-in-place piles are used when piles are driven to a specified capacity.  However, H-piles are sometimes used when driving to a specified capacity.

In some cases, such as bridges over water, where scour may be a concern, the plans may indicate a minimum pile tip elevation in addition to the UBV.  If both a UBV and a minimum pile tip elevation are specified for the piles, both criteria must be met.  If the pile is driven to the required tip elevation before reaching the UBV, continue driving until the pile has the required capacity.  If the pile is driven to the UBV before reaching the minimum pile tip elevation, continue driving until the pile tip is at the required elevation.

If during the driving operation the pile begins to crush, the driving operation must immediately cease and the crushed section of the pile removed.  This is due to the fact that the crushed section will behave similar to a sponge and the energy from the pile hammer will no longer be properly transmitted to the tip of the pile.  This results in higher blow counts with minimal penetration of the pile into the ground.

Piles Driving Longer or Shorter than Estimated

In the event a pile reaches 150 percent or more of the estimated depth without achieving capacity or in the event of a pile reaching capacity in less than 80 percent of the estimated depth, about two more piles should be driven in scattered locations to verify this trend.  If these piles also exceed the above limits, contact the Office of Construction Administration or the Office of Geotechnical Engineering for advice.  You may also contact the District Geotechnical Engineer for advice.  Complete information regarding equipment, the driving logs, and any unusual driving experiences should be provided for review.  During this review, the Contractor may be permitted to continue his driving operation.  However, the Contractor should not be required to attempt to drive the piles to 80 percent of the estimated penetration.  He should also not cut the piling off until after the review.

Occasionally, when bearing is achieved before the pile has been driven 80 percent of the estimated penetration, project personnel require the Contractor to continue driving the pile to achieve a penetration of 80 percent of the estimated depth.  This is not recommended.  The value of 80 percent of the estimated penetration is only a guide to aid project personnel.  Overdriving the pile may result in damage to the pile or the pile hammer.  Do not require the Contractor to overdrive the pile to obtain the 80 percent length without first consulting with the Office of Construction Administration, the Office of Geotechnical Engineering, or the District Geotechnical Engineer.

Pile Driving Equipment

A driving cap that centers the pile under the hammer and uniformly transmits the blow must be used.

Driving leads guide the travel of the hammer and cap during driving and must be capable of keeping the hammer in line with the axis of the pile.  The leads should be equipped with a yoke at the base to center the pile and project beyond for anchorage.

Pile Hammers

Pile hammers are powered by compressed air, hydraulic oil pressure, or igniting diesel fuel.  These hammers are classified as either single-acting hammers or double-acting hammers. 

In addition to power driven hammers, a drop hammer may be used which has a ram weight of at least 3,000 pounds (1,360.8 kg) and a distance of fall not exceeding 7 feet (2.1 m).

Single-acting hammers are those that have their rams lifted by compressed air, hydraulic oil pressure, or igniting diesel fuel.  When the ram reaches the top of its stroke, it falls back to its original position by gravity.  Hammers that are powered by igniting diesel fuel and open on the top are considered open-end diesel hammers. These hammers allow the ram to become exposed during driving.

Double-acting hammers are those that not only have the ram lifted by compressed air, hydraulic oil pressure, or igniting diesel fuel, but in addition to gravity, compressed air or hydraulic oil pressure also impart a downward force on the ram.

Double-acting hammers that are diesel powered and are closed at the top are considered closed-end diesel hammers.  The space between the top of the ram and the top of the hammer casing is called the bounce chamber.  As the ram rises in the hammer, the volume of the bounce chamber decreases and increases the pressure of the air inside the bounce chamber. This increased air pressure imparts a downward force on the ram.

Hammer Size

The Contractor chooses the size of the hammer to use.  The hammer must be sized to the UBV of the piles.  Typically contractors in Ohio use an open ended diesel hammer with a rated energy in the range of 40 to 45 kip-ft., but may be different.  A hammer that is too small will not be able to drive the pile to the required UBV. A hammer that is too big may result in pile damage and may increase the risk of alignment difficulties.

The hammer must be large enough to drive the pile to the required UBV and successfully perform dynamic load testing. The use of a hammer that is too small will result in a hammer that will not be large enough to impact the piles with enough energy to successfully perform a dynamic load test.  Dynamic load testing cannot determine the total capacity of the pile being driven if the energy applied to the pile by the pile hammer is too low.  An example of this situation is the case where a cast-in-place pile has been driven to the top of a hard layer of sand and gravel that may be capable of supporting a load of over 300 tons.  If the maximum load that the pile hammer is able to place on the pile is only 120 tons, then the dynamic pile test will only register 120 tons and not 300 tons.  If the required UBV is 120 tons or less, then the hammer is large enough. However, if the required UBV is greater than 120 tons, then the pile hammer is not large enough to successfully perform a dynamic load test. Note: This is a simple example to demonstrate the concept. The actual relationship between hammer energy and pile capacity is much more complex. 

Performance of the Pile Hammer

The driving criteria or blow count that a pile must be driven to depends on the performance of the pile hammer.  If the performance of the hammer changes, then the appropriate driving criteria will also change.  Therefore, the performance of the hammer should be constantly observed.  The performance of the hammer should be compared with the results of the dynamic load testing to determine the required blow count. The Contractor is required to provide the Inspector with a means to monitor this operation.

Open-end diesel hammers are the most common type of pile hammer for highway contractors in Ohio.  A relatively easy way to monitor the performance of an open-end diesel hammer is to watch the stroke of the ram.  During the dynamic load testing, watch how far the rings on the ram come out of the hammer.  Then, during pile driving, make sure that the rings are coming out of the hammer about the same distance. The ram of an open-end diesel hammer falls by gravity; therefore, the stroke of an open-end diesel hammer can be estimated from the blow rate (blows per minute) using the following equation.

Where:

h = Stroke of pile hammer (feet)

bpm = Blows per minute

(From Design and Construction of Driven Pile Foundations, FHWA NHI-05-043, pages 21-28)

For convenience, the following table gives the results of the above equation for a typical range of values.  Additionally, the relationship between stroke and blows per minute for a particular pile hammer can be determined from the dynamic load test.

Blows per Minute

Stroke (ft)

Blows per Minute

Stroke (ft)

37

10.2

42

7.9

38

9.7

44

7.2

39

9.2

46

6.5

40

8.7

48

6.0

41

8.3

50

5.5

Trying to count the blows per minute while also keeping track of the blows per foot is difficult.  An easier way to determine the blows per minute while counting the blows per foot during pile driving is to measure the number of seconds required to drive one foot of piling.  Use the following equation to calculate the blows per minute.

Closed-end diesel hammers must be equipped with a gauge placed on the ground and connected to the bounce chamber by a hose.  The gauge shows the pressure developed for each stroke of the ram.  A graph, included with the gauge, can be used to convert the pressure to the energy developed by the hammer for each blow.  The hose connecting the gauge to the bounce chamber comes in different lengths that can affect the reading on the gauge.  Therefore, it is important to check that the graph corresponds with the length of hose used.

The Contractor can control the hammer’s operating energy by the use of a throttle or fuel setting.  The hammer must be operated during pile driving at the same setting used when the dynamic load test was performed.

Alignment in Leads

If the hammer is not properly aligned with the pile, the energy from the hammer will not be properly transmitted to the pile.  For the full effect of the hammer energy to be transmitted to penetration of the pile, the axis of the hammer must be in line with the axis of the pile.

Determination of Required Driving Criteria (507.05)

The driving criteria, or required blow count, is determined from the dynamic load test results.  See Section 523.  The first two piles are driven with the dynamic load test equipment attached.  The testing company should provide a preliminary recommendation for the driving criteria immediately after driving these two piles.  The driving criteria will be a minimum blows per foot for the pile driving.  For open-end diesel hammers, the driving criteria will also include a minimum hammer stroke.

Drive the rest of the piles to the recommended driving criteria.  Generally, it is not necessary to ensure the pile has a blow count greater than the required blow count for 3 or more consecutive feet.  For example, if the required blow count is 43 blows per foot, it is not necessary to drive the pile until the blow count is greater than 43 for 3 consecutive feet.  See the following table for examples.  The exceptions to this are if there is a minimum pile tip elevation, the depth of penetration is less than 80 percent of the estimate, or the pile has to be struck with 150 blows to inspect a splice.

Pile Driving Examples
Required Blow Count is 43 blows/ft

Penetration

Blows/Ft

Penetration

Blows/Ft

37-38

28

41-42

21

38-39

33

42-43

40

39-40

42

43-44

40

40-41

45

Should stop

44-45

43

41-42

43

driving here.

45-46

44

42-43

41

46-47

48

43-44

43

47-48

41

44-45

44

48-49

46

45-46

46

49-50

50

Cast-In-Place Reinforced Concrete Piles (507.06)

A cast-in-place reinforced concrete pile consists of a steel shell that is filled with concrete.  To minimize the possibility of the piles being damaged during the pile driving operation, it is important to maintain the minimum wall thickness specified in 507.06 of the Construction and Material Specifications.

Piles may be tapered or of uniform section.  The tapered piles are cylinder shells with vertical fluting or corrugations commonly referred to as monotube piles.  Monotube piles can be either tapered or of a uniform diameter. All other piles of uniform section are called pipe piles.  Tapered monotube point sections come equipped with a bullet-nosed tip.  Pipe piles usually have a plate welded on the point that must not extend more than 1/4 inch (6 mm) beyond the surface of the pile at any point.  The Engineer should ensure that the cast-in-place metal shell is of domestic origin and it conforms to ASTM 252A 27 Grade 65-35 or Grade 70-36 or AASHTO M103 or ASTM A 148 Grade 90-60.  A producing mill certification is often the simplest way to verify this.

The piles must be inspected and necessary measurements made.  Due to the possibility of lateral earth pressure causing adjacent piles to collapse prior to filling with concrete, this inspection and measurement should be made after all the adjacent piles are driven.  After the piles are driven, cover the tops until they are filled with concrete.  Before filing with concrete, remove water and debris.  Concrete required for filling the piles is Class QC 1 containing a superplasticizer admixture.  After the superplasticizer has been added, the slump should range from 6 to 8 inches (150 mm to 200 mm).  The concrete should be deposited in a steady, small stream to ensure complete filling and consolidation.  If there is reinforcing steel in piles, the concrete could become segregated from coming into contact with the reinforcing steel while it is dropping in place.  Use drop chutes to eliminate this problem.  No driving shall be performed within 15 feet (4.6 m) of filled piles until the concrete has cured at least 7 days.

Steel H-piles (507.07)

When H-piles are specified, the plans usually require that they be driven to refusal on bedrock.  The standard plan note gives a driving criterion of 20 blows per inch.  The note may allow the Contractor to perform a dynamic load test, at his own expense, to determine the driving criteria instead of using the 20 blows per inch criterion.

When the bedrock is hard and unweathered, refusal is obtained after the piles contact bedrock and have been struck at least 20 more times, with a penetration less than or equal to 1 inch (25 mm), to ensure that firm contact has been established.  Use care to avoid damaging the piles.

When the bedrock is soft or weathered, driving refusal is obtained at a resistance of 20 blows per 1 inch (25 mm).

Many times pile points or pile shoes are specified to be welded to the tip of the piles.  These points or shoes are made of cast steel as opposed to plates welded together and are used to protect the end of the pile from damage during the driving operation.

Mill test reports are required for steel H-piles and should be reviewed by the Engineer for conformance to 711.03 of the Construction and Material Specifications.  If pile points or shoes are specified, mill tests should be reviewed for conformance to 711.07

Timber Piles (507.08)

Although still included in the specifications, timber piles are no longer used by the Department.

Splices (507.09)

Splicing may be necessary to provide the required length to achieve bearing.  Numerous splices using small lengths in the same pile should be avoided, particularly in an area exposed to view.  Splices should be made at least 3 feet above the ground so that the weld may be observed while it is subjected to the impacts from the pile hammer.  If bearing is obtained prior to observing the weld during 3 feet of driving, the pile should still be driven a minimum of 150 blows after the splice is made in order to observe the weld.  When splicing structural shapes (H-piles), welding must be performed in accordance with 513.21 of the Construction and Material Specifications, which, among other things, requires the use of a prequalified welder.  See Figure 507.A - Joint Preparation for Groove-Welded H Pile for the method of making the required welded butt splice.  For H-piles, the plans may include a note that allows the use of a manufactured splicer in place of the full penetration butt weld.

Figure 507.A – Joint Preparation for Groove-Welded H-Pile

Note: If a different number of passes is required than shown in Figure 507.A, a similar sequence must be followed with the finishing pass on the reverse side. Back gouge root pass prior to making the finishing pass.

When pile points are specified in the plans, the Contractor must select a product from the Department’s approved list. The pile points must be welded to the pile according to AWS D1.5 or the manufacturer’s written welding procedure, which must be submitted to the Engineer before the welding is performed. Mill test reports must be submitted by the Contractor.

Defective Piles (507.10)

A pile is considered defective if damaged to the extent that the strength of its section is reduced over 20 percent.  This can occur as a collapse of the shell where less than 80 percent of the cross-sectional area remains open or where the shell is ruptured to the extent that the pile will have over 20 percent less strength.

A pile is also considered to be defective if the location of the pile, at the ground surface, differs from the specified location by more than 1 foot (0.3 m) for piles that are entirely underground or by more than 3 inches (75 mm) for piles that project above the ground, such as in a capped-pile pier.  No attempt should be made to draw these piles to their specified location.

Replacement Piles

If it is practical to withdraw a pile, the replacement can be driven in the specified location.  If the defective pile is not withdrawn, it must be filled completely with concrete.  If it is under a footing, it must be cut off slightly above the bottom of the footing where it will provide some support, but will not be paid for.  A replacement pile will need to be driven beside it.  The replacement should be located on the same line parallel to the side of the footing and battered slightly, if necessary, to avoid contacting the defective pile or adjacent piles.

When a replacement pile is driven alongside, rearrangement of reinforcing steel will be necessary.  If sufficient space is not available to avoid crowding of bars, it may be necessary to cut the bars at the pile and provide bars on either side lengthened for bond.  In lieu of this, the pile may be cut off below the reinforcement and the footing deepened approximately 1 foot (0.3 m) around the pile and below cutoff.

Only the replacement pile will be included for payment.  Any additional material or work required to make it a satisfactory pile will be at the Contractor’s expense.

Prebored Holes (507.11)

Abutment piling must be driven through embankments to bearing in the existing soil.  Sometimes pre-bored holes are provided in the plans to ensure this.  The prebored holes do not need to remain open before the pile is driven.

Method of Measurement (507.12)

The two main pay items associated with the pile driving operation are piles furnished and piles driven.

The quantity of piles accepted for payment as piles furnished will be based on the total order length specified in the plans and required by the Engineer. The order length is the pile length that the Designer estimates, as necessary, to achieve bearing.  The Contractor may elect to use piles longer or shorter than the order length as he determines necessary to meet his needs.  The Contractor is responsible for the cost of the splice if he elects to use piles shorter than the order length which then results in the need to splice the piles to achieve the required order length.

During the driving, the Engineer must monitor the length of piling necessary to obtain bearing.  If the order length given in the plans is not sufficient to achieve bearing, the Engineer should inform the Contractor of the necessary additional order length.  The Engineer should inform the Contractor as soon as possible to allow him to order the piles in a timely fashion and to avoid additional costs due to down time expenses. It will be necessary to negotiate with the Contractor and reimburse him for any additional splices necessary to provide additional length beyond the order length.

The pay quantity for piles driven shall be the sum of non-defective pile lengths measured along each pile’s axis from the bottom to the elevation of cutoff.  This quantity will be paid in addition to the quantity of piles furnished and may not necessarily correspond with the quantity of piles furnished.

Documentation Requirements - 507 Bearing Piles

1.        Use piling forms CA-S-3 and CA-S-8.

2.        State difference between piling delivered and piling driven. Excess piling furnished can be kept by project owner (ODOT or Local Public Agency).

3.        Measurements should be made to the nearest 0.1 feet (0.05 m).

4.        Make layout sheet showing pile location, pile number, test boring, structure number, north arrow, project number, whether pile is battered or straight, required bearing skew if applicable, offset of pile, and hammer that is being used.

5.        Height of drop hammer before release (if used).

The following data should be included in the project records.

1.        A driving log, CA-S-3 (Form BR-2-75) showing the blows per foot, stroke of the ram, or operating pressure for each foot of penetration.

2.        A record of measurements, CA-S-8, that establish the pay length of each pile. This may be determined by adding the penetration length to the amount protruding out of the ground after the pile has been cut off to the proper elevation or by the total pile length driven minus cutoff, whatever is sufficiently accurate and most practical.  For cast-in-place piles, a statement that the inside measurement checked the pay length, determined as above, is to be made.

3.        A layout drawing that shows the location of all piles in a structure and assigns a numbering system to the piles that matches the pile number shown in the pile log, CA-S-3 (Form BR-2-75)

4.        CA-S-3 (Form BR-2-75) and a copy of the pile layout should be submitted to the Office of Geotechnical Engineering.

508 Falsework and Forms

General

Location

Prior to the erection of the forms for each substructure unit, the Inspector should ensure that the Contractor is placing the forms in the correct location.  This should be accomplished by available methods that do not require the use of instruments.

Types and Use

Footing concrete may be placed against rock, hard shale, or sheeting.  All other concrete must be placed in substantial forms that are designed and constructed so that finished concrete will conform to plan lines and dimensions and will have a satisfactory surface.  Forms for exposed surfaces are to be made of acceptable materials that will produce a smooth surface with a minimum number of joints.  Acceptable materials include sheet plywood, fabricated metal forms, fabricated metal frames with plywood inserts, or dressed lumber of uniform thickness with a form liner of plywood, hardboard, or sheet metal.

Previously used form lumber and bent metal forms that will not produce an acceptable surface on concrete when stripped, regardless of finish specified, are to be rejected.  Exercise care to obtain as flush a fit as possible at panel joints.  When rustication grooves are required, panel joints should, if possible, be made to coincide.

The underside of a deck that cantilevers out from the fascia beam is considered an exposed surface and requires forms with smooth surfaces.  The underside of pier caps is considered an exposed surface and forms with smooth surfaces should be used and cut to fit neatly around columns or piles.

The inside of all forms are to be coated with a bond-breaker.  If the forms are not coated, and oiling is necessary, it should be done before placing the reinforcing steel, or preferably, before assembly of the forms.

Design

Forms must be adequately braced and provided with walers and form ties that are properly designed to maintain the proper dimension and alignment for the proposed height and rate of concrete placement.  Some suppliers of form ties specify the height of concrete in feet (meters) per hour that can be placed for their design.  All form ties and anchor bolts used for form support must be designed for removal of 2 inches (50 mm) in from the exposed surfaces of concrete.

When forming pier, intermediate of end diaphragms for prestressed or post tensioned concrete members, care must be taken to avoid damaging reinforcing steel, strands, or precast concrete. The Contractor should not place post installed anchors in these members. They should properly brace diaphragm forms externally or use approved form tie inserts cast into these members.

Incidental Work

Moldings for the 3/4-inch (19 mm) beveled edges and rustification grooves must be surfaced on all sides and be of uniform section.  The bevel strip should be nailed at sufficient intervals to completely fill a corner or contact the form for the full-length.  Rustification strips are fastened to the forms in such a manner that the molding will remain in contact with the concrete when the forms are stripped and will not be removed until the concrete has set sufficiently to avoid damage.

Weep holes through abutments and retaining walls are formed in such a manner as to obtain a smooth, circular opening.  To form the hole, metal such as downspouts or sonotube may be used and later removed, or noncorrodible rigid plastic pipe may be used and left in place, provided the gradient and inside diameter are in accordance with 508.03.

All scrap wood, dirt, and other foreign material, including ponded water, must be removed from within the forms prior to placing concrete.  If the forms are too deep or narrow to permit easy removal of foreign material from the top, a temporary opening should be left at the bottom for removal of foreign material.  When necessary, an opening must be provided for inspection.  Temporary openings must be made mortar tight after the forms have been cleaned and inspected.

Forms should be inspected for proper fit and for holes where leakage of cement paste may occur.  Openings must be corrected in order to close the hole and provide a smooth form surface.  Filler strips, plugs, and tin are commonly used to plug such openings.  Forms should be watched closely during the placing of the concrete and any leaks must be corrected immediately.

Verification of Dimensions

Before any concrete is placed, form dimensions should be measured for compliance with the plan requirements and approved change orders.  Measurements which result in concrete equal to or greater than plan dimensions are considered verified plan dimensions.  The measurements must be checked for compliance with the plan dimensions and then recorded and filed in the project records.  A statement that the dimensions have been checked and are in compliance with plan requirements is not acceptable verification.  The recording may consist of any of the three following methods:

1.        A tabulation of all the verified plan dimensions for simple shapes.

2.        A sketch on an appropriate form showing all the verified plan dimensions.

3.        The plan sheet for the structure unit with the verified dimensions checked thereon.

Whatever method is used, the Inspector should date and sign the sheet.  If checks are made on different days, dates should indicate the day each check was made.  If different inspectors check parts of the measurements, each should initial those checks that he has made.

If measurements are not in compliance, make correction and recheck the dimensions before the concrete may be placed.

Falsework (508.02)

Falsework is the system of temporary support of formwork for concrete members.  The falsework is to remain in place until the concrete members have attained required strength and are self-supporting.  This includes the system of supporting formwork for deck slabs and pier caps.

Falsework Working Drawings

For cast-in-place concrete slab bridges, the Contractor must submit a falsework working drawing per 501.05.B.3.  No superstructure concrete can be placed until the working drawing is received and the falsework conforms to the submitted working drawings. The Contractor may substitute elements of equal or greater strength if it does not involve a change in depth that effects elevations.  Any other deviations from the accepted working drawing that the Contractor desires, or that becomes necessary due to unforeseen conditions, must be covered by submission of a revised working drawing.

District Review of Falsework Working Drawings

Although ODOTs acceptance of falsework working drawings is not required, a review should be made at the project to ascertain that the existing conditions shown in the working drawing are representative of those found in the field. The absence of Department acceptance does not supersede the Engineer’s authority as defined in 105.01.

Falsework Camber

The maximum deflection permitted in the falsework of a slab bridge is specified in 508.02.  Camber equal to this deflection must be built into the falsework to compensate for falsework deflection.   Camber equal to 1/800 of the span must be built into the falsework to compensate for deflection of the slab after falsework is released.  Also, camber which conforms to the vertical curvature of the profile grade must be provided.

If unusual requirements for span of an existing road or channel or restrictions due to vertical clearance exist, contact the Office of Structural Engineering to evaluate acceptable site specific camber requirements.

Falsework Materials

Falsework members must be of the section and length shown on the submitted working drawings.  Members having a greater section modulus may be used; however, if this involved a change in depth and affects elevations, details of modifications should be included on a resubmission of the affected working drawing.

Steel members such as stringers must be in good condition.  They must not show loss of section through rusting, excessive weldments, or holes that would affect their strength.

Timber shall be sound and of the required size. Used timber that shows deterioration and stress cracks may not perform its function and must not be used.

Piling and Posts

Piling must be driven to the bearing called for on the submitted plans.  In order to determine the required blow count, it will be necessary for the Contractor to perform dynamic load testing. 

Consolidation of Wood

Allowance for consolidation of wood wedges and blocking must be provided.  Using rough-cut timber, an allowance of 1/16 inch (2 mm) for each contact surface will be necessary.

Independent Support

Where phased construction or adjacent concrete decks are separated by an open joint or closure pour, forms for the cantilevered edges of each slab must be supported independently from the adjacent structure.  This is necessary to avoid movement of the forms due to differential deflections during placing of the concrete.

The finishing machine must be supported by the structure on which the concrete is being placed and independent of any adjacent structure or support.  If it is not, the finishing machine will not move with the deck as the concrete is placed and can result in areas where the superstructure concrete is either too thick or too thin.

Closure Pour

Closure pours are normally specified during phased construction when the cross bracing or diaphragms between the phases are not in place prior to the placement of the superstructure concrete.  A closure pour is not to eliminate traffic vibration, but to allow differential deflection to take place between the phases when the superstructure concrete is placed.  In order to properly place the superstructure concrete, the closure pour should not be waived unless the deadload deflection that occurs when the superstructure concrete is placed is less than 1/4 inch.

Superimposed Concrete

Prior to placing sidewalks, safety curbs, or other superimposed concrete on the deck of a slab bridge, the falsework must be removed or released and allowed to deflect.

Removal of Falsework

For QC/QA Concrete, falsework may be removed when the conditions tabulated in the table of section 511.14-1A of the Construction and Material Specifications have been met. If QC/QA is not being used, falsework may be removed when the conditions tabulated in the table of section 511.14-1B have been met.  Any piling not removed must be cut off at least to the slope line or rip rap line of the bed of stream.

Documentation Requirements - 508 Falsework and Forms

1.        Received falsework working drawings submitted per 501.05.B.3 for slab deck bridges.

2.        Falsework constructed according to submitted drawings.

3.        Document bearing obtained and number of falsework piling.

4.        Number and size of bracing on falsework.

5.        Protection during cold weather.

6.        Forms oiled prior to steel placement.

509 Reinforcing Steel

Storage

All reinforcing steel received on the project must be stored off the ground and kept free from dirt, oil, and grease.  Often the Contractor will store the reinforcing steel on wood blocks or similar devices. If this is the method chosen by the Contractor to store the reinforcing steel off the ground, it is important that he use enough blocks to prevent the reinforcing steel from sagging and coming into contact with the ground.  The reinforcing steel must not be stored in a place where it will be damaged or bent by equipment or be located in the path of drainage.  If epoxy coated reinforcing steel is to be exposed to sunlight for more than 2 months, it needs be covered to protect the epoxy from UV breakdown. This requirement can be found in ASTM A775 which is incorporated by reference in section 709.00 of the C&MS.

Care of Material (509.03)

The reinforcing steel must be cleaned of all dirt, oil, and grease.  Oil or grease on the steel will seriously affect bond and must be removed with a solvent.  Many times dirt cannot be removed with water alone, but must be loosened with the use of a rag or brush before rinsing it off the reinforcing steel. If steel requires cleaning before being placed, it should be cleaned outside the forms.  Once reinforcing steel is placed in the forms, it is difficult to see the dirt, oil, or grease on the bottom side of the reinforcing steel.

Method of Placing (509.04)

Reinforcing steel should have a TE- 24 with the shipment. If the reinforcing steel does arrive without a TE -24 either the District Engineer of Test or the Office of Material Management should be notified.  Check conformance of the delivered bars’ length to plan specified length.  During placement, compare the fit of the reinforcing steel in the measured forms.  All steel required in any structure unit must be included in that unit.  Advance separation of the steel by structure units from prepared lists can preclude omissions.  Check the total number of bars of each bar mark placed for each concrete placement and spot-check the spacing of the reinforcing steel.   For the reinforcing steel that comprises the mats in a deck, the total number of bars is more important than extreme accuracy in the space between adjacent bars.

Clearances

Reinforcing steel must be located at the specified distance from the surface in order for reinforced concrete members to have the proper clearance.

Reinforcement shall be placed in the position shown on the plans and kept in that position while the concrete is being placed.  Attempting to position a reinforcing bar cage during or after the deposition of concrete is not permitted due to the fact that the consolidation of concrete around the perimeter of the reinforcing steel will be compromised. 

Bolsters or chairs should be used, or the cage should be assembled and wired so that the proper clearances are obtained before encasement.  The bolsters or chairs used to support reinforcing steel in slabs, beams, or girders must be spaced no more than 4 feet (1.2 m) apart both transversely and longitudinally.  This spacing is a maximum.  The Contractor needs to install enough supports to keep the reinforcing steel from experiencing substantial deflections induced from construction loads. 

When placing reinforcing dowels extending out of a footing, they must be located accurately so they will lap properly with the reinforcement in adjoining concrete.  This particularly applies to dowels for pier columns where the location of vertical column bars is specified.

Prior to placing concrete, it is important to check the clearance or cover over the surface of the reinforcing steel.  The clearance between the reinforcing steel and the surface of the concrete shall not be less than:

1.        2-1/4 to 2-1/2 inches (57 to 64 mm) between the top mat of the reinforcing steel and the deck surface. 

2.        1-1/2 inch (38 mm) between the bottom steel and the bottom of a cast-in-place deck. The bottom steel must be spaced from the forms, never from the beams.  The bolsters have a tendency to indent the forms and cause less than a 1-1/2 inch (38 mm) clearance.  A tolerance of 1/8 inch (3 mm) plus or minus in bottom steel clearance is permitted.

3.        3 inches (75 mm) at the face of footings placed against rock or earth.

4.        2-1/2 inches (65 mm) to the top of sidewalks.

5.        2 inches (50 mm) at all other surfaces.

A piece of wood approximately 2 inches (51 mm) long with accurate side dimensions of 1-3/8 inches (35 mm) and 1-5/8 inches (41 mm) is recommended to check clearances from the forms for the bottom reinforcing steel.

Transverse reinforcing bars, fabricated slightly longer than plan, can result in less than the plan clearance to the fascia form.  Where the transverse line of steel is made of more than one bar, any overrun can be taken in the lapped splices.  For narrower decks where the line is a single bar, removal of any extra length that will not provide a 1-inch (25 mm) minimum clearance is required.

Tying Reinforcing Steel

Reinforcing steel must sufficiently be tied together so that each bar retains its proper position after encasement.  When workers are on the steel, additional tying is necessary to meet this requirement.  Bars in the superstructure must be tied at all intersections except where spacing is less than 1 foot (0.3 m) in each direction.  In that case, alternate intersections shall be tied.  This is an area where additional inspection may be required since many times the Contractor fails to adequately tie these bars.  When the Contractor utilizes a tie wire gun to tie bridge deck reinforcing, it has been observed that the ties loosen or break under the repetitive loads invoked by the construction activities.  

Welding

Welding on reinforcing steel is prohibited.  This is due to the fact that not only will the welding damage the epoxy coating, but will reduce the diameter of the reinforcing steel at the point where it has been welded.

Splicing (509.07)

In lieu of lap splicing, reinforcing steel will be spliced with the use of mechanical connectors.  There are various types of mechanical connectors that include:

1.        Steel castings that have grout injected.

2.        Crimp-type that are pressure clamped onto the reinforcing with hydraulic jaws.

3.        Coupling-type splices that have threads cut into the end of the rebar.

4.        Coupling-type splices where the rebar ends have been offset pressed and the threads rolled into the end of the rebar.

5.        Cadweld where the ends of the rebar are butted together and a sleeve is placed over the ends.  The sleeve is then filled with molten metal and allowed to cool. This kind of coupler is not acceptable for epoxy coated steel.  

The most common type of mechanical connectors is the coupling type as described above in No. 3 and No. 4.  The mechanical connectors described in No. 3 should come with two shorter pieces of reinforcing steel that are lapped to the reinforcing steel that is to be spliced. These two pieces of reinforcing steel will be a larger diameter (if a splice for a No. 6 bar is required, the lap section sent with the coupling will be a No. 7 bar) because the thread cutting process reduces the cross-section area of the bar.

Number 14 and 18 (45 M and 55 M) bars are required to be spliced with accepted mechanical connectors. 

The mechanical connectors must provide 125 percent of the yield strength of the bar and be installed according to the manufacturer’s instructions.  Completed mechanical splices, including at least 18 inches of rebar on either side of the splice, should be sampled and submitted to the Office of Materials Management for testing.

Bar shall be lapped for a length equal to one and one-half turns when splices in spiral reinforcement are made.

Supports (509.08)

Reinforcement may be spaced by metal supports, plastic supports, or precast mortar blocks. Supports should be checked as soon as possible to determine that they will provide the proper clearance.  The bolsters or chairs used to support reinforcing steel in slabs, beams, or girders must be spaced no more than 4 feet (1.2 m) apart both transversely and longitudinally. This spacing is a maximum.  The Contractor needs to install enough supports to keep the reinforcing steel from experiencing substantial deflections induced from construction loads. If the Contractor uses plastic supports, they must conform to 709.15 and Supplement 1125. The concrete must be vibrated properly to ensure there are no voids in the concrete under these supports.

Epoxy Coated Reinforcing Steel (509.09)

When epoxy-coated reinforcing steel is specified, plastic-coated or epoxy-coated bar supports and tie wires are required.

Bars shall be carefully handled and installed so patching at the job site will be kept to a minimum.  It is not expected that the coated bars, when ready for concrete placement in final position, will be completely free of damaged areas.  However, numerous nicks and scrapes that expose the steel will not be allowed, regardless of the stage when they occur subsequent to coating in the plant.  All damage defined as significant damage must be patched. 

Significant damage is defined as any opening in the coating that exposes the steel and exceeds the following sizes.

1.        An area of 1/4 inch (6 mm) square or 1/4 inch (6 mm) diameter.

2.        An area approximately 1/8 inch (3 mm) square or 1/8 inch (3 mm) diameter if the opening is within 1/4 inch (6 mm) of another opening of the same or larger size, or a length of 6 inches (152 mm) in length, regardless of area.

All areas to be patched must first be cleaned to a near white metal, absolutely free of all rust and foreign material.

No concrete is to be placed against the patch until it has adequately cured.  Prior to placing concrete the patches should be checked to ensure that the patch has cured and is hard.

Method of Measurement (509.10) and Basis of Payment (509.11)

Verification

Reinforcing steel and any specified mechanical connectors are to be in place and accepted by the Engineer before any concrete is placed.  Record this approval in the daily diary.  The reinforcing steel and mechanical connectors in each structure unit are verified by a check-off inspection.  This verification may consist of a separately prepared list of all bars and mechanical connectors in each unit, listing the number of bars by bar mark or checked off the record plan sheets with the checks identified and validated.  With the exception of the mechanical connectors, all the lists and record plan sheets are summarized on the plan steel list that is verified by reference to them.

Pay Quantity for Reinforcing Steel

It is intended that the Contractor be paid for the weight of reinforcing steel shown in the plans and that no additional calculations are necessary.  

If the Contractor believes the pay weight, as shown on the plans, is in error, he is responsible to prove this discrepancy by recalculating the total weight for the entire reference number involved. He must submit his figures to the Engineer for review and approval. The number of pounds (kilograms) of reinforcing steel must be the actual number of pounds (kilograms) of the various sizes incorporated in the concrete as shown on the plans, completed and accepted.

In checking the calculations for the length of bent bars, the centerline length of the bar is the pay length.  This involves a deduction from the out-to-out dimension for bends that amounts to the following listed inches (mm) for the number bar shown in the table below.

The most commonly used spiral reinforcement consists of No. 4 (13M) bars on 30 inch (765) diameter with 1-1/2 additional turns of the spiral steel at each end.  The weight of the spiral steel is calculated by adding 15.5 pounds (7.0kg), which is the weight of the additional turns for both ends, to the sum arrived at by multiplying the length of the spiral cage times 13.9 pounds per feet (20.7 kg/m).  To determine the weight of spiral steel with diameters other than 30 inches, use Equation 509.1:

Equation 509.1 – Spiral Steel Weight

Where:

H = Length or height of spiral (ft)

D = Outside diameter of spiral (in)

When bars with standard hook ends are specified, the pay length allowed for hooked ends beyond the out-to-out dimension is not shown in the plans, but is shown in the specifications.  When checking the calculations for the length of bars with standard hook ends, a deduction must be made from the out-to-out dimension for bends that amount to the following listed inches (mm) for the number bar shown in the table below.  The fabricator may add additional length to the bars in order to facilitate bending. This additional length is not to be included in the pay length.

STD. BAR LENGTH DEDUCTIONS FOR COMMON BENDS – INCHES (mm)

BAR.

NO.

STANDARD BENDS (DEGREES)

45

90

135

180

#3 (10M)

¼ (6)

1 (25)

1 (25)

1 7/8 (48)

#4 (13M)

¼ (6)

1 (25)

1 ¼ (32)

2 ½ (64)

#5 (16M)

3/8 (10)

1 1/2 (38)

1 5/8 (41)

3 3/8 (79)

#6 (19M)

3/8 (10)

2 (50)

2 (51)

3 ¾ (95)

#7 (22M)

½ (13)

2  (50)

2 ¼ (57)

4 3/8 (111)

#8 (25M)

½ (13)

2 ½ (65)

2 ½ (64)

5 (127)

#9 (29M)

5/8 (16)

3 1/2 (90)

3 3/8 (86)

6 7/8 (175)

#10 (32M)

¾ (19)

4 (100)

3 ¾ (95)

7 ¾ (197)

#11 (36M)

¾ (19)

4 (100)

4 ¼ (108)

8 5/8 (219)

#14 (43M)

1 (25)

6 (150)

5 5/8 (143)

12 (305)

#18 (57M)

1 3/8 (35)

8 (200)

7 ½ (191)

15 ¾ (400)

Documentation Requirements - 509 Reinforcing Steel

1.        The bar markings, the number of, and the clearance maintained on all bars in a specific pour (C&MS book and Plans).

2.        In deck.

3.        The bar markings.

4.        The number used.

5.        Side, end, and bottom clearance being maintained.

6.        Document top clearance on dry run (deck pour).

7.        Document top clearance after final screed strike-off on day of pour (deck pour).

8.        Tie reinforcing bars as per 509.04.

9.        If required, calculate total weight of bars for payment.

10.     Make sure Mill Certifications are received in order to document that reinforcing steel is of domestic origin.

510 Dowel Holes

Materials (510.02)

Non-shrink, non-metallic grouts include polyester, vinyl ester, and epoxy grouts. 

Placement (510.04)

Note that when using cement grout, the interior surface of the hole needs to be damp, while use of non-shrink, non-metallic grout requires a dry hole.

It is necessary to use surface thermometers to determine the temperature of the concrete into which the dowels are to be inserted.  The specification requires this temperature to be at least 40 °F.

Documentation Requirements - 510 Dowel Holes

1.        Number, diameter, and depth of holes drilled.

2.        Type of grout used.

3.        Amount of cure time required prior to loading.  This is dependent on ambient temperature.

511 Concrete for Structures

Materials (511.02)

Item 511.02 requires all concrete above the ground line in a given substructure unit or all concrete for any given superstructure be made of aggregate of the same kind and color, except upon permission of the Engineer.

Concrete (511.03)

Concrete for structures will be Class QC 1, QC 2, QC 3, or QC 4, or as specified in the Contract documents. The mix design and control are outlined in Item 499 and in Supplement 1126, except when modified as specified. 

The Contractor has to submit, in writing, the Department accepted Job Mix Formula (JMF) to the Engineer, for a check for conformance to contract requirements, at least ten days before placing concrete.

Quality Control Requirements and Mass Concrete (511.04)

When the contract requires Quality Control/Quality Assurance, (QC/QA) Concrete, in addition to the JMF, the Contractor is required to submit a Quality Control Plan (QCP) for the work and perform quality control testing of the concrete as specified in C&MS 455. Also per C&MS 455, the Department or its representative will perform Quality Assurance sampling and testing as specified or as deemed necessary.

 For quality assurance, the Engineer will make acceptance test cylinders as follows:

1.        Structure over 20 foot span. A set of test cylinders from each 200 cubic yards of concrete or fraction thereof incorporated into the work each day.

2.        Structures of 20 foot span or less. At least one set of test cylinders for each 50 cubic yards of concrete.

The Contractor must provide a sealed, temperature controlled, Concrete Cylinder Curing Box (CCCB) capable of holding at least twelve 4-inch x 8-inch cylinders for both quality control and quality assurance cylinders.

Mass Concrete Requirements (511.04.A)

Mass Concrete is defined as concrete components with a minimum dimension of 5 feet. In C&MS 499, QC-4 is the designated class of concrete for Mass Concrete mix designs. In addition to submitting a mix design,  per C&MS 499.03 and Supplement 1126, a Quality Control Plan per C&MS 455, the Contractor is also required to submit a Thermal Control Plan (TCP) to the Engineer, for a check for conformance to contract requirements, at least ten days before placing concrete. The purpose of the TCP is for the Contractor to explain how they plan to prevent shrinkage cracking in Mass Concrete placements.

The TCP must control the placement of mass concrete so that:

1.        The highest maximum internal temperature in the concrete is not greater than 160 ºF.

2.        The maximum differential concrete temperature does not exceed  36 ºF.

over 28 days from the time of concrete placement.

The TCP shall include:

1.        Duration and method of curing.

2.        Procedures to control concrete temperature at the time of placement. The mix shall contain no frozen pieces of ice after blending and mixing components.

3.        Methods and equipment used for controlling temperature differentials.

4.        Temperature sensor types, locations and installation details. As a minimum, concrete temperatures shall be monitored at the calculated hottest location, on at least 2 outer faces, 2 corners, and top surfaces.

5.        Temperature monitoring and recording system; operation plan; recording and reporting plan with example output; and a remedial action plan.

6.        Criteria, (allowable air and concrete temperatures and time), for form removal to control the maximum temperature differential.

The Contractor may propose maximum differential temperature limits based on strength gain with time as an alternate to the maximum differential concrete temperature criteria.

All cracking of mass concrete where the differential temperatures exceed 36ºF is the responsibility of the Contractor.

The Contractor must monitor and document all temperature sensors during the cure period. If the maximum limit or differential temperature limits are exceeded, the Contractor must take immediate action to correct the problem and revise and resubmit the TCP. The Department will determine if the proposed repair methods are acceptable or if removal is required.

Mixing of Concrete (511.05)

Control

All concrete used in structures must contain 6 ± 2 percent entrained air as specified in 499.  An air determination should be made for each part of the structure. This determination should be made as early as possible on the first load of concrete.  For substructure concrete, as many additional air tests as necessary should be made to ensure required air content.  For superstructure concrete, an air test should be made for each load of concrete used.  Concrete containing less than the specified amount of air may have the air content increased by the addition of an air entrained agent and an additional 30 revolutions of the concrete mixer drum at mixing speed. 

Concrete that is pumped can lose air as the concrete passes through the pump.  Therefore, it is important that air tests be made at the point of placement, after the concrete passes through the pump.

Accepted chemical admixtures may be incorporated into concrete to improve workability and to extend the setting time.  Chemical admixtures must meet the requirement of 705.12 that specifies they meet the requirements of ASTM C 494 chemical admixtures.  These admixtures are as follows.

·         TYPE A - Water reducing

·         TYPE B - Retarding

·         TYPE C - Accelerating

·         TYPE D - Water reducing and retarding

·         TYPE E - Water reducing and accelerating

·         TYPE F - Water reducing, high range

·         TYPE G - Water reducing, high range, and retarding

The type of admixture is optional with the Contractor.  However, when the air temperature is 60 °F  (16 °C) or higher at the time of placement of superstructure concrete, and the span is over 20 feet (6.1 m), the addition of a Type B or D admixture is required.

Slump (511.06)

The slump of the workable concrete shall be maintained within the range specified in 499.03.  An occasional load exceeding the nominal slump, but within the maximum, may be used, provided immediate steps are taken to adjust the slump of succeeding loads.  Before concrete exceeding the nominal slump range may be used, the Contractor or supplier must take positive action to reduce the slump of following loads. 

Records

The results of the air tests together with yield tests are shown on the back of Form TE-45.  The Ready Mixed Concrete Plant Ticket must show the number of revolutions at mixing speed.  A mixer’s rated RPM for mixing speed and agitation speed will be listed with the operating data on the mixer.  The mixers must be checked to see that they are operating at the rated speeds.  The structure unit in which that load of concrete is placed should be noted on the ticket.  A full list of the required data to appear on a batch ticket is listed in Table 499.07-1.

Placing Concrete (511.07)

The Contractor must submit to the Engineer a description of proposed placing procedures. If the contract requires QC/QA Concrete, this procedure would be included in the QCP.

Advance Notice of Placing Concrete

The Contractor must notify the Engineer at least 24 hours in advance of placing concrete.  Review this provision with the Contractor near the start of work on a structure. This ensures a clear understanding regarding the stage of completed work necessary to permit inspection before approval to proceed.  The need for all or part of the 24 hours will depend on the amount of additional inspection required to ensure that the reinforcing steel has been properly placed and that the forms are in the correct location.

Placement Tolerances

The Contractor is required to place and finish concrete to the lines and grades shown in the plans. The concrete must provide coverage over or around reinforcing steel as described in 509.04. Table 511.07-1 lists placement tolerances from plan dimensions.

Evaporation Rate

In an effort to reduce or eliminate drying shrinkage cracks in the superstructure concrete, the concrete should not be placed when the evaporation rate of water from the freshly placed concrete is too high.  Use the graph (Figure 1) in C&MS Item 511.07 to check the evaporation rate.

The Contractor should check the evaporation rate immediately before the placement of superstructure concrete begins.  The evaporation rate should also be checked if there is a change in temperature, humidity, or wind speed during the placement of superstructure concrete. Wind speed can have the greatest effect on the evaporation rate; therefore, changes in wind speed should be more closely monitored.  Many times, during the summer months, it will be necessary to place superstructure concrete at night in order to comply with the evaporation rate limits. 

In addition to the evaporation rate, superstructure concrete is not allowed to be placed when the ambient air temperature is 85 °F (30 °C) or higher or is predicted to go above 85 °F (30 °C) during placement.  The temperature of the concrete is not allowed to exceed 95 °F (35 °C) during the mixing and placement.  Many times it is necessary for the Contractor to reduce the temperature of the mixing water and/or aggregates in order to control the temperature of the concrete.

Evaporation retardant is mostly water and its use is not permitted.  Be aware that evaporation retardants are also marketed as finishing agents, but under either name their use is prohibited.

Placement

Several methods may be used to convey the concrete to the forms.  Any method that ensures placement of concrete of the proper consistency without segregation is satisfactory.  Usually ready-mix trucks with open chutes, buckets, drop chutes, and concrete pumps are used to place substructure concrete.  Open chutes must be sloped sufficiently to allow concrete of the proper consistency to flow readily.  Drop chutes may be maneuvered to distribute the concrete, but the delivery end must be kept vertical.  Concrete is deposited as near as possible to its final position with as short of a vertical drops as practical but not over 5 feet (1.5 m).

Consolidation of concrete by the vibration method is required for structures.  Spud vibrators generally are used and should have a workman assigned exclusively to each vibrator.  The vibrator should be pushed into and pulled out of the freshly deposited concrete slowly and as vertical as possible.  For narrow sections, the vibrator may be applied to the sides of the forms or a form vibrator may be used.  Establish a pattern of placing and vibrating that provides practically horizontal surfaces and uniform vibrator coverage.  Generally a vibrator can consolidate concrete in approximately a 4-inch to 8-inch radius depending on the type of concrete.  Visual inspection of consolidation is a two-step process of one, seeing the surface of the concrete flatten out, and two, seeing air bubbles come to the surface within the vibration radius.  Therefore, a uniform coverage pattern must be used to ensure uniform consolidation.

Footings

Where concrete will be placed to bedrock, the rock should be free of mud and cleared of all loose rock or other accumulations.  Soil serving as the footing bottom should be sufficiently dry and stable so that it will not be interspersed in the concrete.

Concrete may occasionally be placed in water; however, with the exception of drilled shafts, concrete is not to be placed under water.  When concrete is placed in water, placement should begin in one corner of the forms and continue against the previously deposited concrete until full height of the footing is attained.  Full height should be carried forward, displacing the water ahead and out a small opening in the opposite corner of the forms.  Vibration of the concrete should be kept well back of the water.  Concrete must never be deposited in running water since it will cause separation of cement from the mixture. If pumping is controlling the water level, the pumping may be halted or reduced immediately after the concreting is complete, so that the water level rises slowly and inundates the footing to provide the cure.

When the plans require a concrete seal, or it becomes necessary for the Contractor to use a seal to stop the upward flow of water, the concrete must be deposited under water in a manner that minimizes separation of the cement.  This type of seal is sometimes referred to as a mud mat.  A concrete seal is deposited in a compact mass with a minimum of disturbance from the water it displaces.  When a tremie or concrete pump is used, the end of the pump or tremie hose or tube must be plugged prior to lowering into the water and kept filled during placement.  Failure to keep the tremie or pump filled with concrete during placement could result in water entering into the tremie tube or pump hose.  This will result in the cement being washed from the aggregate.  The Contractor’s plans for the mix and placement should be reviewed prior to the pour.  Where the Contractor elects to use a seal, it is his responsibility to choose a thickness and methods that produce satisfactory results.

Piers and Abutments

Concrete for backwalls above the approach slab seat shall not be placed until the abutments have been backfilled to within 2 feet (610 mm) of the bridge seat elevation.  

When expansion joints are involved, the backwall should not be placed until after the superstructure concrete is placed.  As the superstructure concrete is placed, the beams will grow in length as the camber decreases.  If the backwall is placed prior to placing the superstructure concrete, the required opening in the end dam will be lost as the beams grow in length.

The tops of backwalls that become roadway surface require special methods for setting the grade.  Although the recommended methods have been used to set the end dams, the elevations can be slightly off grade. Therefore, the tops of the end dams should not be used alone to project the grade for the backwall.  The preferred method of obtaining the correct grade is to place a 10-foot (3.05 m) straightedge as a screed supported on the superstructure concrete and the end dam.   The backwall can be struck to the proper grade.  Grade strips tacked to the backwall form that have their elevations established in a manner described above may be used to establish the grade.  In the event that the grade for the surface of concrete is not flush with the end dam edge bar, it should be finished to the grade established above and edged to a radius equal to the offset where it abuts the edge bar.

After the forms have been stripped from backwalls and before the approach slabs are placed, the top surface of concrete is subject to damage by spalling of the sharp edge on the approach slab side.  Covering the surface with a plank or any other method that will afford equal protection should be provided.

Concrete should never be deposited through closely spaced reinforcing steel where it may accumulate and take set prior to encasement or cause segregation of aggregate.  The bars, such as the top main bars in a pier cap, should temporarily be moved out of the path of the concrete or hopper until the concrete level has reached the vicinity of the bars and then reset.  If the plans require bearings for which anchor bolt holes will be drilled later, the bars must be reset accurately and checked with a template.

Bearing Seats

Bearing areas on abutments and piers must be finished accurately to the plan elevations in order that the deck may be placed on profile grade.  The elevations should be checked accurately when finished to correct possible errors and settlement of the forms containing the original marks.  Take elevations as soon as possible after completion of the substructure units and record them for future reference.

Bearing seats that are high or uneven must be leveled to the proper elevation by bush hammering or grinding and then smoothed with a thin film of Portland cement paste to fill the pitted surface.  Bearing seats that are over 1/8 inch (3 mm) low are leveled as described above and raised to the proper elevation by steel shims placed under the masonry plates. If elastomeric bearings are specified, steel shims should not be placed under the bearing.  In this case, consult the Office of Structural Engineering pertaining to the acceptability of the Contractor’s proposed method of correcting the bearing seat.

Where it is necessary to cut down the bearing area, the lowering is extended approximately 1 inch (25 mm) around the area of the masonry plate and carried full width to the face of the abutment or pier cap for drainage.

Pre-Pour Conference for Placing Concrete for Superstructures

Prior to the scheduled day for deck placement, preferably the day before, a conference should be held to review the plans and preparations for the pour (Forms CA-S-4 and CA-S-6).  The Contractor’s Superintendent and key personnel, together with the Engineer and available inspectors who will be involved, should attend.  At this time, the Superintendent should state his plan of operation, and agreement should be reached with the Engineer on all of the following:

7.        Provision for adequate concrete delivery to ensure continuous placing and to provide sufficient length of workable concrete for proper straight edging.  This includes the number of trucks assigned and an access route where ingress and egress will be maintained at all times.

8.        Spacing of the trucks, especially at the start and end, so that no load will be delayed unduly in discharging or will placing be delayed for lack of concrete.

9.        A system of communicating with the concrete plant to permit ready adjustments in the mix or delivery

10.     Proper tools and equipment on hand have been checked and are in good working order.  A finishing bridge must be used when the deck cannot be reached for proper finishing.

11.     A competent and experienced bridge superintendent who will be in charge and at least two experienced finishers.

12.     Factors that might determine the need for chemical admixtures are explained.

13.     Protection on hand in case of rain or low temperatures.

14.     For decks with hinges, and where it is planned to terminate a pour at the expansion joint over the hinge, concrete placement should proceed in the direction that will load the longer part of the hinged span first.  This will minimize the effects of unequal span loading, unless otherwise specified in the plans.

15.     Properly curing the concrete and placing the wet burlap in a timely manner.

Closure Pour

Many times a bridge deck will be constructed part width at a time to maintain traffic on a portion of the existing or completed structure. At times, an existing structure will be widened by adding at least two beam lines.  A closure pour will be used to account for the differential deflection that will occur between the portion of the deck that has already been placed and has yet to be placed.  This closure pour is important and should be performed.  A closure pour involves a strip of concrete several feet (a meter) or more wide that is not placed until after the deck concrete is placed in both phases.  It is placed the entire length of the deck between the two portions of deck.

When a closure pour is specified, the forms on the second phase of the deck yet to be placed must not be supported by the first phase that has been previously placed.  The reinforcing steel must not be spliced, and cross bracing shall not be placed between phases until the concrete in the second phase has been placed.

Immediately prior to placing the concrete in the closure pour, it is important that the cross bracing between the first two phases be completely installed.  At this time, it is acceptable to support the forms for the closure pour from the two completed adjacent phases.

Setting the Grade for Finishing the Deck

When finishing a deck, setting the grade correctly is paramount for placing a deck on profile grade.  A table of screed rail elevations is shown on the plans for composite box beam bridges, rolled beam, girder, and concrete I beam bridges. Screed elevations should be provided in the plans for all curb lines or deck edges, profile grade points, transverse grade-break lines and phased construction lines for the full length of the bridge. Bearing points, quarter span points, mid-span points and splice points, as well as any additional points required to meet a maximum spacing between points of 25’-0”, should be provided in the plans. Screed elevations above each beam/girder line are no longer required by the ODOT Bridge Design Manual due to the differential deflection between beam/girders. The amount of beam/girder deflection that occurs due to the wet weight of concrete at each screed cross-section will vary based on the span length of each beam/girder, the magnitude of concrete load applied to each beam/girder and the size of each beam/girder cross section.

Screed Elevations are control elevations for concrete deck finishing machines that represent the theoretical deck surface locations prior to deflections caused by deck concrete placement and other anticipated dead loads. Screed elevations are provided to ensure the bridge deck is completed to the correct elevations.

Top of Haunch Elevations represent the theoretical location of the bottom of the deck above the beam/girder haunch prior to deflections caused by deck placement and other anticipated dead loads. Elevations must be taken on the end dams and at every point on the beams required for setting the grade of the screed rail, including points over the piers. There should be no deflections at the bearing points over the piers and abutments, with the maximum deflections occurring at the mid-spans. The Haunch Height (Haunch Fill) equals the Top of Haunch Elevation (Deck Bottom) minus the surveyed Beam Top Elevation. These elevations provide the contractor the means to determine the proper haunch depths for setting deck falsework. See Figure 511.A.

Beam Row

Elev.

Rear Abut

¼ Pt

½ Pt

¾ Pt

Pier 1

A

Deck Bot

966.64

966.48

966.32

966.16

966.00

Beam Top

956.97

965.82

965.68

965.5

965.33

Haunch Ht

0.67

0.66

0.64

0.66

0.67

B

Deck Bot

966.42

Beam Top

965.77

Haunch Ht

0.65

C

Deck Bot

966.52

Beam Top

965.87

Haunch Ht

0.65

D

Deck Bot

966.42

Beam Top

965.76

Haunch Ht

.66

E

Deck Bot

966.64

966.48

966.32

966.16

966.00

Beam Top

965.97

965.82

965.66

965.50

965.33

Haunch Ht

0.67

0.66

.66

0.66

0.67

Table 511.A – Determining Haunch Height

This is an acceptable method of recording this information.

The Final Deck Surface Elevations shown in the plans represent the deck surface location after all anticipated dead load deflections have occurred. These elevations should line up with the approach slab and pavement elevations off of the bridge. Whenever the profile grade of the deck is adjusted, this must be considered when setting the grade for the approach slabs and pavement in order to provide a smooth transition. Even though it has not been necessary to adjust the grade, the as-built grade of the deck should be used to establish the grade of the approach slabs, since the actual dead load deflections may vary from the calculated deflections shown on the plans.

Figure 511.A – Deck Elevations and Deflections

Figure 511.B – Screed Points at curb lines, profile grade and grade- breaks

Figure 511.C – Top of Haunch Elevations in Non-Deflected (Unloaded) Position

Differential deflection should be built into the Camber Diagram.

Figure 511.D – Interior Deflection > Exterior Deflection

Will occur with addition of concrete weight. Do not adjust screed rails to increase deck and cover thickness at interior of deck.

Figure 511.E – Interior Deflection < Exterior Deflection

Will occur with addition of concrete weight. Do not adjust screed rails to decrease deck and cover thickness at interior of deck.

Superstructure Framing, Setting Falsework, Setting Screed Rails and Dry Run

The Contractor’s carpenter foreman should use the following procedure when setting the deck falsework, setting the screed rails, and performing the dry run with the Engineer:

1.        Ensure all superstructure framing, (e.g., each intermediate crossframe and diaphragm), is permanently fastened according to C&MS 513.26.

2.        Once beam/girder erection is complete, mark the elevation control locations on the top of the beam/girder flanges.

3.        At each control location, survey and record the top of beam/girder elevation

4.        Calculate the haunch depths at each control location as the difference between the plan Top of Haunch Elevation (Deck Bottom), and the surveyed Beam Top Elevation.

5.        Using the haunch depths and screed elevations, erect the deck falsework. The bottom deck form in the overhangs shall be set by subtracting the deck edge thickness from the nearest screed elevation.

6.        With the falsework in place, mark the screed elevation control locations on the surface of the falsework.

7.        Set the screed rail elevations at control locations given in the plans using the screed elevations provided. Intermediate rail elevations may be determined by stringline between plan specified screed locations.

8.        Once the finishing machine setup is complete, run the unit the full length of the screed rails and back using the machine’s weight to take out any “timber crunch” or formwork settlement. Reset screed rail as necessary.

9.        Locate the finishing machine at each screed rail control location with the carriage moved nearest the screed rail. Measure and record the screed rail elevation. The difference between rail elevations with and without the finishing machine represents the deflection due to the weight of the finishing machine. Each screed elevation should be adjusted upward by the measured deflection. Measured deflections of 0.25” or less may be ignored.

10.     Starting at the beginning of the pour, locate the finishing machine at each screed cross-section and center the paving carriage above the interior screed elevations (e.g. crown points, profile grade lines, etc.) Adjust the finishing machine crown such that the elevation of the bottom of the paving rollers equals the screed elevation at that location.

11.     Record the magnitude and direction of the crown adjustment necessary when moving the finishing machine from one screed cross-section to the next.

12.     During placement, when the vertical crown adjustment is 0.25” or less, the total crown adjustment shall be made at the midpoint between adjacent screed cross-sections. For greater total adjustments, half of the total adjustment shall be made at the first quarter point between adjacent screed cross-sections and half at the third quarter point between adjacent screed cross sections.

13.     Using the cross-slope adjustments noted for each screed cross section, move the carriage to locations above each beam/girder line and above each mid-bay. Measure and record the distance from the surface of the formwork to the paving rollers and verify concrete/rebar clearance.

14.     When the thickness or cover does not meet plan requirements, verify the following:

a)        Are screed rail elevations set properly?

b)       Are haunch depths correct?

c)        Are overhang thicknesses correct?

d)       Do crown point elevations match screed elevations?

e)        Were rail elevations adjusted for weight of machine?

f)         Are the reinforcing steel chairs set to the correct height?

g)        Is there a plan error for screed elevations?

15.     If each of the preceding items are in order, differential deflections between beams/girders in the screed cross section may be involved.

DO NOT adjust screed rail elevations.

Use CA-S-22 Dry Run Form as a template.

When a closure pour is specified, the designer assumes that the finished elevation of the existing deck is correct.  Due to conditions beyond his control or conditions he has overlooked, the finished elevation of the deck may not be as he assumed.  If this condition exists, it should be detected prior to placing the widened or second portion of the deck.  Therefore, prior to placing the widened or second portion of the deck, the Contractor should check the finished elevation of the existing portion of the deck to ensure that it is correct.  If it is determined that the finished elevation of the existing portion of the deck is not correct, the Office of Structural Engineering should be contacted for additional instructions.  

Slipform Construction of Bridge Railing (511.08)

In lieu of conventional forming, the Contractor may be permitted to slipform the parapets. This operation is accomplished with concrete that has a slump of around ±1 inch.

Prior to placing the concrete, the Contractor must take additional measures to tie the reinforcing steel in order to prevent it from dislocating during the slipforming operation. If these measures are not taken, the slipforming operation will cause the reinforcing steel to move out of its proper location.

Due to the low slump, many times the Contractor will attempt to add water to the mix as it comes down the chute from the concrete truck and enters into the hopper of the slipforming machine.  This is not allowed since it will result in concrete of inferior quality.

During the slipforming operation, small amounts of concrete will drop from the edge of the deck and onto the surface below the bridge.  If the slipforming operation takes place directly over a traveled roadway, the Contractor should furnish all necessary platforms to protect the traffic from falling concrete.  These platforms will allow access to complete the finishing operation and facilitate inspector access.

The Contractor should take steps to ensure that the finished concrete meets the specified tolerances.  These steps should include adequately tying the reinforcing steel, determining the proper slump, and properly setting up the slipforming machine.  Failure to meet the specified tolerances could result in the rejection of the parapet.

Any defects such as cracking, tearing, or honeycombing should be repaired immediately.  Occasionally, when repairing defects, the Contractor will not completely fill the defect with concrete, but will only bridge over the defect by placing the concrete on the surface of the parapet.  This is not acceptable. The Contractor should take steps to ensure that the defect is completely filled with concrete.

Normally, a small amount of hand finishing is required after the concrete has been formed.  Hand finishing can be difficult due to the low slump of the concrete.  To facilitate finishing the concrete, many times the Contractor will sprinkle water or evaporation retardant onto the surface of the concrete.  The use of these substances to aid in hand finishing is not allowed since it will only result in a surface that is subject to scaling in the future. The contractor should not broom finish the surface.

After the concrete has initially set, it is important to saw the control joints to the plan depth into the parapet as soon as possible.  Any delay in performing this operation will result in additional shrinkage cracks in the parapet.

Construction Joints (511.09)

The surface of construction joints should be even and have coarse texture such as produced by a wood float on fresh concrete.  Vibrated concrete with a closed level surface is satisfactory.  Where the construction joint terminates at an offset in the concrete surface, such as between the fascias of the deck slab and the sidewalk, the joint should be finished neatly at the corner with a wood float.

Transverse joints as permitted in 511.09, or longitudinal construction joints placed in deck slabs of steel beam or girder bridges, are constructed with keys located between the reinforcing mats and having a depth of 3/4 inch (19 mm).  If the Contractor desires a longitudinal construction joint due to an excessive slab width and because it is not provided by the plans or specifications, the request must be submitted to the Office of Structural Engineering for review.

Work Stoppage (511.10)

During the placing of a deck, unexpected difficulties may occur that halt further placing.  These may be a sudden shower, a breakdown in the concrete plant or the finishing machine, or other unforeseen interruptions.

When a shower occurs, no manipulation of concrete should be performed other than channeling the concrete that was last deposited so that water will not pond on the concrete and run back on the finished or partially finished surface.  The textured surface should be covered with the curing material as rapidly as possible.  Non-textured surfaces should be covered with polyethylene sheeting.  After the shower, all ponded water should be removed from the concrete and out through the forms before resuming placing and finishing operations.  The last surface covered with the curing material should be inspected. If it has been marred, the texture should be restored.

Investigate stoppages immediately.  If it is found that it will not allow resumption of concrete placing in sufficient time, a bulkhead must be placed immediately.  If practical, the location should not be over a pier.  The emergency bulkhead may consist of a wood strip laid across the top of the longitudinal reinforcing bars.  This strip should be as deep as the plan cover, usually 2-1/2 inches (64 mm).  Kickers can be used to secure the strip or shims inserted between the bars in order to obtain proper crown and grade.  The concrete below the wood strip should be compacted to approximately a 45 degree slope and all excess removed as far from the joint as possible and disposed of before it hardens.  After the concrete has set, but still fractures easily, the bottom edge should be broken to provide a vertical face below the bottom reinforcing steel.  This may be accomplished with a pry bar prying up from the forms. Exercise care to ensure the surface of the forms is not damaged.  See Figure 511.G - Emergency Bulkhead.

Figure 511.F – Emergency Bulkhead

Depositing and Curing Concrete During Cold Weather (511.12)

Heated concrete and protection must be provided whenever concrete is placed at an atmospheric temperature of 32 °F (0 °C) or lower or whenever weather forecasts predict temperature below 32 °F (0 °C) within the curing period.  Concrete must not be placed in contact with material having a temperature of less than 32 °F (0 °C).

The official U.S. Weather Bureau forecast for any curing period generally can be obtained from the District Office.  This information also can be obtained from some local airports and radio stations.

When the 5-day weather forecast does not predict 32 °F (0 °C) or lower temperatures at any time during the period, the Contractor should not be required to erect enclosures or to use insulated forms.  However, during the fall, winter, and spring, adequate material and equipment should be on hand to provide for unpredicted temperatures below 32 °F (0 °C).

To ensure freedom from freezing until protection can be established, the temperature of concrete should not be less than the minimum of 50 °F (10 °C) specified, but should not exceed 90 °F (32 °C) maximum.  Concrete placed at low temperatures above freezing develop higher ultimate strength and greater durability than concrete placed at higher temperatures.  Higher temperatures require more mixing water, cause slump loss, possible quick setting, and increase thermal shrinkage.  Rapid moisture loss from hot, exposed concrete surfaces may cause plastic shrinkage cracks.  It is recommended that the temperatures of fresh concrete, as placed, be kept as close to the 50 °F (10 °C) minimum temperatures as practicable.  When the air temperature is 32 °F (0 °C) or lower, it is necessary to raise the temperature of the concrete by heating the mixing water or aggregate or both.  The concrete must be protected from freezing, and specified curing temperatures must be maintained by a heated enclosure, insulated forms, or by either of these in combination with flooding.

Decks slabs less than 10 inches (254 mm) thick must be protected from freezing, and specified temperatures maintained for the curing period by a heated enclosure.

Arrangements for covering and insulating newly-placed concrete must be made in advance of placement and should be adequate to maintain the specification temperature in all parts of the concrete.

During the first few days which require protection, most of the hydration heat of the hardening cement is developed. As a result, if heat generated in the concrete is adequately conserved, outside heat generally is not required to maintain concrete at the correct temperature.  This heat may be conserved by using insulating blankets and insulated forms where repeated reuse of forms makes this practical. Outside temperatures at concrete walls, piers, abutments, or slabs above ground may be protected with insulation under various conditions (see chart to follow).  On work where protection by insulation is permitted, project personnel should check the protection proposed by the Contractor and be reasonably sure that the proposed insulation is adequate for the expected exposure before concrete placement is permitted to begin.

The application of insulation should be as follows:

1.        Blanket insulation is applied tightly against wood forms with nailing flanges extending out from the blankets so they can be stapled or battened to the sides of the framing.  Seal the ends of the blankets by removing a portion of the mat and stapling or battening the blanket to headers to exclude air and moisture.  Corners and angles are most vulnerable.  Take extreme care to ensure they are well insulated and the insulation is held firmly in place.

2.        In case of steel forms, the insulation should be applied tightly against the form and held securely with the ends sealed to exclude air and moisture.

3.        Where practicable, the insulation or insulated form should overlay any cold concrete previously placed by at least 1 foot.

4.        Any tears in the liner are to be repaired immediately with accepted waterproof material.

5.        Where tie rods extend through an insulated form, a plywood washer, approximately 3/4 × 6 × 6 inches (19 x 150 x 150 mm), should be placed on top of the insulation blanket and secured in a satisfactory manner.

6.        The tops of all pours must be covered with insulating blankets, except for areas around protruding reinforcing bars that may be insulated with straw or wrapped with insulation blankets.  Waterproof covers should be used to cover the top of such pours, as required by specifications.

7.        Protective enclosures may be constructed of canvas, plywood, polyethylene, plastic, etc. in such a manner that will maintain uniform temperatures and allow free circulation to the warmed air.

8.        For the underside of deck slabs, 3/4 inch (19 mm) plywood forms have an equivalent thickness of 0.6 inch (16 mm) and will provide protection of 32 °F (0 °C) minimum air temperature.

9.        Close packed straw under canvas may be considered a loose fill type if wind is kept out of the straw.  The insulating value of dead air space greater than about 1/2 inch (13 mm) thick does not change greatly with increasing thickness.

Heated Enclosure (511.12.A)

When salamanders or other heaters supply heat, local drying and burning of the forms may result and necessitate moving or adjustment of the setup.  Regular observance of the forms and burlap should be made to ensure that the concrete is kept wet for the duration of the curing period, as required in 511.14.  Combustion type heating units shall be vented from the enclosure to preclude damaging fresh concrete. The enclosure should surround the top, sides, and bottom of the concrete to be placed during cold weather.

Temperature Control

Thermometers for use in enclosures should be the high-low recording type and be furnished by the Contractor.  If the enclosure is long or high, more than one thermometer may be required.  The readings in the morning and the afternoon normally represent the low and high temperature respectively; carefully select the time when the high-low recording thermometers are checked.

When insulated forms are used, the thermometer must be furnished and installed by the Contractor.  They must be capable of indicating surface temperature of the concrete.  In case of a tall section, such as pier shafts or retaining walls, more than one thermometer will be required because of the temperature gradient.  Temperatures should be read twice daily for high and low readings.  When insulated forms are used, temperature of concrete will cause a lag in the temperature change of the surrounding air.  Time of observance need not be as selective for representing the high and low, but is used to indicate a trend that may require venting of the forms or erecting an enclosure.  When venting of a vertical form is necessary, it should be raised slightly at the bottom to create a chimney effect.

The temperature record must include the required temperature readings for the entire curing period.  Outside air temperatures may be local reported temperatures.

Temperature and control methods used, as well as temperature readings, must be recorded on the Inspector’s Daily Report.

Cold Weather Curing Time

To fulfill the curing requirements for concrete placed in cold weather, the surface temperature must be maintained as specified in 511.14 or be exposed to ambient air temperatures no less than 50 °F (10 °C) for 5 days.

In case any day’s temperature readings fall below the minimum specified, the duration of heating must be extended to provide the required number of days.  In case of loss or breakage of thermometers, replacements or other provisions must be made to provide a complete record.

Removal of Forms (511.13)

Falsework must not be removed until after the time-temperature requirements of 511.14 are met or satisfactory beam tests are attained.  During cold weather, forms are to be removed after the curing period in such a manner that the temperature of the concrete does not drop more than 20 °F (7 °C) in any 24-hour period.

Note 1 in Tables 511.14-1A and B states that span is defined as the horizontal distance between faces of the supporting elements when measured parallel to the primary reinforcements.  For slab deck bridges, the primary steel runs longitudinally down the deck.  For beam supported structures, the primary steel runs transversely across the deck. 

Curbs and Parapets

Forms for curbs and parapets should be observed carefully for condition of surface, flush fit of panel joints, proper installation of bevel strips, and visual and measured alignment and elevation.   Adequate form supports should be provided to ensure proper position of concrete during and after placement.  Surface rubbing does not justify the use of inferior forms or lack of adequate supports.

When expansion devices are used to allow for bridge deck expansion, more open space for expansion must be provided in the curb and parapet than is required for expansion devices.  Where conduits cross this opening, give special attention to clearance for expansion fittings to ensure free movement of the deck.

Transverse joints may be placed in the sidewalk or curb section near the center of any span.

Curing and Loading (511.14)

Curing is governed by 511.14 that requires either Method A, Water Curing or Method B, Membrane Curing.  Curing time is 7 days. No curing is required for surfaces covered by forms for the duration of the curing period.  Concrete that will be overlaid with concrete or sealed, as well as all superstructure concrete, must be cured in accordance with Method A, Water Curing.  The top surface of superstructure deck concrete must be cured for 7 days in accordance to Method A and then cured within 12 hours in accordance with Method B. Do not shorten the minimum required Method A curing time regardless of strength gain.

The curing material must be applied as soon as possible to avoid cracking of the concrete.  Application of the curing material should be applied immediately after the finishing operation is complete.

When it is necessary to work on concrete during the curing period, such as placing deck concrete adjacent to a construction joint, only the area immediately adjacent to the joint should be exposed and the remaining area protected from damage by the workers.  Plywood sheets may be used for protection.  The exposed area should be kept moistened until adjacent work is complete, after that, the cover should be restored and normal cure resumed.

Floor forms provide the cure for the underside of the slab and are not to be removed before the end of the curing period.

Method A, Water Curing (511.14.A)

When two thicknesses of burlap are used to water cure the concrete, they should be kept wet by the continuous application of water from soaker hoses or other sprinkling devices during the required period.  In lieu of continual sprinkling devices, white polyethylene sheeting or wet plastic coated blankets may be used to cover the concrete.

On bridge decks, a single layer of wet burlap is kept wet by a continuous application of water and covered by white polyethylene. The polyethylene should be placed transversely.  The edges should be lapped and held securely to maintain a moisture seal.  The curb area may be covered with a longitudinal strip that is held securely to the fascia form and laps the transverse strips.  A continuous batten may be used to seal the blanket to the form and reinforcing bars may be laid on the laps to make the seal.  Check areas suspected of having the seal broken during subsequent work or weather disturbances. If these areas are found to be drying out, soak the burlap and reseal the white polyethylene.

Plastic-coated blankets must be inspected prior to use to ensure that they are sound and will retain the moisture required to cure the concrete.  All holes and tears must be repaired so that they are watertight.  The material should be rejected if defects are numerous and repairs are questionable or if the plastic coating has cracked from aging.

Burlap and plastic-coated blankets must be thoroughly soaked with water prior to placing on the surface of the concrete.  Dry material placed on the surface of the concrete will draw moisture out. This will increase the chances of drying shrinkage cracks.  If new burlap is used, extra measures may need to be taken to ensure that it is properly soaked since it doesn’t soak up water as well as used burlap.  If burlap to be soaked is delivered to the project in a tightly wrapped condition, it should be loosened to allow the penetration of water.

Method B, Membrane Curing (511.14.B)

The concrete curing membrane is white-pigmented material meeting specifications 705.07.  The material may be either Type 1 (clear or translucent without dye) or Type-D (clear or translucent with fugitive dye).

The membrane should be applied in one or more separate coats by spraying a fine mist at a uniform application rate of one gallon per 200 square feet (70.3 square meters) of surface.  The rate of application is controlled by laying out in advance, on the surface to be cured, an area that will be properly covered by the number of gallons of compound in the spray container.  The procedure helps ensure that the membrane is applied at not less than the required rate.

Loading Requirements for QC/QA Concrete

See Table 511.14-1 in C&MS 511. Falsework may be removed from any span and all piers caps, and the concrete open to traffic when the compressive strength of sample cylinders is greater than or equal to 0.85 percent f’c or the flexural strength of sample beam is greater than or equal to 650 psi. Per Supplement 1098, the maturity curve method may be used for determining strength of the concrete. Do not shorten the minimum required Method A curing time regardless of strength gain. When placing concrete for a superstructure between October 15 and March 15, open the deck no sooner than 30 days after placement.

Loading Requirements for Non QC/QA Concrete

See Table 511.14-2 in C&MS 511.No traffic is to be permitted on a structure until the concrete has attained the age specified in 511.14.  For all spans, this is 14 days without a beam test or 7 days with satisfactory beam test. Do not shorten the minimum required Method A curing time regardless of strength gain. When placing concrete for a superstructure between October 15 and March 15, open the deck no sooner than 30 days after placement.

Loading of Completed Structure Units

No load is to be applied or work conducted that will damage new concrete.  This applies to loading or work on any part of the structure that will, in the opinion of the Engineer, cause damage.  Usually this criterion will permit work on a footing after 36 hours (or sooner) with a successful beam test, of normal curing, where bending stresses will not occur.

Surface Finish (511.15)

Patching

Shortly after the removal of forms, all cavities produced by form ties and all other holes, honeycomb spots, broken corners or edges, and other defects (except air bubble holes that may be filled by grout cleaning) must be cleaned. After being saturated with water, all cavities shall be completely filled, pointed, and trued with a mortar of the same proportions used in the concrete being finished.

On all exposed surfaces, all fins and irregular projections must be removed with a stone or power grinder, taking care to avoid contrasting surface textures.  Sufficient white cement must be substituted for the regular cement in the filling of holes and other corrective work to produce a finished surface of the same color as the surrounding concrete.

If shown on the plans, exposed surfaces that have an appearance not satisfactory to the Engineer shall be grout cleaned in a manner satisfactory to the Engineer.

The Contractor should be advised that it will be necessary to use good formwork to obtain satisfactory surfaces.

Grout Cleaning (511.15.A)

Grout cleaning shall be performed as outlined in 511.15.

Rubbed Finish (511.15.B)

When specified on the plans, rubbing shall be performed as outlined in 511.15.

Forms should be removed within 2 days after the concrete is placed.  Exceptions are the slab fascia form on which other fascia forms are set and wall forms that overlap a joint. If parapets are placed in cold weather, make provisions to remove forms and begin surface finishing on the day following placing, while maintaining a minimum temperature of 50 °F (10 °C), or postpone the placing of parapets until weather conditions are suitable for proper performance.

Roadway Finish (511.16)

Machine Finishing

A machine finish is required, except for small bridges where the Engineer may waive the requirement. Mechanized finishing machines are preferred to hand finishing methods for both consistency of surface finish and economics. The finishing machine must be self-propelled with forward and reverse drive. Mechanized finishing machines are comprised of fabricated truss sections pinned together to span the bridge deck width to be paved. The truss spans are supported at each end on a set of wheels, called “bogies,” which ride along the length of the bridge on screed rails. Suspended below the truss is a finishing head, called a “carriage,” which levels, compacts, vibrates and finishes the concrete. The machine shall have two rotating rollers, leveling augers and either a vibrating pan or vibrating rollers. See Figure 511.H. Field verify that the vibrating frequency of the pans or rollers is between 1,500 and 5,000 pulses per minute. The contractor must supply the instrument to check the frequency. The roller fins should not protrude more than 1/4 inch from the roller. Protruding fins can mechanically depress the aggregate too far from the surface of the concrete. The Contractor should detail the method used to support the machine on the deck and the complete procedure for placing the slab and submit to the Engineer for review.  Supports for the riding rails must be equipped to handle the weight of the machine in order to avoid failure or any vertical deflection.  The concrete handling, placing, and finishing procedure should be planned to ensure that the concrete will be placed and struck off with a minimum of manipulation and at a sufficient rate in order to provide workable concrete in an area adequate for proper, final hand finishing.  Success of the Contractor’s procedure on previous decks should be considered.

                                                                   Pin Connection

Screed Rail with Bogies (wheels)                     Carriage with rollers & augers

Figure 511.G – Finishing Machine    

For transverse machines, the screed should be assembled or adjusted to the required crown established from a taut line while suspended in the same manner as it will be in operation.

Prior to ordering concrete, and after the finishing machine has been made ready, make a dry run over the entire deck.  Check slab thickness and reinforcing steel cover along with crown conformance to both end dams and expansion joints.  If the rate of crown varies, and the machine can be adjusted during operation, the required crown should be determined at regular intervals not exceeding 25 feet (7.62 m), the required increment of adjustment established and the location referenced on the side of the bridge.

Plan dimensions for deck thickness, the reinforcing of steel cover which was verified during the dry run, and the witnessing of screed adjustments to the required crown must be recorded in the project records.  A last-minute check that form dimensions and reinforcement have been verified and documented should be made at this time on the Inspector’s Daily Report. Use CA-S-22 Dry Run Form as a template.

Finishing machines can be placed such that the truss sections are skewed with respect to the screed rails. This orientation allows for concrete placement parallel to the substructure skew as required by the C&MS 511. For skew angles of 15 degrees and greater, the finishing machine can be skewed to within 5 degrees of the plan specified skew angle. See Figure 511.I.

The carriage can also be skewed with respect to the truss sections. This feature allows the carriage to finish the concrete transverse to the bridge when the truss sections are placed at some other orientation (e.g., parallel to the substructure skew). In order to ensure a proper finish at transverse grade breaks (e.g., crown points), the carriage should always be oriented to finish the concrete transverse to the bridge. A special length truss section insert is required above the grade break locations such that the grade break line lies directly below opposite corners of the section. For skewed bridges without transverse grade breaks, skewing the carriage with respect to the truss sections is not required. The finishing machines can be hinged at the pin connections between truss sections in order to provide transverse grade breaks (e.g., crown points).

Paving Direction

Figure 511.H – Finishing machine oriented with skew

Although proper measurements made during the dry run should ensure plan dimensions, check measurements after the concrete is struck to grade in order to verify that the machine is still in adjustment and reinforcing steel remains in place.  Slab thickness measurements can be obtained by probing with a 1/4-inch-straight wire (6 mm)  and the cover over re-steel with a 90 degree bent wire of the same size.  These measurements should be taken shortly after the start of the finishing operation, and periodically thereafter, or when an area appears questionable.  Wide, flat sections such as super elevated slopes are questionable and must be checked.  The probing should be performed in plastic concrete where it will be easier to close the void.

Some cover checks are required; however, they do not need to be as numerous as the depth checks that also reflect cover.  It is recommended that as many depth checks as possible be made as time permits.  A statement should be entered in the project records indicating that check measurements have been made and conform to plan dimensions. If localized areas do not conform to plan dimensions, they should be noted, and any corrective action documented.

During operation, a uniform head of concrete should be maintained along the full length of the screed.  Screeds should be lifted from the surface when not in use.  During operation, only the operator is permitted on the machine.  The machine should continually be in operation as long as practical and the concrete placing procedure should not exceed the speed of the machine.

Tracking or walking in the screeded surface is not tolerated.

Final Finishing                                                   

It is imperative that final finishing follow immediately behind the finishing machine.  If this final finishing should fall behind, the rate of concrete placement should be reduced.

The construction joint surface under the sidewalk or the safety curb should not be used as a place for finishers to stand or as a passageway for workers.  Planks may be placed on the sidewalk reinforcement providing sufficient additional ties and braces are used if necessary to obtain a rigid framework that will not disturb the bond of the stirrups.

Minor surface irregularities left after screeding can be corrected with long handled floats.  This operation should be held to a minimum and any major irregularities encountered should be corrected by the use of a straightedge.  Use of water, evaporation retardants, or finishing agents on the surface of the concrete to facilitate finishing is not permitted.  If a Contractor adds water by continually washing his tools, require that they use a towel to dry the tools prior to reuse.

Bridge Deck Grooving (511.17)

The deck surface must be textured by using a broom to provide a surface satisfactory to the Engineer. The broom must produce a uniform, gritty texture in either the longitudinal or transverse direction.  The texturing should take place as the pour progresses after other finishing operations have been completed.  Note: If the concrete tears or “mud balls” are produced on the surface, the Contractor needs to apply less pressure to the broom or wait a few minutes until the concrete has begun to set.

After the water curing of the concrete is complete, and either before applying curing compound, or some period after applying curing compound, and before opening the bridge to traffic, longitudinal grooves, parallel to the bridge centerline, must be sawed into the surface of the deck. Apply curing compound within 12 hours after grooving the deck. The grooves must be sawed in a continuous, uniform pattern spaced at 3/4 inch minus 1/4 inch or plus 0 (19 mm minus 6mm or plus 0) and must be approximately 0.15 inch (4 mm) deep and 0.10 inch (3 mm) wide.  Grooves must be within 9 to 12 inches from devices such as scuppers or expansion joints.  On skewed bridges, in order to accommodate the equipment used to saw the grooves, the grooves must be sawed from 2 inches to 2 feet from the expansion joint.  This results in grooves with a staggered or stepped appearance. Maintain a minimum clearance of 9 inches (220 mm) to a maximum of 30 inches (750 mm) clearance between the grooves and the curb or parapet toe. However, at no point shall un-grooved portions of deck extend beyond edge line and into the temporary or permanent travelled lanes.

For staged, or phase bridge deck work, the grooves must be sawed parallel to the final, permanent bridge centerline. If the different stages or phases of the bridge deck work occur within one construction season, any stage opened to traffic shall receive an interim coarse broom finish during placement. Then the longitudinal grooves are sawed after the final stage. The interim broom finish will not be allowed as a surface texture when opened to traffic over a winter season. Longitudinal grooves must be sawed in the deck prior to opening to traffic for a winter season.

For bridge decks that widen from one end to the other, the longitudinal grooves must be sawed parallel to the centerline of the roadway. On the side of the bridge that widens, saw the longitudinal grooves to follow the edge line. Saw longitudinal grooves in the gore areas, avoiding the overlapping of grooves.

Sidewalk Finish (511.18)

Float Finish

Concrete for sidewalks, safety curbs, and tops of substructure units are struck off with a template and finished with a float to produce a sandy texture.

Sealing Joints and Cracks (511.19) 

After curing, all cracks, transverse and longitudinal joints in the deck, joints between the concrete deck and steel end dams, and joints between the concrete deck and safety curbs, barriers and parapets must be sealed with high molecular weight methacrylate (HMWM) prior to opening the deck to traffic.

Compressive Strength (511.20) 

Sample and test concrete strength according to C&MS 511.04.

Concrete Requiring QC/QA

When the bid item requires QC/QA, the Engineer will evaluate the QC compressive test sublot results according to Supplement 1127 to determine pay factors for structure concrete. 

If a single test result for compressive strength of a sublot of concrete is found to be less than 88 percent f’c, the Engineer will determine the location for evaluating the strength of the sublot represented by the low compressive strength concrete. Nondestructive testing or coring will be performed at such locations. If the reported nondestructive test results are greater than the specified f’c, the Engineer will accept the concrete and use the original cylinder results for calculating the compressive strength pay factor (PFc). If coring is performed, the core results will be used in place of the original cylinder results for pay factor determination.

If the nondestructive test results are less than the specified f’c, the concrete must be cored. The Engineer will determine the locations for the required concrete coring by the contractor for testing by the Department. The contractor must patch core holes with approved patching material. If the core results are above 88 percent f’c, the core strength results will be used for calculating the compressive strength pay factor (PFc).

If the core results indicate that the compressive strength of the concrete is below 88 percent  f’c, the Contractor must submit a plan for corrective action to the Engineer for approval. If the corrective plan is not approved, the Engineer will require the Contractor to:

1.        Remove and replace the unacceptable concrete that the sublot represents and retest the new sublot at no cost to the Department or

2.       Leave the unacceptable material in place and be paid for the sublot with a pay factor of 0.75.

If three or more sublot compressive strength acceptance test results are less than f’c, but greater than 88 percent f’c, the Engineer will require an investigation by the contractor of the reasons for the consistent low strengths. No additional placements of the concrete JMF will be made .until the investigation is completed to the satisfaction of the Engineer. The investigation should include all facets of the concrete operation including batching, mixing, delivery, clean up, sampling, testing, quality control plan, etc.  If the Engineer is unsatisfied with the results of the investigation, the JMF and the quality control plan will become not approved. The Contractor will have to develop and submit a new JMF and quality control plan conforming to the requirements of Supplement 1126, C&MS 499.03 and C&MS 511.04.  Pay factors under C&MS 511.22 for these low strength sublots will be based on the original reported cylinder strengths.

Concrete Not Requiring QC/QA

When the bid item does not require QC/QA, the Engineer will evaluate the strength results following the requirements of Table 511.22-2 and as follows:

1.        If a single compressive strength test result is less than f’c, the material will be considered unacceptable material and the Department will determine acceptance according to C&MS 106.07.

2.        If three or more compressive strength test results are less than f’c, the Contractor will be required to perform an investigation of the reasons for the consistent low strengths. No additional placements of the concrete JMF will be made until the investigation is completed to the satisfaction of the Engineer. The investigation should include all facets of the concrete operation, including batching, mixing, delivery, cleanup, sampling, testing, etc.  If the Engineer is unsatisfied with the results of the investigation, the JMF will become not approved. The Contractor will have to develop and submit a new JMF conforming to the requirements of C&MS 499.03.

Air Content (511.21) 

For concrete that requires QC/QA, test the air content of the concrete according to C&MS 455.03.  When QC/QA concrete is not required, the Department will test the air content as directed by the Engineer.

Concrete Requiring QC/QA

Any concrete with air results outside the requirements of Table 499.03-1 that is placed into the structure is unacceptable material according to C&MS 106.07.  The amount of unacceptable material will be the amount represented by the test result. The Contractor must re-evaluate the unacceptable material, at no cost to the Department, by coring the location containing the unacceptable concrete.  The Contractor must patch the core hole with approved material. If the concrete had high air content, the core must be tested for compressive strength.  Concrete with a minimum strength of f’c may be left in place. If the concrete had low air content, the core must be tested to determine the in-place hardened air content, specific surface and spacing factor according to ASTM C 457. The Contractor must remove and replace unacceptable materials with specific surface results less than 600 in⁻¹ (25 mm⁻¹) or spacing factor results are more than 0.008 in (0.20 mm).  The contractor must hire an independent laboratory, acceptable to the Department, to perform the testing.

Concrete Not Requiring QC/QA

Any concrete with air results outside the requirements of Table 499.03-1 that is placed into the structure is unacceptable material, according to C&MS 106.07.  The amount of unacceptable material will be the amount represented by the test result. The contractor must re-evaluate the unacceptable material, at no cost to the Department. The Department will core the location containing the unacceptable concrete. The contractor must patch the core hole with approved materials. If the concrete had high air content, the Department will test a core for compressive strength.  Concrete with a strength of f’c may be left in place. If the concrete had low air content, the Department will determine the in-place hardened air content, specific surface and spacing factor according to ASTM C 457. The contractor must remove and replace unacceptable materials with specific surface results less than 600 in⁻¹ (25 mm⁻¹) or spacing factor results of more than 0.008 in (0.20 mm).

Pay Factors (511.22)

Apply pay factors as follows:

Concrete Requiring QC/QA

The Department will use pay factors based on the percent within limits (PWL) to establish a final adjusted price.  The PWL will be established per lot(s) accepted in the QCP for each bid item quantity of concrete.  The Department will calculate a PWL according to Supplement 1127 using either the Contractor’s verified QC compressive test results or core results when the QC could not be verified.  The compressive strength pay factor (PFC) from Table 511.22-1for the lot will be applied to each bid item represented in the lot.   The Department will combine approach slab and deck concrete test results in the same lot to determine final pay factors.

If the PWL value determined for the lot of concrete is below 75%, the contractor must submit a plan for corrective action to the Engineer for approval. If the corrective plan is not approved, the Contractor must remove and replace the lot of unacceptable material, at no cost to the Department, or leave the unacceptable material in place and be paid for the lot of with a pay factor of 0.75.

Concrete Not Requiring QC/QA

For concrete items that the Department performs compression testing, the Department will use a pay factor of 1.00 based on the individual compressive strength results greater than or equal to f’c for the quantity represented by the test results.  If the compressive strength results are less than f’c, that material represented by the test result is unacceptable material, according to C&MS 106.07.See Table 511.22-2.

Method of Measurement (511.23) and Basis of Payment (511.24)

The quantity of concrete for every reference number will be determined from the plan dimensions, in place, complete, and accepted with adjustments made for necessary changes or errors.  Plan dimensions shall be verified and recorded.

The final quantity for structure concrete is rounded off to the unit for the item that is listed in the proposal.  Where plan dimensions are in inches (mm), these should be converted to feet (m) and carried to a decimal place that will not affect the accuracy of the final unit.

Calculations made for necessary changes or plan errors are to be identified properly with the structure unit and reference number and to be validated by the signature or initials of the person who made the calculations and the date they were made.

The Department will calculate separate quantities of concrete due to unacceptable compressive strength per 511.20 and air content per 511.21.

The Department will initially pay the full bid price to the Contractor upon completing the work.  The Department will calculate the final adjusted payment for each item as follows:

PF1 - The final adjusted pay per cubic yard (cubic meter) or square yard (square meter), for accepted quantities of concrete:

PF1 = (Contract Bid Price) x PFC

PF2 - The final adjusted pay per cubic yard (cubic meter) or square yard (square meter) for unacceptable quantities of concrete due to compressive strength or low air content and allowed to stay in place, according to 511.20 or 511.21.

PF2 = (Contract Bid Price) x 0.75

Calculate the adjusted price per bid item by multiplying PF1 or PF2 by the appropriate quantities of concrete, then sum the values. Subtract the full bid price paid to the Contractor from the adjusted price to determine the difference. The Department will execute final adjustments by change order upon receipt of all test data.

Documentation Requirements - 511 Concrete for Structures

Contractor has to submit an accepted Concrete Job Mix Formula (JMF) 10 days before placing concrete.

For QC/QA Concrete, the Contractor has to submit a Quality Control Plan (QCP), according to the requirements in C&MS 455.02 and 455.03.

For Mass Concrete, the Contractor has to submit a Thermal Control Plan (TCP), according to the requirements in C&MS 511.04.A.

The TCP shall include:

1.        Duration and method of curing.

2.        Procedures and equipment to control concrete temperature and differentials.

3.        Temperature sensor types, locations, installation details, monitoring system, operation plan, and a remedial action plan.

4.        Criteria for form removal to control the maximum temperature differential.

The Contractor must provide and maintain a Concrete Cylinder Curing Box.

Prior to concrete placement:

1.        Engineer received advance notice from contractor placing concrete

2.        Form dimensions and elevations field verified.

3.        Forms clean and oiled.

4.        Re-steel placed according to 509.04. 

5.        Contractor has proper equipment for placement, vibration, finishing and curing.

6.        If QC/QA concrete, the Contractor has QC staff to sample and test concrete.

7.        Forms and reinforcing steel heated to minimum 32 ºF (0 ºC) prior to placing concrete             

8.        For deck, depth, and finishing machine operation documented on Dry Run Form (Use CA-S-22 as template)

9.        Place superstructure concrete when air temperature is 85 ºF (29 ºC) or less and not predicted to be above 85 ºF (29 ºC) during placement.

10.     Prepour meeting forms CA-S-4 and CA-S-6. 

During and after concrete placement:

1.         Placement and testing requirements documented on forms CA-C-1 and TE-45.

2.        Record surface temperature inside of cold weather protection.

3.        Evaporation rate as per 511.07.

4.        Concrete vibrated.

5.        On deck, document depth obtained after final screed strike-off on day of pour.

6.        Finish deck as per 511.16.

7.        Amount of curing compound used and/or method of curing per 511.14.

8.        Loading, and removing falsework as per 511.14.

9.         Document the sawing of longitudinal grooves on deck surface as per 511.17.

10.     All joints and cracks sealed per 511.19.

11.     Smoothness requirements are outlined in 451.12 and Proposal Note 555.  A profilometer will be required to check smoothness.

12.     Placement tolerances met per 511.07 or 511.08.

13.     Compressive strength of samples met requirements per 511.20.

14.     Air content requirements met per 511.21.

15.     Pay factors calculated per 511.22.

512 Treating Concrete

Description (512.01)

This item deals with a variety of concrete treatments, including concrete surface sealing, horizontal crack sealing, vertical crack sealing, and waterproofing.

Materials (512.02)

For sealing of concrete surfaces, the Contractor must use products from the Qualified Product List (QPL) listed on the Office of Materials Management’s (OMM) website for Epoxy-Urethane sealers per C&MS 705.23A and Non-Epoxy sealers per 705.23B.

For sealing concrete bridge decks, the Contractor must use products on the QPL for High Molecular Weight Methacrylate (HMWM) Resin per 705.15, for Soluble Reactive Silicate (SRS) per 705.24, and Gravity Fed Resin per 705.25.

For sealing concrete cracks, the Contractor must use products on the QPL for Epoxy Injection per 705.26.

For waterproofing concrete surfaces, the Contractor must use products on the QPL for fabric and membrane material per the applicable sections of 711 and for asphalt primers and sealers from the applicable sections of 702 and 705.

Sealing of Concrete Surfaces (512.03)

Equipment (512.03.A)

The Contractor must follow the manufacturers’ recommendation for applying the sealer. Although spraying methods allow for higher production rates and cover profiled surfaces more easily than rollers, over –spraying must be contained and respirators and personal protection will be required. The sealer is commonly applied with rollers. When using rollers, brushes may also be required to apply the sealer to bug holes and joints.  The equipment must be clean, free of contaminants, oil, and water.

Mixing (512.03.B)

The Contractor must mix the sealer according to the manufacturer’s recommended procedures. Mixing paddles must be jiffy type, not wire whips. The mixer should be run at 400 to 600 rpm and be able to efficiently move the material for blending and not incorporate air into the mix. Material should be mixed to a consistent color for not less than three minutes.

Materials cannot be extended or thinned. Improper mixing may cause poor or no hardening and inconsistent color. Induction or rest periods impact the materials viscosity and pot life. Do not use material beyond its pot life.

Figure 512.A – Poorly Mixed Material       

Figure 512.B – Remnants of Material Applied Beyond Pot Life

Storage (512.03.C)

The sealer needs to be stored in a location where the temperature stays within the manufacturer’s recommended range. It should not be stored in direct sun light or allowed to freeze. A thermometer should be provided by the Contractor. Do not use material beyond its shelf life.

Surface Condition (512.03.E)

Improper surface preparation is one of the main reason we see sealer failures.  When the sealer is applied to a damp, dusty, or laitance laden surface, the sealer cannot gain the proper adhesion and will peel off, normally in sheets.

Figure 512.C – Sealers not Properly Bonded

All surfaces must be cleaned of dust, dirt, oil, grease, wax, curing compounds, efflorescence, laitance, coatings, and other foreign materials. All unsound areas should be repaired prior to surface profiling. Patched areas should air dry for ten days prior to sealer application. All concrete should attain its 28 day strength prior to sealer application.  Do not apply sealer to joint sealants that have not cured to the manufacturers’ instructions. Check for dust contamination prior to applying the sealer.

Surface Preparation (512.03.F)

The purposes of surface preparation are to remove dust, dirt, oil, grease, wax, curing compounds, efflorescence, laitance, coatings and other foreign materials from the concrete surface and to leave the concrete with an open, absorptive surface, exposing the sand matrix of the concrete. The concrete surface which is to be sealed should look and feel like 100 grit sandpaper or coarser (surface profile). An inadequate surface profile will not provide the anchor pattern needed for proper bonding. The Contractor is required to supply 100 grit sandpaper for comparison.

If the concrete surface had curing compound applied, the surface must be acid tested after blasting to check if the curing compound was completely removed. Perform the acid test for every 500 square feet.

1.        Use a solution of one part 20 degrees  Baume muriatic acid and two parts water.

2.        Apply four to five drops to the concrete surface. (If foaming/fizzing occurs, the curing compound was removed).

3.        If foaming/fizzing does not occur, use products approved by the sealer manufacturer to remove the curing compound.

4.        Rinse the tested location with an ammonia solution to neutralize the concrete surface.

The manufacturers of the sealer materials recommend the complete removal of existing coatings from the concrete in order for their sealer to adhere to the concrete.

There is now a separate pay item for the removal of existing coatings.

Figure 512.D – Right Side of Barrier Properly Prepared  

Figure 512.E – Barrier after Surface Preparation

Surface preparation of concrete surfaces can be done by water, abrasive blasting, or a combination of both. 

Water blast at a 7,000 psi minimum. The blasting equipment should have a gauge to verify the pressure.

Abrasive blasting needs to be followed by air brooming or power sweeping to remove dust and abrasive from the surface of the opened pores.

Ensure all wastes from the surface preparation operation are managed in accordance with C&MS 107.19. The Contractor must control fugitive dust and waste water. They must contain, collect, and properly dispose of all wastes.

Figure 512.F – Containment for Blasting Debris Waste

Make sure the Contractor is standing a reasonable distance away from the surface being blasted, typically 18 inches.  Using a 7,000 psi water blast from 6 feet away does not gain the level of cleanliness needed to correctly apply the sealer.

Figure 512.G – Combination Water/Abrasive Blaster

Figure 512.H – Abrasive Blaster

Application and Coverage (512.03.G)

If using water blasting methods, the Contractor must apply the sealer between 12 and 48 hours after surface preparation.

If using abrasive blasting methods, the Contractor must apply the sealer within 48 hours after surface preparation.

There must be no rain within 6 hours of sealer application. The ambient temperature must be above 50 ºF within 6 hours of sealer application. Time between coats shall meet manufacturer’s written recommendations. Sealer must be applied at the approved coverage rate in a continuous, unbroken film.

Epoxy-Urethane Sealers (512.03.G.1)

Epoxy-Urethane sealers must be applied at the approved application rates listed on the Qualified Product List (QPL) listed on the Office of Materials Management’s (OMM) website.  Application rate for Epoxy is 120 square feet per gallon (150 square feet per gallon if authorized), for Urethane, it is 200 square feet per gallon. Application rates for sealers will vary for form liner surfaces. Application areas should be marked to confirm coverage rates.

For sealed sidewalks, or other non-skid horizontal surfaces, sand is broadcast and the sealer backrolled to encapsulate the sand.

Sags, runs, drips, holidays, and discolorations are not acceptable.

Non-epoxy sealers (512.03.G.2)

Non-Epoxy sealers must be applied at the manufacturer’s recommended mode of application. Do not apply non-epoxy sealer if the ambient temperature is below 40 ºF or will fall below 32 ºF within 12 hours after application. Application rate for Non-Epoxy is 100 square feet per gallon for decks and sidewalks, 125 square feet per gallon on vertical surfaces, and 150 square feet per gallon on parapets, abutments, pier caps and median dividers.

These sealers are clear by nature, but are to be tinted with a vanishing dye; therefore, it will be difficult to see where progress ended on the preceding day.  Establish a method to mark the stop point that will not permanently be visible in the completed work.

Test Site/Application (512.03.H)

Ensure that test sites include a variety of surfaces:  horizontal, vertical, inverted, steel formed finish, troweled, floated, rubbed, etc.

Sealing Concrete Bridge Decks with HMWM Resin (512.04)

HMWM stands for High Molecular Weight Methacrylate. 

If the Contractor supplies 3-part HWWM, which means the promoter, resin, and initiator are supplied separately, be aware that the promoter and initiator will react violently with each other.  This chemical reaction is so violent that these components normally arrive to the job site on different trucks.  

Poor surface cleanliness is a major problem encountered in the field.  Dust and debris clog up the cracks and do not allow the HMWM to penetrate effectively.  The temperatures of the concrete surface to be treated must be the range from 50 ºF to 120 ºF. Do not apply the HMWM resin within 24 hours after rain or when rain is forecast within 12 hours of application. The application rate should be approximately 100 square feet per gallon.

Be sure to insist that the Contractor coordinate his initial application on the project with the presence of a manufacturer’s representative.  This representative should be a technical representative in lieu of a sales representative.

The application of sand is required to give the sealed surface a rough texture to assist with traction.  If the sand is applied after the resin begins to harden, it will not become embedded and will merely brush off with the first wave of traffic leaving a potentially slick surface.

Traffic should not be permitted on the treated deck until it is tack free for a minimum of 6 hours.

There is a Qualified Product List (QPL) for this material which is maintained by the Office of Materials Management (OMM) located under 705.15.

Soluble Reactive Silicate (SRS) Concrete Treatment (512.05)

Proper surface preparation is essential for SRS to perform properly.  The manufacturer’s representative must be on-site and sign off that the surface preparation is adequate.

The Contractor is required to perform a test section(s).  This section(s) should incorporate all of the surface types to be treated, since test sections are to confirm application rates and appearance which will depend on the orientation and porosity of the concrete.

The temperature of the concrete surface to be treated must be above 35 ºF.

After the treatment has cured, and prior to opening to traffic, the treated surfaces that experience vehicular or pedestrian traffic should be washed down with water.  In some instances, the SRS treated surfaces have become very slick when first exposed to water.  It is better to have this initial exposure in a controlled scenario versus allowing the first water exposure to the surface, such as rain, occur with traffic running on it. 

There is a Qualified Product List (QPL) for this material which is maintained by the Office of Materials Management (OMM) located under 705.24.

Treating Concrete Bridge Decks with Gravity-Fed Resin (512.06)

Proper surface preparation is essential for Gravity Fed Resin to perform properly. Remove all dirt and debris and all traces of asphalt or petroleum products from the deck to be treated.

The temperatures of the concrete surface to be treated must be the range from 40 ºF to 100 ºF. Do not apply the Gravity Fed resin within 24 hours after rain or when rain is forecast within 12 hours of application. The application rate should be approximately 100 to 150 square feet per gallon.

Broadcast sand over the sealed areas of the bridge deck by mechanical means.

Traffic should not be permitted on the treated deck until it is tack free for a minimum of 6 hours.

There is a Qualified Product List (QPL) for this material which is maintained by the Office of Materials Management (OMM) located under 705.25.

Sealing Cracks by Epoxy Injection (512.07)

Epoxy Injection is a process to repair cracks or fractures in reinforced concrete that are 2 to 100 miles wide. Make sure the requirement for the presence of the manufacturer’s representative is enforced even if the Contractor has vast experience with this feature of work. 

Note: The Contractor may refer to the injection ports as “straws.”

The Contractor must establish injection procedures and the depths and spacing of holes at injection ports or tees. The Contractor must remove the injection ports or tees flush with the concrete surface after the fracture has been filled and the epoxy has cured. Take core samples as soon as the epoxy has cured.  This is more critical on large jobs as the method of epoxy injection may have to be altered if it is not achieving adequate penetration.  On small, one-day type jobs, this will not be possible. 

There is a Qualified Product List (QPL) for this material which is maintained by the Office of Materials Management (OMM) located under 705.26.

Waterproofing (512.08)

Waterproofing material is applied on vertical and horizontal concrete surfaces. The waterproofing needs to be applied carefully to adhere to the concrete surfaces. Care should be taken while placing backfill or paving against and over areas that have received waterproofing.  The waterproofing can be damaged by either direct contact of the equipment or by use of backfill materials which contain large sharp edged rocks. Do not apply waterproofing fabric or membranes over attachments and hardware. Seal the discontinuities with asphalt per C&MS 702.06 or hot applied joint sealer per C&MS 705.04.

Follow the manufacturer’s recommendations for the application of prime coats, (rate of 0.10 to 0.20 gallon per square yard), prior to the application of fabric types, A, B,  or C waterproofing.  Follow the manufacturer’s recommendations for the application of the Types 2 and 3 membrane waterproofing.

If asphalt pavement is to be placed directly over the water proofing membrane, the Contractor must first apply tack coat as specified in C&MS 407 without damaging the membrane.

There are Qualified Product Lists (QPL) for the membrane and fabric materials which are maintained by the Office of Materials Management (OMM) located under 711.24, 711.25, and 711.29.

Documentation Requirements – 512 Treating Concrete

1.        General.

a.        Document type of material used (make and model).

b.        Quantity of material used and application rate.

c.        Area treated or sealed in square yards and/or lineal feet of crack repaired.

d.        Contact information for manufacturer’s representative that is on-site (where required).

e.        Atmospheric conditions and substrate temperatures.

2.        Sealing of Concrete Surfaces (512.03) (Use CA-S-21- Sealing of Concrete Surfaces Checklist Form).

a.        Copy of Superintendent’s Work Type 57 – Sealing of Concrete Surfaces certificate (class taken within last 4 years).

b.        Material Safety Data Sheet and application data from Sealer Manufacturer.

c.        Proper equipment for surface preparation (7,000 psi minimum water blaster).

d.        Concrete surface clean and free of all contaminants.

e.        100 grit sandpaper for surface preparation comparison.

f.         Containment for blasting waste water and debris.

g.        While stored, sealer not exposed to sun or frozen.

h.        Proper mixing equipment.

i.         Document atmospheric conditions and temperatures.

j.         Check application coverage and rates. Document quantity of material used.

3.        Waterproofing (512.08).

a.        All surfaces clean and dry prior to placing waterproofing.

                                                               i.      Type A, B, and D.

1.        Amount of primer used.

2.        Temperature of bituminous material.

3.        Document amount of bituminous required and amount used.

4.        Document lap of fabric.

                                                              ii.      Type 2 and 3 membrane.

1.        Temperature at time of application.

2.        Document lap of membrane.

3.        Type 3 surface joints sealed.

513 Structural Steel Members

General (513.04)

The Contractor is required to furnish the necessary access and area for inspection of all operations.  The Inspector should not occupy the same float or suspended platform used by the workmen for safety reasons.

Fabricator Documentation Responsibility (513.05)

 Fabricated steel should have a TE-24 with the shipment.  If fabricated steel arrives without a TE-24, either the District Engineer of Tests or the Office of Material Management’s structural steel section should be notified. A TE-24 in the project file provides verification that the structural steel is accepted material and fabrication has been properly performed.

Care of Material (513.10)

The Contractor is required to store structural material at the shop or in the field above the ground on platforms, skids, or other supports.

Workmanship and Straightening (513.11)

Structural steel is required to be fabricated to the dimensional tolerances specified by Section 3.5 of the AASHTO/AWS Bridge Welding Code and as specified below.

Sweep

The specified tolerance for sweep or horizontal curvature of a beam or girder is 1/8 inch (3 mm) in 10 feet (3.05 m).  This can be applied to any 10 feet (3.05 m) length of the member or multiple 10 feet (3.05 m) lengths up to the total length of the fabricated section.  A beam 100 feet (30.5 m) long, checked for its entire length, must not deviate more than ten 1/8 inches (3 mm) for a total of 1-1/4 inches (32 mm) from a taut line stretched between its ends.

Camber

The maximum camber tolerance at mid-span shall be 0 inch and the greater of + 3/4 inch or the designated haunch height.

Shipping, Storage and Erection (513.26)

Field Inspection

When the steel arrives on-site, and prior to erection, it should be inspected thoroughly for damages and for quality of fabrication as time and conditions permit. 

Damage

The nature and extent of any damage that may have occurred because of loading, transit, or unloading should be noted along with the identifying piece mark or member.  If corrective work is obvious, advise the Contractor immediately so the responsible party can be notified and correction can be performed in the most advantageous location.

Storage

Structural steel stored on-site shall be supported off the ground on blocking and stored in an upright position where it will not be affected by drainage.  Many times the Contractor will secure angle iron across the top flanges of adjacent beams to prevent them from tipping over.  If angle iron or other metal is secured across the top of the beams, it is important to ensure that the Contractor has not secured the angles or other metal by welding it to the beam.

Check of Bearing Seats

A final check shall be made of the elevation of bearing seats on the piers and abutments before erection of structural steel is scheduled to begin.   If bearing seats are found that need to be corrected, it must be performed in the manner and to the tolerances described in 511 Bearing Seats of this manual.

The findings of this final check should be filed in the project records.

Erection

Required Erection Procedures

The specifications require the Contractor to submit an erection procedure for structural steel members.  If there is railroad involvement, the PE stamped plan needs to be reviewed and approved by the appropriate railroad.  Otherwise, the plan must have two PE stamps.  For additional requirements refer to C&MS Item 501.05.

Methods and equipment submitted for erection of members must be used in handling during transportation to the bridge site and unloading.

The erection drawings, usually the “E” sheets of the accepted shop drawings, must be used to locate the members on the bridge and may give special instructions for the erector to follow.

Deviations from the submitted erection procedure are not permitted.  If the erector proposes deviations in a procedure that appears to have merit, they must re-submit their modified erection procedure per C&MS 501.05. Lack of Departmental acceptance does not supersede the Engineer’s authority per C&MS 105.04.

Typical Erection Procedures Items

Typical items that should be included in the proposed erection procedure are as follows: (Reference C&MS 501.05.B.4. use Erection Checklist Form CA-S-20).

1.        A drawing of the complete framing which shows each girder or beam section by “piece mark” and numbered in the order of proposed erection. 

2.        A print of the erection sheet of the shop drawings may be used.

3.        The number of pieces and load capacity of erection equipment to be used and method of lifting members.

4.        Field splices to be made on the ground.

5.        The number of field splice holes to be filled before erected members are released and allowed to deflect (50 percent required, preferably one-half with pins and one-half with bolts).

6.        Methods and details for supporting the first beams or girders at the abutments and piers in each unit. Where some sort of attachment to the pier is used, it should be described as to size of members and method of attaching to the pier and steel.  In addition to supporting the beams at the abutment and piers, there may also be additional bracing of the top flange at mid-span to prevent the beam from twisting or buckling under its own weight. 

Bearing Adjustment (Also refer to Item 516 Bearing Device section of this manual)

When steel beams or girders are first landed, and before sole plates are fastened, bearings may be set approximately plumb.  After all beams or girders between expansion joints are in place and the overall length has been checked, make temperature corrections in the plumbness of the bearings.  The length of bridge from the fixed bearing and the deviation in temperature of the steel from 60 °F (16 °C) must be used in calculating the tilt to the bearings when rockers are used.

The coefficient of expansion to multiply with the length and temperature difference is 0.000006 (0.0000117).  For example, for a two-span length of 160 feet (49 m) at 40 °F (4 °C) for a difference of 20 °F degrees (-7 °C), the calculation is 160 x 20 x 0.000006 = 0.0192 feet or 1/4 inch (49 x 11 x 0.0000117 = 0.0060 m or 6 mm) that the rocker should be inclined from the vertical toward the fixed bearing to compensate for the existing temperature. 

The same factors must be used to determine the offset in sliding plate bearings.

Adjustments should be made on a cloudy day when a temperature differential in the steel is not caused by the sun’s rays.

A final check of correct bearing adjustment must be made after the deck has been completed.

Elastomeric bearings cannot be adjusted for temperature as there is no way to keep them in a deformed shape.  Due to this, if it is necessary to correct for temperature due to excessive deformation or racking of the bearings, the beams will have to be jacked up and the bearings reset when the temperature is close to 60 °F.

High Strength Steel Bolts, Nuts, and Washers (513.20)

The following described operations are intended to clarify some of the important requirements of the specifications.

Joint Assembly

The beams or girders to be spliced must have their ends brought together at the correct relative elevation with respect to support points and be held at the elevation, and in correct alignment, so that heavy drifting is not necessary to align the holes.

Sufficient pins must be installed to obtain accurate alignment of parts and sufficient bolts to compact the joint.  Before the beams or girders are released and allowed to deflect, at least 50 percent of the holes must be filled with pins and snug-tightened bolts.  A minimum of 25 percent pins is desired. However, if less than 25 percent will carry the stress and if additional pins cannot improve matching of holes, a lesser number will be satisfactory.  If less than 25 percent pins are used, the remaining holes should be filled with snug-tightened bolts. Highly stressed joints will most likely require more than 50 percent of the holes to be filled with drift pins and snug-tightened bolts; note such cases on the accepted erection procedure.  Due to the possibility of damaging the threads on the bolts, any bolts installed prior to installing the drift pins shall be replaced.

On some beams and girders, it is possible for the initial bolts used to compact the joints to become loose when the remaining bolts are installed.  After all the remaining holes have been filled with bolts and tightened to at least a snug tight condition, the initial bolts should be checked to ensure that they are still snug tight. 

When the splice is made on the ground, all operations to complete the splice shall be performed.

Pins shall be cylindrical and no more than 1/32 inch (1 mm) smaller than the diameter of the hole.

All holes not filled with pins shall be filled with bolts and bolt tightening operations completed on them before removal of any pins.

Bolt Tightening

Tighten bolts by the turn-of-the-nut-method.

1.        Tighten the bolt to a snug-tight condition.

2.        Match mark the protruding end of the bolt and adjacent surface of the nut.

3.        Tighten the nut to the additional specified rotation.

Greater variation in tension is usually obtained when the snug-tight condition is performed with power wrenches.  More consistent tension is obtained with spud wrenches.  When the steel surfaces are flat and compact, the snug-tight condition is obtained when bolt tension is between 5,000 and 10,000 pounds (22,222 and 44,444 newtons).

Snug-tight is accomplished by either an impact wrench or an ordinary spud wrench.  If an impact wrench is used, snug-tight is achieved when the impact wrench begins to impact or hammer on the bolt.  This will happen almost immediately after tightening with the impact wrench.  When a spud wrench is used, snug-tight is achieved when the full effort of a man is applied to the spud wrench and the nut cannot be tightened any further.

Bolts must be match marked after the bolts have been tightened to a snug-tight condition.  The purpose of the match mark is to measure the amount of rotation of the nut relative to the bolt.  The match marks must be placed properly in order to measure this rotation.  The match marks must be placed on the end of the bolt and the adjacent surface of the nut.  Contractors have placed match marks in several other locations; however, none of these locations allow the relative rotation of the nut to the bolt to be measured

(See Figures 513.A and 513.B - Match Marked Bolts).

Figure 513.A – Match Marked Bolts

Figure 513.B – Match Marked Bolts

During final tightening, all of the specified rotation must be performed.  Although the bolts may be over-tightened in the snug-tight condition by power wrenches, the full specified rotation is still required.  A maximum tension is not specified and excessive tension is not cause for rejection.

The first complete joint on a project must be tested.  If certain conditions are met, inspection of subsequently-completed joints by testing may be waived by the Engineer.  These conditions are:

1.        The Engineer has accepted the compactness of the joint.

2.        The snug-tight operations have been witnessed and accepted by the Engineer.

3.        Match-marking of the protruding end of the bolt and nut have been performed and indicates the required rotation.  The Engineer must be satisfied that these conditions have been met completely before the joint will be considered accepted and testing waived.

4.        Galvanized A 325 (A 325 M) bolts, and bolts that were installed prior to inserting drift pins and subsequently replaced, shall not be reused.  All other A 325 (A 325 M) black (un-galvanized) bolts may be reused if accepted by the Engineer.  Re-tightening previously tightened bolts that may have been loosened by the tightening of adjacent bolts is not considered reuse.

Inspection of Bolted Joints (513.20.E)

Even though a joint may appear to have all the bolts in the joint properly match marked and tightened, there is still the possibility that these bolts were not properly tightened.  Therefore, it is necessary for the Contractor to provide a torque wrench and a recently calibrated tension testing device.

The minimum torque required must be determined prior to inspecting the bolts with the torque wrench.  This is accomplished with the aid of the tension testing device.  A bolt is first placed in the tension testing device and tightened to the required tension as given by Table 513.20-2 in the C&MS.  The torque wrench is then used to determine how much torque is required to turn the nut on the bolt after the minimum tension has been achieved.  When calibrating the torque wrench, the Engineer should hold his hand on the nut being tightened in order to detect movement or rotation of the nut on the bolt.  The required torque is based on the average torque of three bolts. 

The torque wrench should be calibrated at the beginning of each day it is used and for each diameter or length of bolt being tested.  Also, if the coating varies (i.e., galvanized bolts as opposed to un-coated bolts), the torque wrench should be calibrated.

Torque wrenches must have the capacity of the maximum job inspection torque required for any bridge.

The Contractor applying the torque should perform the inspection only up to the job inspection torque.

Calibration Devices (513.20.F)

The Erector must furnish the Engineer with evidence that the manufacturer or a laboratory has checked the tension-testing device within one year.

Welding (513.21)

Welding requirements must be according to the current ANSI/AASHTO/AWS “Bridge Welding Code,” except as modified by Supplement 1011 and the Construction and Material Specifications.

No attachments, other than specified by the plans, shall be made by welding to any main structural members such as beams, girders, cross-bracing, truss members, etc., unless accepted by the Office of Structural Engineering.

Approval of Welders

All welds must be performed by welders qualified for the specific welding method to be used according to Supplement 1011.  The Office of Material Management must approve all welders prior to any welding.  A list of qualified welders is maintained by the Office of Materials Management.  Welders must have been tested in the last 5 years.

Electrodes and Welding Procedures

Electrodes used to make all permanent welds to steel must be of the low hydrogen type and must be on the list of accepted electrodes maintained by the Office of Material Management.

In order to prevent moisture in the atmosphere from being absorbed by the electrodes, which can cause potential cracking of the weld, all stick electrodes must be purchased in a hermetically-sealed container or must be dried in an oven at 450 °F to 500 °F (232 °C to 260 °C) for 2 hours and stored in a suitable container that will maintain a temperature of no less than 250 °F (121 °C).  After removal for use, stick electrodes exposed to the atmosphere for more than 4 hours for E70XX electrodes and 2 hours for E80XX electrodes must be re-dried at a temperature of 450 °F to 500 °F (232 °C to 260 °C) before use. 

When electrodes have become wet, the coating on the electrode is altered.  Drying the electrodes does not restore the electrode coating to the original manufactured condition. Therefore, electrodes that become wet shall not be used.

The welding procedure which uses shielded metal arc electrodes (stick welding) is the only pre-accepted procedure.  If the Contractor proposes to use Flux Core Arc Welding (FCAW), Submerged Arc Welding (SAW), or Gas Metal Arc Welding (GMAW), he must first have a welding procedure qualification test accepted and then submit a welding procedure specification for approval.  Questions on welding procedure qualification tests and welding procedure specifications can be answered by the Office of Material Management’s structural steel section.

Weather Restrictions

When the base metal is below the temperature listed in Table 513.A for the thickness of the material being welded, it must be preheated in such a manner that surfaces being welded are at or above the specified minimum temperature for a distance equal to the thickness of the part being welded, but not less than 3 inches (76 mm) both laterally and in advance of the welding.

Table 513.A – Minimum Preheat Interpass Temperatures

Thickness of Thickest Part at Point of Welding     – Inches (mm)

Minimum Temperature

A709 70W

All Other Steel

To ¾ (19), incl.

50 °F (10 °C)

50 °F (10 °C)

Over ¾ to 1-½  (19 to 38), incl.

125 °F (50 °C)

70 °F (20 °C)

Over 1 ½ to 2-½ (38 63.5), incl.

175 °F (80 °C)

150 °F (65 °C)

Over 2-½  (63.5)

225 °F (110 °C)

225 °F (110 °C)

When the base metal temperature is below 32 °F (0 °C), the above specified should be preheated to minimum temperature of at least 70 °F (20 °C).  Preheating is only necessary where the welding begins. Continued welding will make further preheating unnecessary.  Welding shall not be done when the ambient temperature is below 0 °F (-18 °C).

Welding Inspection

The welding operations should be observed and complete welds inspected for conformance to the plans and shop drawings.  Fillet welds must be measured with the use of a weld gauge or other method that will show the length of the sides in contact with the steel.  Deficient welds must be built up to the required size.  Poorly shaped welds or welds containing defects such as cracks, pits, craters, and undercutting must be corrected to the satisfaction of the Engineer.

When radiographic examination of welds is required, the report and film must be submitted to the Office of Materials Management, Structural Steel section, for review and approval.  This must be done before any work is performed that would interfere with any necessary corrective work.

Arc Strikes

Occasionally during the welding operation, the electrode will come in contact with an area of steel that is not to be welded.  This contact will result in a small burnt spot or arc strike in the steel.  If not properly removed, an arc strike has the potential of propagating fatigue cracks.

Arc strikes located must be removed by grinding.  They can result in unacceptable hard spots or small cracks.  Therefore, after the arc strikes are removed, the Contractor must check every location where they occur where the steel is in tension.  The Contractor must perform a magnetic-particle test on all arc strikes to ensure that no cracks are present.  Hardness tests must be run on all locations to ensure that no unacceptable hard areas are present.  Hardness values shall not exceed the higher of Rockwell C30 or the hardness value measured in the steel outside the location of the arc strike.  If the above testing reveals unacceptable results, the flaw can be removed by grinding and the steel be retested to assure that the flaw has been completely removed.

Normally the Contractor is not equipped nor has the knowledge to perform the above test.  He will typically make arrangements for a private testing laboratory to perform the required testing.

Cleaning Of Welds

The finished weld must have all slag removed and be neutralized by vigorous wire brushing to remove any film that will affect the proper adherence of paint.

Stud Shear Connectors (513.22)

Shear studs are short rods that have been welded to a piece of steel for the purpose of anchoring that steel to concrete.  There are additional requirements to inspect the weld joining the shear stud to a piece of steel.

Qualified Stud Welder Operator

Prior to allowing any production welding, it is first necessary to ensure that the stud welder operator is qualified.  This is accomplished at the project site since there is no list of qualified stud weld operators.

To be qualified, one must successfully weld two studs of the same type and size that will be used during the production welding.  The studs must be welded to a piece of steel that is similar to the production member in thickness and property or they may be welded to the production member.

The studs should be visually examined after they have been welded.  If they were welded properly there should be weld metal completely around the base of the stud (360 degree flash).

In addition to a visual examination, the studs must be bent to an angle of approximately 30 degrees from their original axis.  Bend the studs by either striking them with a hammer or bending the stud by use of a pipe.

If the visual examination does not reveal a 360 degree flash or if the weld fails when the studs are bent over, the Contractor must make corrections to his procedure and two more studs must be welded and tested.  This should continue until two consecutive studs are tested and found to be satisfactory.

Qualifying the Stud Welding Procedure

Prior to production welding, it is necessary to qualify the stud welding procedure.  This should be performed at the beginning of each day’s shift when welding has been interrupted for an hour or more, when attaching the welding cable to a different ground, when changing weld settings, when changing loops in the cable, or when 500 studs have been welded after testing.

The actual testing shall be the same as required for qualifying the stud welding operator.

Post Testing of Stud Welds

After the studs have been welded, it is necessary to test the studs to ensure that they have been installed correctly.  Test the studs by giving each one a light blow with a hammer.  When the studs are tapped, they should emit a ringing sound.  Any stud that does not emit a ringing sound should be bent approximately 15 degrees from its original axis.

In addition to tapping the studs with a hammer, a visual inspection must be performed.  Any stud that does not show a 360 degree flash may be repaired by the Contractor by fillet welding the missing flash.  Any stud the Contractor elects not to repair, or any stud that the Contractor has not repaired properly, must be bent to an angle of approximately 15 degrees from its original axis. 

Any stud that does not pass the bend test must be replaced.  All studs that have been bent and have not failed should not be straightened.

Shop Coatings (513.27)

Any members where thickness appears questionable from a visual examination shall be checked in the field, preferably prior to erection.

Documentation Requirements - 513 Structural Steel Members

1.        Check fabrication for compliance.

a.        Pay in accordance with pay weight as accepted from the Office of Material Management or on a lump sum basis.

b.        TE-24 on file for Structural Members.

c.        Shop Drawings per C&MS 501.04.

2.        Bearing Seat Inspection.

3.        Document condition of beams/girders on delivery.

a.        Damage.

b.        Sweep.

c.        Camber.

d.        Shop Coating.

4.        Beams/girders set according to erection procedure per C&MS 501.05. Use Erection Checklist Form CA-S-20.

5.        Bolted Splices.

a.        Ensure Contractor's compliance with approved erection procedure.

b.        50 percent of holes filled with drift pins and snug-tight bolts (25 percent for each).

c.        Furnish calibration of torque wrenches and skidmore device.

d.        Document that Engineer inspected first completed joint and others as necessary.

e.        Check no fewer than 10 percent of tightened bolts.

6.        Welding.

a.        Welding rods stored in a warm, dry area.

b.        Inspected for size.

c.        Document type of welding (stick welding is pre-qualified; all others require Central Office approval).

d.        Verify and document welder’s qualifications with approved welders list maintained by the Office of Materials Management.

514 Painting of Structural Steel

Description (514.01)

In order to protect structural steel from corroding, it is necessary to apply a protective coating system.  The coating system consists of three coats.  On existing steel, all three coats are applied in the field.  On new steel, inorganic zinc primer is normally applied in the fabrication shop and the remaining two coats are applied in the field.

Quality Control (514.04)

Quality Control Specialist (514.04.A)

When applying coating systems, it is very important for the Contractor to constantly monitor the quality of the work.  Due to his many duties and responsibilities, the foreman is not able to properly monitor the quality of the work.  Therefore, the Contractor is required to assign one person the duties of a Quality Control Specialist (QCS). If there is no QCS on the project, the Contractor is not allowed to proceed with any production work.

This person must be formally trained as a QCS. Prior to allowing the QCS to begin work, the Engineer should confirm that the QCS appears on the approved list maintained by the Office of Construction Administration (OCA).  This list can be viewed on their website.

The QCS is only to be involved in quality control work while production work is going on. He is not to be a foreman or a member of the Contractor’s production staff.  He is not allowed to abrasive blast, apply coating, recover spent abrasive, mix paint, run errands, set up or maintain the traffic control, run or work on the equipment, etc.  It is imperative that the QCS does not perform supervisory duties on the production staff.  If the QCS is not performing his duties or is involved in any work other than quality control while production work is proceeding, the violation should be documented and remedied.  It should then be determined, based on the disqualification guidelines in the specification, if the violation(s) warrants disqualification of the QCS.  If the project staff feels that the criteria for disqualification have been met, all documentation of the violation(s) is then sent to the Office of Construction Administration for review.  The QCS should be allowed to continue work during this review process.  If the Office of Construction Administration determines violations are substantiated, the QCS will be permanently disqualified from their duties as the QCS.  The Office of Construction Administration will inform the project staff of the disqualification and the QCS should then be relieved of his duties as the QCS.

The Quality Control Specialist must be properly equipped with all the necessary testing equipment and be able to climb to all parts of the structural steel. He has the authority to stop the Contractor’s work if necessary and to inform the foreman of all work that does not meet the requirement of the specifications.

Quality Control Points (QCP) (514.04.B)

The purpose of the quality control points is to mandate points in the surface preparation and painting process where the work can be inspected to ensure compliance with the specifications.  It is important that the QCS signs off at all QCPs to verify that the work being inspected has been checked and is in complete compliance with the specifications.  This sign-off puts the accountability for quality on the QCS.  Only after receiving the QCS sign-off should the formal joint inspection begin.  The Contractor’s Quality Control Specialist (QCS) and the owners’ Inspector (QA) must make independent checks and document the work at the Quality Control Points.

Testing Equipment (514.05)

The testing equipment listed in the specification must always be available for use by the Inspector.  If the equipment is not available or not in good working order, all production work should be halted.  Electric equipment must have batteries and bulbs to be considered in good working order.  The tables and visual standards must be legible.  There must also be film or photographic printing equipment available. 

The list in the specification indicates the testing equipment that must be supplied by the Contractor, but it in no way limits the means by which the Inspector may inspect the work.  This may include, but is not limited to, mirrors and larger lights.  Note: Magnification is not allowed to be used for the determination of SSPC-SP10 blast condition.

Work Limitations (514.06)

Abrasive blasting and painting is to be done between April 1 and October 31.  The Contractor should plan his work to ensure that he is at an acceptable stopping point on October 31.  This date is not to be waived without concurrence from the Office of Construction Administration.

Temperature (514.06.A)

Paint, except for inorganic zinc, must be applied when the temperature of the air within the enclosure, steel surface, or paint is 50 °F (10 °C) or higher and is expected to remain above 50 °F (10 °C) for the times noted in the table shown in 514.06.A.  It should be noted that the times shown in the table are not recoat times.  They simply dictate the required time a particular temperature must be maintained after the coating is applied.  At lower temperatures the paint will not cure, and in some cases, the paint may not resume curing when the temperatures warm up.  It is important to pay close attention to the temperature in the early spring and the late fall.  During the early spring and the late fall, the temperatures will be above 50 °F (10 °C) during the day, but the temperature will drop during the early evening hours before the paint has had enough time to properly cure.

The surface temperature of the steel should be taken in the area that is the coldest.  This is not always the same on every structure (i.e., the fascia beam bottom flange).  If you cannot tell where the coldest area is by running your hand over the steel, then it may be necessary to take readings in multiple areas.

For inorganic zinc, apply when the air, steel surface, and paint is 40 °F (4 °C) or higher.

Paint must be applied when the temperature of the steel is at least 5 °F (3 °C) above the dew point.  Applying paint to steel at temperatures below 5 °F (3 °C) above the dew point could result in condensation on the surface of the steel.  The dew point is to be determined by using the psychrometer and the psychrometric tables or comparable electronic or digital equipment for the measurement of dew point, accurate within 2 ºF and within one percent relative humidity.  The psychrometer should be used in the area to be painted or blasted (i.e., in containment near the beams).  Note: If the barometric pressure is unknown when using the psychrometric tables, it is acceptable to assume a barometric pressure equal to 30 inches. 

Abrasive blasting must be performed when the steel is at least 5 °F (3 °C) above the dew point.  This is due to the possibility of condensation.  The Contractor will be required to re-blast the steel if this requirement is not met.

Heated enclosures may be used to maintain the temperatures above the minimum specified temperatures.  If combustion type heating units are used, the exhaust fumes must not be permitted in the enclosure, but should be vented away from the enclosure. If exhaust fumes are not properly vented, they can leave a deposit on the surface that could affect the ability of remaining coats of paint to properly bond to the steel or the previous coats of paint. These exhaust deposits could contaminate the freshly applied paint.

A recording thermometer should be used to ensure that the minimum temperature is maintained until the coating has cured.  The thermometer should be placed close to the perimeter of the enclosure since this is the area subject to cooler temperatures.  The paper graph generated by the recording thermometer should be copied and filed as part of the QCP documentation.

Pollution Control (514.08)

Special note should be made to address the handling storage and disposal of hazardous materials used during construction.  Handling, storage, and disposal of any volatile products are of particular concern.  These would normally include thinners, reducers, and solvents.  Common types of volatile used in a painting operation may include methyl ethyl ketone (MEK), xylene, and toluene based materials.

When these types of items are on-site, it is important that the Contractor (1) submit MSDS sheets for each product, (2) maintain a current inventory sheet as to the quantity of each product (3) properly label usable product and hazardous waste created by the use of these products, (4) properly containerize and store these products and wastes so as to not create a health and safety hazard or exposure to the environment, and (5) waste containers must be managed in such a way that hazardous waste and non-hazardous waste are properly stored and kept separate.

Inspection Access and Lighting (514.10)

Proper inspection cannot be accomplished unless the Inspector has access and proper lighting to see every surface to be painted. 

To accomplish this, the Contractor is required to provide, erect, and move scaffolding and all other equipment necessary to provide the Inspector access to closely inspect the work.  On bridges with tall girders, placing scaffolding only under the girders is not adequate to provide proper access to the work. The Inspector should not climb around on the structural steel to inspect the work.  If the Contractor fails to provide proper access to inspect the work, he should not be allowed to continue since proper inspection cannot be performed.

All scaffolding of any width, whether it is supported by a wire rope, mounted on the back of a truck, or supported by any other means, that is at least 21 inches (533 mm) or more below the surface to be painted, must have guard rail placed on all sides.  It is not necessary for scaffolding that is less than 21 inches (533 mm) below the surface to be painted to have guardrail on the two sides bounded by the structural steel, but in this case, the scaffolding must be at least 28 inches (711 mm) wide.

One row of guardrail is required to be placed around the scaffolding when it is at least 21 inches (533 mm), but less than 43 inches (1092 mm) below the surface to be painted.  Two rows of guardrail are required when the scaffolding is placed 43 inches (1092 mm) or more below the surface to be painted.

Remember you should never utilize a means of inspection access that you do not foresee as being safe.

Job Site Visual Standards (514.11)

Prior to production blasting, it is imperative that a test section be blasted and the job site visual standards be agreed upon and documented.  A comparison to these standards will be utilized for the rest of the project to accept the surface preparation of the steel.  The test section allows the Contractor to adjust his grit size/blast pressure combination to maximize his production while producing work that is within the specifications. 

Note: In the event of a dispute, SSPC-VIS 1 will govern.

Quality Control Point Photographic Verification and Documentation (514.12)

Document the work with photographs, especially at Quality Control Points 3, 4, and 11.

Surface Preparation (514.13)

One of the most important items of work is surface preparation.  It is the most labor intensive and expensive phase of the work. 

Solvent Cleaning (QCP #1) (514.13.A)

Prior to abrasive blasting, areas that contain asphalt cement, oil, grease,  diesel fuel deposits, or other petroleum products and contaminants must be solvent cleaned.  It is not necessary for the Contractor to solvent clean the entire surface of the steel to be coated, but only those areas that contain these contaminants. 

Solvent cleaning per SSPC-SP1 requires the removal of foreign material  prior to solvent cleaning.  This can be done by one or a combination of the following: wire brushes, abrade, scrape, or clean with solutions of appropriate cleaners followed by a fresh water rinse.

Make sure that all solvent brought on-site are accompanied by a current MSDS for that product.

All solvent cleaning should be completed prior to the start of the abrasive blasting operation.  If this is not accomplished, the abrasive blasting operation will not remove the asphalt cement, oil, grease, diesel fuel deposits or other petroleum products and contaminants but drive them into the steel.

In order to remove all residual solvent, asphalt cement, oil, grease, or diesel fuel deposits after the solvent cleaning, all solvent-cleaned areas are to be washed with water at a pressure of at least 1,000 psi (7 Mpa).  In order to be effective, the nozzle must be held no further than 12 inches (300 mm) from the surface being washed.

Grinding Flange Edges (QCP #2) (514.13.B)

The specification requires that bottom flange edges of all beams are to be rounded to a radius of 1/8 ± 1/16 inch.  This includes both rolled beams and girders.  It is impossible for an edge to be given a radius with one straight pass of a grinder.  It requires multiple straight passes or a rounding motion.

The radius is necessary to allow the application of the proper coating thickness.  The sharp edge splits the spray of paint which results in only a thin coating of paint being deposited along that edge.

Abrasive Blasting (QCP #3) (514.13.C)

The prime coat contains zinc that protects the steel by reacting chemically with the surface of the steel.  It is important to remove all foreign material from the surface of the steel to allow the zinc particles to come in contact with the bare steel.  It is also important to roughen up or produce a profile on the surface of the steel.  The profile aids the coating in adhering to the surface of the steel.

Steel surfaces to be painted are to be abrasively blasted to a near white metal, SSPC-SP10.  SSPC-SP10 is generically defined as white metal with an allowable 5 percent staining.  This allowable staining is a discoloration.  It does not have any volume or noticeable thickness.  It should be noted that SSPC-SP10 does not allow magnification for this determination.  During inspection, pay special attention to areas that are more difficult to blast or areas that might be difficult to inspect.  These areas include under cross-frames, around bolt heads and nuts, end dams, cross-frames next to or close to back walls, and any other areas of limited access.  After the steel is blasted, it must be maintained in that condition until it is painted.  The backside of cross-frame assemblies that are 3 inches (75 mm) or closer to backwalls may be commercial blast cleaned according to SSPC-SP6.  SSPC-SP6 in generically defined as white metal with an allowable 33 percent staining.  Again, this staining does not have any noticeable thickness.  It is not a residue or film. 

The abrasive used in the field must be steel grit or a recyclable natural mineral, low dusting abrasive. Do not use silica sands, mineral slags, and other types of non-metallic abrasives that contain more than 0.5 percent free silica by weight, have a chloride content more than 25 ppm, and contain any organic material. The Contractor needs to supply material data sheets proofing that the mineral meets these requirements.  The abrasive must be recycled to minimize the volume of waste material placed into landfills.  The size or gradation of the grit is not specified, but must provide a profile of 1.5 mils to 3.5 mils.  G40 and G50 size steel grits are commonly used by contractors for abrasive blasting in the field.  The profile should be continuously monitored during the blasting operation since the size of the abrasive can be reduced due to being recycled, which can in turn reduce the size of the profile.  The size of the profile can also be reduced if the air pressure at the blasting nozzle is reduced.  The profile should be monitored by the use of extra-course replica tape and a spring micrometer.  Make sure the replica tape is extra-course as this is the appropriate tape to measure our specified profile range of 1.5 mils to 3.5 mils.  It is necessary to account for the 2.0 mil adjustment required for the thickness of the replica tape.  This adjustment can be subtracted from every reading or the micrometer can be zeroed to -2.0 mils which results in a direct reading being taken from the micrometer.

Some abrasives, when received by the Contractor, can be contaminated with oil.  Abrasives should be checked to ensure that they are free of oil.  This check should be made by placing a small amount of abrasives in a jar with tap water.  The abrasives and water should then be stirred or shook up.  The top of the water should then be checked for signs of oil.  If oil is detected, the abrasives should not be used.

Apply a prime coat to the steel that is blast cleaned in the field within 12 hours of the beginning of abrasive blasting.  This requires that the time and location the blasting was started is accurately documented.  This requirement is extended to 24 hours for shop blasted steel as it is a more controlled environment. 

After abrasive blasting is complete, all abrasive and dust must be removed from the surface to be painted.  Dust and abrasive must be removed from any adjacent painted surface or any adjacent structure.  Dust and abrasive should be removed as soon as possible to prevent rust staining of adjacent surfaces. Rust stains can be very difficult to remove.

Occasionally the compressed air used to propel the abrasive can become contaminated with oil or water from the compressor.  This oil or water, if deposited on the surface of the steel to be painted, can be detrimental to the coating system.  To prevent this problem, the Quality Control Specialist must blow air from a nozzle for 30 seconds onto a white cloth or blotter held in a rigid frame.  This testing must be done at the start of each shift and at 4 hour intervals.  If any oil, water, or other contaminates are present on the cloth or blotter, the blasting operation must be suspended until the problem is corrected.  After the operation is corrected, and before the blasting operation is permitted to proceed, another test should be made to ensure that the problem has been corrected.

Containment/Waste Disposal (QCP #4) (514.13.D)

The Contractor must comply with all federal, state, and local laws, rules, regulations, and ordinances.

Due to the possibility of the existing coating containing lead , chromium, cadmium, or arsenic, which are considered hazardous substances over regulatory concentrations, the Contractor is required to erect an enclosure to completely surround the area where the existing coating will be removed.  Not only should the enclosure be placed vertically around the sides of the blasting operation, it should be placed on the ground under the blasting operation. In addition to containing potentially hazardous debris, the enclosure prevents fugitive dust from escaping into the environment. 

The enclosure must be constructed of materials that are free of tears, cuts, or holes to prevent dust and lead from escaping into the environment.  Holes, cuts, or tears that do occur should be repaired immediately.  The perimeter of the enclosure should extend up between the beams to the bottom of the concrete deck.  All seams should be fastened or lapped in a manner that ensures a seal and does not allow any openings between the screens or materials of the enclosure. The area where workers enter and exit the enclosure should be sealed.

In addition to placing an enclosure around the blasting operations, the Contractor must place ground covers under all equipment.  This ground cover must be placed under the equipment for its entire length, not just a portion of its length.  If the ground is not properly covered, there is the possibility that it could become contaminated.  These ground covers are intended to reduce the impact of equipment leaking oil, fuel, or hydraulic fluid.

All abrasive blasting debris is to be picked up at the end of the day and must be stored in steel containers that have lids which lock.  The Contractor will store the debris in 55 gallon drums with lids.  The lids have a ring around them that are capable of being locked.  Normally, the Contractor will lock the lids by means of a bolt.  This method is acceptable as long as there is a nut placed on the bolt and tightened by the use of a wrench. Many times the lids are not properly locked at the end of the day.  They should be checked at the end of the day or the first thing in the morning to ensure that the Contractor is properly locking the lids.  The use of tie wire, zip ties, or duct tape are not acceptable as a means for locking the lids.  If the Contractor chooses to use a large roll-off container to store abrasive blasting debris, the requirement for providing a means to lock the lid of the container must still be enforced.

Within the first week of production blasting, the Contractor must sample the abrasive blasting debris and have it sent out for testing.  If the samples come back with lead, chromium, cadmium, or arsenic contents higher than the limits shown in the table in Section 514.13.D.1 of the Construction and Material Specifications, the abrasive blasting debris is considered hazardous.  Note that parts per million for these items is equivalent to mg/L.  The Contractor must dispose of the abrasive blasting debris within 60 days after it is generated.  The 60 days starts as soon as the Contractor generates the debris, not after the completion of the abrasive blasting operation.  If the debris remains on the project site over 90 days, the state and the Contractor could be cited by the Environmental Protection Agency.  On smaller structures, the debris can be removed in one operation.  On larger structures where the abrasive blasting operation extends over a period of several months, it will be necessary to make several trips in order to comply with the 60 day limit.  If after 60 days, the Contractor has not properly disposed of the debris, all abrasive blasting and painting of the structural steel on the project must immediately cease until the waste is properly disposed.  At this time, the Department must cease processing all pay estimates and send notification to the Contractor’s surety that he has breached the Contract.

Handling (514.15)

Note that the date of manufacture does not show up on all container labels.  Some manufacturers show a code number in lieu of a date of manufacture.  You will need to call the manufacturer and give them this code number and they will in turn give you the date of manufacture.

Mixing and Thinning (514.16)

Prior to applying paint, it is necessary to thoroughly mix all the ingredients together.  This is to be accomplished with a high shear mixer.  Paddle mixers are not allowed since they will not adequately mix the different ingredients together.  Do not use compressed air to cause a stream of bubbles in the paint and paint shakers since it will not properly mix the ingredients.

During the application of the primer, it is important that it be continuously mixed. If it is not continuously mixed, the zinc particles in the primer will settle to the bottom of the container and will not be applied to the structural steel.  To ensure that the mixing process is not interrupted, it is important that the mixer be an automated mixer, not a hand held mixer.

Thinning of the paint is typically not required.  However, if the Contractor elects to thin the paint, it is important that it be thinned with the correct type and volume of thinner.  To ensure that the Contractor is using the proper type of thinner, only use thinner recommended and supplied by the paint manufacturer.  The maximum rate of thinner is to be as per the manufacturer’s printed instructions.  If the paint manufacturer’s printed instructions do not list a maximum proportion of thinner, the manufacturer should be contacted to obtain their recommendation.  Note: The manufacturer may recommend different thinners based on humidity or temperature.  All thinning should be done in the presence of the Engineer or Inspector. 

In an effort to ensure that the thinner the Contractor is using is the thinner recommended and supplied by the manufacturer, only use thinner that has been supplied to the project in unopened containers with the labels intact.  The amount of thinner used from each container should be monitored to prevent refilling of the container with other types of thinner.

The above restrictions do not apply to the thinners that the Contractor uses to clean his equipment.  Be aware that methyl ethyl ketone (MEK) is sometimes used as both a reducer and a cleaner.

Coating Application (514.17)

Paint is applied to provide the specified coating thickness by the use of brush or spray methods.  Rollers can cause bubbling and other irregularities in the coating. Use daubers, small diameter rollers, or sheepskins to paint the following areas of difficult access: (1) where cross-frame angles are located within 2 inches (50 mm) of the bottom flanges, (2) where end cross-frames are within 6 inches (150 mm) of the backwall, (3) where there is less than 6 inches (150 mm) between the bottom of the bottom flange and the beam seat, and (4) other areas as determined by the Engineer.

Application Approval (513.17.B)

The specification states that each spray operator shall demonstrate to the Engineer or Inspector the ability to apply the paint as specified.  This allows the project staff to remove a painter that is unable or unwilling to produce work within the specification requirements.

Surface Cleanliness (513.17.D)

All surfaces to be painted shall be free of dust, dirt, and moisture.  If these or other contaminants are left on the surface they can cause multiple types of defects, including adhesion failures and accelerated rusting.  Simply blowing down with compressed air is not always sufficient.  It is sometimes necessary to wipe the surface down, use a vacuum system, or some other means to adequately prepare the surface to receive paint.  This cleanliness requirement includes both the blasted steel surface as well as previously applied coats of paint. 

Time Limitations

Apply a prime coat to steel that is blast cleaned in the field within 12 hours of beginning abrasive blasting.  This requires that the time and location the blasting started is accurately documented.  This requirement is extended to 24 hours for shop blasted steel as it is a more controlled environment. 

The maximum elapsed time allowed between the application of any portion of the prime coat and the application of the intermediate coat is 30 days.  The maximum elapsed time allowed between the application of any portion of the intermediate coat and the application of the finish coat is 13 days.  The maximum recoat times shall not exceed the maximum recommended times by the manufacturer.  Extending the time beyond the above mentioned time could adversely affect the bond of the coating.  No additional time is allowed due to weather related delays.  Any coat that has been allowed to cure more than the above listed time is to be removed and the steel re-blasted to SSPC S-P10.

Enclosure

During spray application of the paint, the operation is to be totally enclosed.  The enclosure must be identical to the enclosure used during the abrasive blasting operation.  Failure to properly utilize the enclosure could result in overspray damage to private property, including automobiles, the ground, public property, vegetation, streams, lakes, etc.  The enclosure is not required if the paint is being applied by brush or roller.

Prime, Intermediate, and Finish Coat Application (QCP #5, # 8, and # 10) (514.17.G)

Each coat of paint is to be applied as a continuous film of uniform thickness.  It is to be free of all defects, such as holidays, pinholes, mud cracking, checking, runs, sags, etc.

Many time holidays in the form of pinholes are difficult to detect.  The best way to view pinholes is with the aid of a flashlight.  The flashlight should be placed to shine a beam of light parallel to the painted surface.  If pinholes are present in the top coat, they will appear as small white specs about the size of the end of a needle.  If they are present in the intermediate coat, they will appear as small dark specs. 

Note: If you are painting over an inorganic zinc primer, you should play close attention to pinholes appearing in the intermediate coat.  The inorganic zinc has an inherent characteristic of “outgassing” due to its porous nature.  The released gas pushes up through the intermediate coat and causes the pinholes.  To avoid the majority of pinholes in this situation, the Contractor should properly apply one or multiple mist coats of intermediate paint prior to the remaining full application.    

Repairing pinholes can be very difficult.  Applying another coat of paint over the pinholes will only result in the pinhole reflecting through the additional coat of paint.  It is the Contractor’s responsibility to repair the pinholes.  The best way to correct pinholes is by removing the coating down to at least the prime coat of paint.  If the prime coat is not removed, measurements should be taken to ensure that the required minimum thickness of prime paint is still present.  If the Contractor elects to leave the prime coat, he will probably remove the topcoats with sand paper.  If a large area needs to be repaired, it will probably be more prudent for the Contractor to abrasively blast the coating down to bare metal and reapply it.

Runs and sags are normally prevalent around bolts and areas of limited access.  This is sometimes due to the fact the Contractor tries to paint these areas using only a spray gun (i.e., without the use of a brush).  These defects should be corrected after each coat is applied.  If not, the defect will just translate into the next coat and the repair will be more extensive.

Removing Fins, Tears, or Slivers (514.18)

This item is paid for by the man-hour.  The quantity of man-hours eligible for payment should not include the superintendent or the QCS, but only the personnel who actually perform the work.

Caulking (514.19)

All gaps greater than 1/8 inch need to be caulked.  Caulking is used to seal gaps around the perimeter of adjacent steel plates and angles.  This void is caused by rust forming between the plates or angles and forcing them apart to the extent that it is not possible to seal the void with paint. 

Caulking materials appear on the Qualified Product List (QPL) maintained by the Office of Material Management (OMM). 

Dry Film Thickness (514.20)

Prior to measuring coating thickness, it is necessary to determine the effect of the blasted surface of the steel on the paint gauge.  Since the steel receives a profile of 1.5 to 3.5 mils (40 to 90 μm), the paint gauge will read high.  To compensate for this additional height, it will first be necessary to take a reading on the blasted surface immediately prior to applying the prime coat. Preferably three or more readings should be taken and averaged out.  This average reading should then be subtracted from all paint film thickness readings.  As an alternate to subtracting the thickness attributed to the surface profile from the paint film thickness, recalibrating the paint gauge to read 0 mils on the blasted steel is also acceptable.

It is important to determine the coating thickness by taking the average thickness in the manner specified in the specifications.  This involves taking five spot readings for each type of member (e.g., webs, bottom of top flange, top of bottom flange, bottom of bottom flange, cross-frames, stiffeners, etc.) over an area of 100 square feet.  A spot reading is comprised of the average of three closely-spaced, individual readings. The average reading for this 100 square foot area may be used to represent up to 1,000 square feet of painted steel surface.  The number of 100 square foot areas to be measured is determined by the area of steel painted.  Form CA-S-2 should be used to tabulate the results.

The spot averages are to be within 80 percent to 150 percent of specified minimum and maximum thicknesses, respectively.  The area averages must fall within the actual specified minimum and maximum values. 

There are provisions in the specification for addressing areas with a film thickness greater than the maximum specified.  If a Contractor chooses to have the certified testing done as described in the specification, make sure the preparation of the panels mirrors the actual field installation of the paint in question.  This includes paint thickness, multiple or mist coats, as well as type and quantity of thinner used.  The Painting Contractor and Paint Manufacturer must submit certified test data and a written statement from the paint manufacturer stating that the excessive thickness will not be detrimental to the overall coating system to the Office of Construction Administration. If they don’t submit this information, or the Office of Construction Administration does not accept the excessive coating thickness, the painting contractor must remove the coatings down to the bare steel per C&MS 514.22.

Final Inspection (514.21)

The purpose of the final inspection is to ensure that the quality of surface preparation and coating thickness are witnessed by a third party.  This third party could be the project engineer, area engineer, or other District personnel.

The Engineer will select the locations and take the dry film thickness (DFT) readings.  The Contractor will then perform the removals.  The 9 square inches required by the specification is the minimum “clean” area of steel.  It normally takes about a 6 inch by 6 inch square to get 9 square inches of “clean” steel.  The Contractor will use Methylene Chloride and MEK as a chemical stripper/solvent.  These chemicals are both corrosive and the safety precautions found on the MSDS sheets and manufacturer’s literature need to be followed.

A common stripping procedure is as follows:

1.        Spray surface with stripper.

2.        Wait 5 to10 minutes to allow the stripper to work.

3.        Use a scraper or putty knife to remove top coat and intermediate coat. It may take multiple applications of the stripper to accomplish this.

4.        Spray the exposed primer with stripper and allow time to work.

5.        Scrape off majority of primer. Be careful not to damage the substrate.

6.        Repeatedly apply solvent or stripper and rub with a rag until steel substrate is clean.

This process takes about 15 minutes for each stripped area. Work on other areas while the stripper sits.  It is imperative that the Engineer observe the removal process as the stripper and a scraper can remove lead paint as well as new paint. 

The engineer will evaluate the stripped area and document his findings on Form CA-S-18.

If the surface of the stripped area is not found to be in complete conformance with the Contract documents, additional locations may be tested.  Note: the Contractor is only paid for stripped areas that are found to be in conformance with the Contract documents.

Once all the required tests have been performed, and the progressive project data has been reviewed, the Engineer should complete Form CA-S-19.

Destructive test locations shall be repaired per 514.22.

Repair Procedures (514.22)

If it is necessary to make repairs, the repair should blend in with the surrounding area so that it is not evident that a repair was made.

If the area to be repaired does not cover a large area, abrasively blasting the surface may not be advisable since it will damage the surrounding coating that does not need to be removed.  In place of using abrasives, the Engineer may allow alternate methods of preparing the surface.  This might include the use of power tools with abrasive bits or hand tools.  Whatever method is used, it is still necessary to prepare the surface in a manner that will give a surface profile of 1.5 to 3.5 mils (40 to 90 μm).

In order to produce a smooth transition, it is necessary to feather the adjacent coatings.  This cannot be accomplished through the use of abrasives.  The new coat of paint should only be applied to the same coat that was feathered (i.e., the prime coat should only be applied to the feathered prime coat, the intermediate coat should only be applied to the feathered intermediate coat, and the finish coat should only be applied to the feathered finish coat).  Applying the finish coat to an existing finish coat that has not been feathered, or in any other way abraded, will result in finish with a dull, frosty appearance instead of a bright, glossy finish.

All work limitation and documentation requirements are in effect when surface preparation is performed and paint is applied.

Documentation Requirements - 514 Painting of Structural Steel

Material Data Sheets and TE 24’s for Inorganic Zinc Silicate Primer Paint per 708.01.

Material Data Sheets and TE 24’s for Organic Zinc Prime Coat, Epoxy Intermediate Coat, Urethane Finish Coat per 708.02.

Material Data Sheets for abrasives and thinners, if used.

Copy of the Quality Control Specialist’s and Superintendent’s Work Type 26 – Structural Steel Painting Course certificate, (Course taken within the last 4 years). 

Material Data Sheets for Caulk, single pack moisture cured polyurethane from OMM’s QPL

Provide signed documentation of inspection, testing, conditions, and material information to the Engineer on the following ODOT forms or forms with the equivalent information.

1.        Document Dry Film Paint Thicknesses on Form CA-S-2.

2.        The Quality Control Specialist must fill out and sign form CA-S-7 prior to all Quality Control Point inspections.

3.        Document the Quality Control Specialist’s information and the Job Site Visual Standards on Form CA-S-11.

4.        Document Solvent Cleaning (QCP#1) and Grinding of Flange Edges (QCP#2) on Form CA-S-12.

5.        Document Abrasive Blasting (QCP#3) on Form CA-S-13.

6.        Document Waste Disposal (QCP#4) on Form CA-S-14.

7.        Document Prime Coat Application (QCP#5) on Form CA-S-15.

8.        Document Grinding Fins and Slivers (QCP#6) and Caulking (QCP#9) on Form CA-S-16.

9.        Document Intermediate Coat Application (QCP#8) or Finish Coat Application (QCP#10) on Form CA-S-17.

10.     Document the Final Destructive Tests on Form CA-S-18.

11.     Document the Final Acceptance (QCP#11) on Form CA-S-19.

515 Prestressed Concrete Bridge Members

Fabrication Tolerances (515.17)

Sweep

Specified tolerances for sweep or horizontal curvature of a prestressed box beam or I -beam are listed in the Office of Structural Engineering's standard drawing for I beams.  I-beams are 1/8 inch every 10 feet with a maximum of 1 inch.

Box beam tolerances are 3/8-inch maximum for box beams 40 feet or less, 1/2-inch maximum for box beams 40 to 60 feet, and 5/8-inch maximum for box beams greater than 60 feet.

Camber

Camber is based on the design plan requirements and is generally within a tolerance of a 1-inch maximum.  Box beams also have a maximum side-by-side differential camber of 1/2 inch.  The side-by-side differential may override the 1-inch maximum camber tolerance for an individual member.  The side-by-side differential camber is not checked by laboratory prestressed inspectors as the beams are not installed in their final position.

Phased construction can cause unique problems with camber.  Camber is time dependent: as the members get older they will gain camber.  If all beams are manufactured for a bridge at the same time but only half are shipped for an initial phase of construction there is a good probability that the second phase beams will have a higher camber than the first-phase beams.  For box and I beam structures this additional camber may be able to be absorbed by thinning the haunch or variable depth deck.  Field loading of the field-installed beams to reduce the camber is a method some Contractors have used to deal with the camber growth.  The best methods are for the Contractor to order the beams early enough so none of the beams are erected and loaded before they are six months or older, or to coordinate their and the fabricator’s schedules so that the fabricated age of the beams at time of erection is within 30 days of each other for all phases. 

Handling, Storage, Transportation, and Erection (515.18)

Field Inspection

When prestressed members arrive on the site, they should be inspected for damage and quality of fabrication as thoroughly as time and conditions permit.  Inspection should include areas that look like they were patched and cracking.  Fine cracking at the ends of the beams, whether box beams or I beams, is not unusual and will tighten under erection and dead loading of the members.  Cracking in other locations is not usual or acceptable.  Any prestressed members should have a certification document (TE-24) with the shipment.  Do not accept un-documented members.  Notify the District Engineer of Tests or the Office of Materials Management Cement and Concrete Inspection Section. 

Erection components for prestressed box beam members (i.e., tie rods, splices, nuts, etc.) will be considered included under and covered by the fabricator’s certification document.  For I-beams the embedded components will be covered under the fabricator’s certification document.  If galvanized cross-frames are used for prestressed I-beams, the prestressed fabricator will probably not supply a certification document; they will be provided by a steel fabricator with separate certification documentation (TE-24).

Damage

The nature and extent of any damage which may have occurred because of loading, transit, or unloading should be noted and reported to the Director along with the identifying piece mark or member. If corrective work is obvious, the Contractor should be advised immediately so that the responsible party will be notified and correction can be performed in the most advantageous location.  For help on possible corrections, patching repairs, etc., contact the Cement and Concrete section of the Office of Material Management.

Special care should be taken when cutting shipping tendons which are sometimes necessary to allow transport of AASHTO Type 4 modified beams.  The location of these tendons as well as the sequence and means of removal are determined by the fabricator.  The relaxation in the beam that occurs when the tendons are “released” can induce stress cracking in the beam.

Storage

Prestressed members, if stored on the site, will be supported off the ground on blocking at their design bearing points.  Ensure that members are stored in a true vertical position.

Shop Coatings

Box beams should have had a silane treatment on the exterior beams or they also may be delivered with a colored coating (generally epoxy urethane) on the exterior members.  I-beams do not require a silane sealer and will generally not be coated at the fabricator’s yard

Check of Bearing Seats

A final check must be made of the elevation of bearing seats on the piers and abutments before erection of prestressed members is scheduled to begin. If bearing seats are found that need correction, it must be performed in the manner and to the tolerances described in the section entitled, Bearing Seats, in Section 511 of this manual.

Erection

The erection plan submitted by the Contractor should be reviewed with his representative in charge. The purpose of this review is to ensure that ODOT’s interpretation of the plan is concurrent with the Contractor’s intended course of action.  Methods and equipment approved for erection of members must be used in handling during transportation to the bridge site and unloading.

The erection drawings, usually the “E” sheets of the approved shop drawings, will typically be used to locate the members on the bridge and may give special instructions for the erector to follow.

Deviations from the submitted erection procedure will not be permitted. If the erector proposes deviations in the procedure that appear to have merit, they must be referred to the Engineer(s) whose stamp is on the submitted plan for review and sign off prior to use.

Required Erection Procedures

The specifications require that the Contractor submit an erection procedure for structural concrete members.  If there is railroad involvement, the PE stamped plan needs to be reviewed and approved by the appropriate railroad.  Otherwise, the plan must have two PE stamps.  For additional requirements, refer to C&MS Item 501.05.

Typical Erection Procedures Items

Typical items that should be included in the submitted erection procedure are:

1.        A drawing of the complete framing plan showing each girder or beam section by “piece mark” and numbered in the order of proposed erection. A print of the erection sheet of the shop drawings may be used.

2.        The number of pieces and load capacity of erection equipment to be used and method of lifting members.

3.        Methods and details for supporting the first beams or girders at the abutments and piers in each unit.

4.        Cross-frame installation.

Use Erection Checklist Form CA-S-20.

Box Beam Grout Installation

Keyways should be grouted after erection of box beams.  Generally, plastic rope or jute is installed into the bottom of the keyway to block the grout from flowing out.  Ensure that the installation is done properly.  Box beam keys have failed because of improper jute installation.  Grout should meet the material requirements of the Office of Structural Engineering's standard box beam drawings.  OMM has an approved list of grout materials.  The manufacturer’s mixing instructions are required and should ensure that the grout is properly mixed, vibrated into the joints, cured, and sampled for testing.  Grouting should not be allowed if there is construction traffic or erection still going on.  The grout can be cracked by the vibration and deflection movements and make the keyways worthless.  The design of the structure counts on the grout in the shear keys.

Do not allow traffic on the deck before the grout has obtained the required strength.  This includes construction traffic. 

Galvanized Cross-Frame Installation

Galvanized cross-frame for prestressed I-beams should not be tightened until the adjacent beams are set.  While bolts are high-strength, the connections are not friction type.  The bolts should be well tightened, but the turn-of-the-nut method of installation is not required.  If there are cross-frame alignment problems, do not allow I-beam field drilling until the Contractor has a method approved by the Engineer to determine where the reinforcing and the prestressing strands are and how to avoid drilling into it.

Do not allow the Contractor to elongate or enlarge slots in the steel cross-frames.

Documentation Requirements - 515 Prestressed Concrete Bridge Members

Records must be on file for the following items:

1.        Shop inspected prestressed members documented by a TE-24.

2.        Shop drawings per C&MS 501.04.

3.        Bearing seat inspection.

4.        Elastomeric bearings accepted.

5.        Document condition of beams on delivery.

6.        Beams set according to erection procedure per C&MS 501.05.B.4 and 515.19.

7.        Grout mixed per manufacturer’s directions.

8.        Make samples for testing.

9.        Document vertical offset in adjacent beams per standard drawing PSBD-1-93.

516 Expansion and Contraction Joints, Joint Sealers and Bearing Devices

The allowable procedures for the repair of metalized and galvanized surfaces are described in C&MS Item 711.02, which refers the reader to ASTM-A-780.  The use of a galvanizing spray with zinc dust is not allowed.  These unacceptable products go by the name of Spray Galv or Cold Galv.  The main problem with these products is that they don’t provide the galvanic protection that is required.  Most of them are made out of tin and lead in place of zinc.  When zinc and carbon steel are in contact, the zinc sacrifices itself to protect the steel.  Conversely, when tin or lead are in contact with the steel, the steel sacrifices itself for the tin and lead.

Expansion and Contraction Joints (516.05)

It is important that the gap set between the armor plates of the joint be consistent along the entire length of the joint.  The gap determined for the joint must be adjusted for temperature.  The joint manufacturer will supply a table to help calculate this adjustment.  This is especially true for more complex joints. 

The characteristics of the structure (e.g., skew, crown, super elevation, sidewalk, etc.) can lead to a complicated installation of the joints.  The Contractor should not weld anything to the joint or the reinforcing steel.   

Joints, like strip seal, compression, and modular, which incorporate a rubber seal into their design, need to have the seals installed per the manufacturer’s written instructions.   They should utilize tools that will not cut or puncture the seals.  It is not acceptable to elongate or stretch the seal in order to make it narrow enough to fit in the joint gap.

For Integral and Semi-Integral Abutment Expansion Joint Seals, the Contractor must install a 3-foot wide neoprene sheet for waterproofing the backside of the joint between the integral backwall and the bridge seat at locations shown in the plans. The neoprene sheeting is secured to the concrete with 1-1/4 inch by No. 10 gauge (length × shank diameter) galvanized button head spikes through a 1-inch outside diameter, No. 10 gauge galvanized washer. Maximum fastener spacing is 9 inches. Use of other similar galvanized devices, which will not damage the neoprene or the concrete, will be subject to the approval of the Engineer. The neoprene sheeting shall be 3/32-inch thick general purpose, heavy-duty neoprene sheet with nylon fabric reinforcement.

There are listings on the Qualified Product List (QPL) for items covered in C&MS Items 705.11 and 705.03.  This list is maintained by the Office of Materials Management.

Joint Sealers (516.06)

In addition to the protection required in the specification, the Contractor must ensure that the sawcut is not exposed to traffic prior to receiving the sealer without protecting the sawcut.  If the sawcuts are not protected, rocks or other hard debris can get lodged in the top of the sawcut, and when driven over the rock, will spall the edges of the sawcut. 

Bearing Devices (516.07)

Note: If the beam seats are low and elastomeric bearings are utilized, it is not acceptable to use steel shims under the bearing to make up the elevation difference.  Elastomeric bearing pads are to set directly on the concrete surface. If the beams seats are sealed with an epoxy or non-epoxy sealer prior to setting the bearings, do not apply sealer to the concrete surfaces under the proposed bearing locations. If these locations are sealed, the Contractor must remove the sealer to the satisfaction of the Engineer before setting the bearings. Contact the Office of Structural Engineering for guidance.  Many of the bearings have beveled load plates.  This is done to account for the grade in the structure.  Make sure the beveled bearings are oriented correctly.  Sometimes it is difficult to tell simply by looking at the bearing, as the difference may only be a 1/4 inch.  If the short side of the bearing is not already marked by the fabricator, measure the bearing and mark it in the field.

The Contractor must position rockers, elastomeric bearings, and rollers so that, when the completed bridge is at 60 °F (16 °C), the rockers and elastomeric bearings are vertical and the rollers are centered on the base. If the steel is erected at an ambient temperature higher than 80 °F or lower than 40 ºF and the bearing shear deflection exceeds 1/6 of the bearing height at 60 ºF ± 10 ºF, the Contractor must raise the beams or girders to allow the elastomeric bearings to return to their undeformed shape at 60 ºF ± 10 ºF.

Where the load plate of an elastomeric bearing is to be connected to the structure by welding, the Contractor must control the welding so that the plate temperature at the elastomer bonded surface does not exceed 300 °F as determined by use of pyrometric sticks or other temperature monitoring devices.

When galvanized bearings are welded to the embedded load plates on prestressed beams, the weld area must be repaired according to C&MS Item 516.03.

There is a listing on the Qualified Product List (QPL) for items covered in C&MS Item 711.21.  This list is maintained by the Office of Materials Management.

Documentation Requirements - 516 Expansion & Contraction Joints, Joint Sealers, and Bearing Devices

1.        Expansion and Contraction Joints.

a.        Expansion material placed and measured in appropriate unit per C&MS 516.08 and 516.09.

b.        Shop drawings per C&MS 501.04.

c.        Test Reports per 501.06.

2.        Joint Sealer.

a.        Area to be sealed clean and dry.

b.        Document depth of poured joints.

c.        Note types of bond breakers and bonding agents used.

d.        Sealers applied per manufacturer’s directions.

e.        Measure and pay in appropriate unit.

3.        Bearing devices.

a.        Shop drawings per C&MS 501.04.

b.        Test Reports per 501.06.

c.        Sliding plates lubricated with flake graphite.

d.        Lead sheets and bearing pads set to line and level.

e.        Rockers and rollers set vertical at 60 °F (16 °C) or adjusted for temperature.

f.         Anchor bolts placed to proper depth and alignment and set in mortar.

g.        Record quantity(s) and pay in appropriate unit(s) per C&MS 516.09.

517 Railings

The anchor bolts should be cast into the structure versus drilled and grouted into place after concrete placement.  This will alleviate drilling into the epoxy coated reinforcing steel.  Hold anchor bolts in place with the use of a template.  When the anchors are cast into the concrete, the threads should be protected from getting filled with concrete paste.

Failure to release falsework prior to installing railings could cause the railings to deform as the structure experiences the additional dead load deflections associated with the falsework release.

Any preformed PVC fillers or paint coatings used should be listed on the Qualified Product Lists (QPL) for Items 711.28 and 708.

Steel and Iron Railings (517.05)

If field welding is required on galvanized members, repairs should be made similar to C&MS Item 516.03.  Cold Galv or Spray Galv should not be used.

Documentation Requirements - 517 Railings

1.        Railing.

a.        Shop Drawings per C&MS Item 501.04.

b.        Test Reports per C&MS Item 501.06.

c.        Measure and record length of railing per C&MS Item 517.07.

d.        Ensure the fabricator has the required SF prequalification.

2.        Deep Beam Railing.

a.        When forming for deck, check bolt layout.

b.        Check height.

c.        Measure per C&MS Item 517.07.

518 Drainage of Structures

Porous Backfill (518.05)

Unless otherwise shown in the contract drawings, the Contractor is to provide a minimum of 24 inches of porous backfill behind the full-length of abutments, wing walls, and retaining walls.  The placement width is normally erratic due to construction means and methods.  Make sure the minimum width is maintained.  If the underdrain is at the footing elevation, the 24-inch dimension is measured from the edge of the footing, not the back face of the wall. If there are weep holes in the concrete, the Contractor must place 2 cubic feet of bagged No. 3 aggregate at each weep hole to retain the porous backfill.

Porous backfill is No. 57 size gradation; it must be compacted.  Even rounded No. 57 gravel is not self-compacting. 

It is imperative that the filter fabric used to encapsulate the porous backfill be continuous and properly overlapped.  The fabric gets flipped back and forth as the Contractor alternates from porous backfill to Type B granular.  Working the fabric in this manner can cause misplacement or tearing.  A non-continuous or misplaced layer of filter fabric allows the fine material to “pipe” into the porous backfill, which can lead to settlement and lack of drainage.

All drains should be free flowing.  They need to have a positive fall.  Special care needs to be taken when the drainage hangers, anchors, or pipes are attached to a structure prior to final dead load deflection.  As the bridge deflects, the grade of the pipes may be affected and cause stagnant or pooling sections of pipe.

Documentation Requirements - 518 Drainage of Structures

1.        Porous Backfill.

a.        Type of stone used.

b.        Pay in appropriate unit.

2.        Pipe.

a.        Metal pipe per various sections in 707.

b.        Plastic pipe per 707.33, 707.45.

c.        Laid to grade, outletted per plan.

d.        Measure each type per linear foot.

3.        Scuppers, structural steel, cast steel.

a.        Verify prequalification of fabricator to level SF.

b.        Shop drawings per 501.04.

c.        Test reports per 501.06.

519 Patching of Concrete Structures

Removal of Disintegrated Concrete (519.03)

It is essential that all unsound concrete be removed.  The use of a hammer will be necessary to sound tight areas, and the use of a sounding chain will speed up deck sounding.  The practice of removing additional sound concrete after the deteriorated material is removed helps to ensure a stable surface to pour against. 

Pay special attention to the locations at the edges of the patch where the reinforcing steel enters the sound concrete.  In many cases, during the removal process, the reinforcing steel is vibrated or impacted, which causes cracking around the reinforcing steel penetration point.  If this occurs, the Contractor will have to “chase” the cracks to make sure all fractured concrete is removed.

Placing, Finishing, and Curing of Concrete (519.06)

It is very difficult to get proper consolidation of a vertical patch.  It may be necessary for the Contractor to utilize a “pencil” vibrator and/or externally vibrate the forms to assist in consolidation.  In all cases, the Contractor is responsible to provide a well consolidated patch. 

Make sure all form ties and form attachment points in both the new concrete and the existing sound concrete are repaired after formwork removal.     

Documentation Requirements - 519 Patching Concrete Structures

1.        Document the patch depth of 4 inches (10 cm) for horizontal patches and the patch depth of 3 inches (8 cm) for vertical patches as per 519.03.

2.        Patch area thoroughly cleaned with water, compressed air, etc.

3.        Concrete testing data and batch tickets for Class S or QC-2 concrete, as specified in the plans. 

4.        Exposed area of patch given a rubbed finish and cured as per 511.14.

5.        Sound patches before final acceptance.

6.        Measure length and width for pay.

520 Pneumatically Placed Mortar

Description (520.01)

This item of work consists of repairing concrete structures by spraying the area to be repaired with dry, premixed sand and cement that is blended with water in a mixing nozzle.  The pneumatically placed mortar is then finished and cured.  This type of procedure is often referred to as “shotcrete” by the industry.

Reinforcement (520.04)

All existing reinforcing steel bars must have a minimum cover of 1 inch (25 mm).  If the existing location of the reinforcing bars would result in less than 1 inch (25 mm) of cover, they are to be driven back into recesses cut into the existing concrete to achieve that coverage.  If this is not practical due to the large number of reinforcing bars, the coverage must be obtained by modifying the finished surface.  If the reinforcing steel is epoxy coated, care should be taken to minimize the damage to the existing coating.

Where the depth of the patch exceeds 1-1/2 inch (38 mm), in addition to any existing reinforcing steel, wire fabric is required. Where the depth of the patch exceeds 4 inches (100 mm), a layer of fabric is to be placed for each 4 inch (100 mm) thickness of patch or fraction thereof. 

Preparation of Repair Area (520.05)

Prior to placement of pneumatically placed concrete, the area to be repaired must be properly prepared.  All soft, loose, and disintegrated concrete, plus an additional depth of 1/4 inch (6 mm) of sound concrete, must be removed. Failure to remove soft, loose, and disintegrated concrete will adversely affect the bond of the mortar and shorten the life of the repair.

The edges or shoulders of the repair areas must be square or slightly undercut.  If this is not accomplished, the mortar placed at the edges of the repaired area will be feathered.  These feathered areas will not have adequate strength and will scale off.  

After all concrete has been removed from the repair area, all dowels and expansion hooks placed, all steel areas restored, and no more than 24 hours prior to placement of mortar, the area to be repaired must be abrasive blast cleaned. The abrasive blast cleaning must be done to remove spalls, latence, and any other foreign material that might be detrimental to achieving a bond with the pneumatically placed mortar.  The Contractor should select an abrasive blast method that will control or minimize the amount of fugitive dust escaping into the atmosphere.  Suitable blast methods may include high-pressure water blasting with abrasives in the water, abrasive blasting with containment, or vacuum abrasive blasting. The Contractor must ensure that all wastes generated by the surface preparation operation are managed in accordance with 107.19.

Unless otherwise specified, the Contractor shall wet the area to be repaired with water for at least 2 hours prior to placing the mortar. The area must be kept wet until the mortar is placed.  At the time of placement of the mortar, all free water must be removed.

Preconstruction Testing (520.09)

Due to past experiences with pneumatically placed mortar that was improperly placed and prematurely failed, each operator must demonstrate their ability to construct a sound, durable repair prior to being allowed to place mortar on the structure.  This is accomplished by gunning the mortar onto a test panel.  The mortar on this test panel is then tested for strength and examined for hollow areas, sand pockets, and bond to the reinforcement.  The cores taken for compressive strength samples cannot contain any reinforcing steel.  If the reinforcing steel spacing is too tight to retrieve a non-reinforced core, it may be necessary to construct a portion of the test panel without reinforcing.  The easiest means to examine the test panel for mixing and consolidation issues is to pull a core at the intersection of the reinforcing steel or to simply saw the test panel in half.  It is important to look at the cross-section of the reinforcing steel, as the backside of the reinforcing steel is usually the most suspect area.  The test panel should be water cured for 7 days and handled in the same manner as a cylinder.  The sample should not be cored for at least 7 days and the cores should be handled in the same manner as a cylinder.

Placing (520.10)

Curing

After the mortar is placed, it must be cured. Curing shall consist of covering the patch with burlap or cotton mats and keeping them wet for 7 days.  If it is not practicable to use mats, the surface of the patch must be kept wet by sprinkling the surface with water for 7 days.  If it is determined that the above methods are impracticable due to isolated areas being inaccessible, they must be cured according to the requirements of 511.14, Method B.

Inspection and Testing (520.11)

After the curing of the patched areas is completed and before they are accepted, they must be sounded, and every 200 square feet (20 m²) cored.  All unsound areas, or areas that exhibit cracking, must be removed and replaced.  The cores must be inspected for hollow areas, sand pockets, voids around reinforcing steel, and lack of bond to the underlying concrete.  The cores are to be tested for compressive strength.  Any defective patches, as determined by the cores, must be removed and replaced at the Contractor’s expense.

Documentation Requirements - 520 Pneumatically Placed Mortar

1.        Unsound concrete removed plus 1/4 inch (1 cm).

2.        1 inch (2.5 cm) minimum clearance to reinforcing.

3.        1 layer wire fabric for each 4 inches (10 cm) of patch depth.

a.        Reinforcing fabric lapped 6 inches (15 cm) minimum.

4.        Surface cleaned by water or sand blast.

5.        Mortar composed of three parts sand to one part cement.

6.        Mortar placed as dry as possible.

a.        No one coat greater than 1 inch (2.5 cm) in thickness.

7.        Wet burlap cured 7 day minimum or membrane cured with Engineer approval.

8.        Inspect and test per 520.11.

a.        Sounding.

b.        Core taken for every 200 square feet of repair.

9.        Measure patch area and pay by the square foot (square meter).

522 Structural Plate Corrugated Metal Structures on Footings

Description (522.01)

This work consists of the sectional corrugated metal arch described in 522.  Excavation and concrete for structures are covered in 503 and 511.

Quality Control

The quality of galvanizing should be examined.  Some added thickness occurs at the bolt holes and may appear to be stripping when the bolts are installed.  Peeling, which is evidence of separation of galvanizing around bolts or near the edges of the plates, when pried with a knife or impacted with a hammer, is cause for rejection.

Corrugated metal arch structure plates, high strength bolts, ribs, and anchor angles should only be accepted from certified suppliers listed on the Office of Materials Management’s website.  The shipments should be accompanied by a certification document (TE-24).

Assembly

Certified suppliers must provide assembly and installation procedures with the shipment.  Shipments that do not include the assembly and installation procedures should not be accepted.

Documentation Requirements - 522 Structural Plate Corrugated Metal Structures on Footings

1.        Be sure bearing angle or channel is at proper alignment and grade.

2.        Bolts with required nuts and washers placed.

3.        Backfill per 611.06.

4.        Measure length for pay.

523 Dynamic Load Test

Description (523.01)

Except for H-piles driven to bedrock, bearing piles are driven to a required blow count to ensure that they have the ultimate bearing value shown on the plans. The relationship between the blow count and ultimate bearing value is dependent on many variables, including the pile type, material, and length; pile hammer energy and performance; and soil properties.  The simple formulas used in the past considered only one of these variables: pile hammer energy.  Dynamic load testing measures the energy going into the pile from the hammer and accounts for many of the different variables to estimate the capacity of the pile with each blow of the pile hammer.  The Department uses dynamic load testing to determine the required blow count for the ultimate bearing value on every project that includes driving bearing piles.

The methods used in dynamic load testing, also called PDA testing (named after the equipment: Pile Driving Analyzer), were developed in Ohio beginning in the 1960’s.  The Ohio Department of Transportation was involved early in its development and began to apply the results of the research in their construction projects around 1968.  Since 2002, the Department has used dynamic load testing for all pile driving (except piles driven to bedrock) and discontinued the use of the simple formula used previously.

General (523.02)

Each dynamic load test consists of dynamically testing a minimum of two piles.  If there are piles of different size, shape, or capacity, it will be necessary to perform dynamic load testing for each of these differing sizes, shapes, or capacities, and there should be additional pay items in the Contract to reimburse the Contractor for performing these tests.

Dynamic load testing is accomplished by connecting two sets of gauges to a pile. One set of gauges measures the strain in the pile at the top, while the other gauge measures the acceleration of the pile at the top.  These gauges are then connected to a computer called a Pile Driving Analyzer (PDA).  The PDA converts the measured strain and acceleration into force and velocity.  By analyzing the way the force and velocity change with time, the PDA estimates the pile capacity for each blow of the pile hammer.  After the PDA is connected to the pile, the Contractor begins driving the pile.

Once the dynamic load testing begins, the driving of the pile continues until the required ultimate bearing capacity is achieved.  At this time, the blow count, blows/ft (blows/meter), is noted.  It is necessary to record the stroke height of the hammer.  In addition to performing dynamic load testing, the Contractor is required to perform signal matching analysis of the dynamic test data on at least one of the piles tested.  The Contractor must perform the test according to ASTM D 4945. The signal matching analysis is a more refined analysis method that takes into account the properties of the different soil layers.  The results of the dynamic load testing and signal matching analysis are then used to establish the driving criteria required to achieve the ultimate bearing capacity for the remaining piles represented by this test.  Immediately after the dynamic load test has been completed, the personnel performing the testing must inform the Engineer of the required driving criteria.  This will include both the blow count and the stroke height.  Within 48 hours after completing the test, the Engineer is to be given a written report with the results.

Prior to allowing the test to begin, the personnel performing the test must supply the Engineer with a copy of a certificate showing that they have an Advanced Master or Expert Level Certification in High Strain Dynamic Pile Testing (HSDPT) from either the Pile Driving Contractors Association (PDCA) or Foundation QA.  The Foundation QA examination was the original certification program, but the Department is changing to the PDCA certification program.  Both certification programs are currently acceptable.  A sample certificate is shown below.  The Engineer can also check a person’s certification status on the following website:

 www.pdaproficiencytest.com.

Figure 523.A – Example PDA Testing Certificate

If the designers suspect that the capacity of the pile could increase or decrease after it has been in the ground for some period of time, an additional test called a restrike could be specified.  If a restrike is specified, the plans specify the minimum elapsed time from when the pile was driven until the time of the restrike.  This waiting period could be anywhere from a day to a week or more.  Each restrike test consists of dynamically testing a minimum of two piles, the same as the dynamic load test.

When a restrike is specified, it is very important that during the waiting period, the pile to be tested should not be disturbed in any manner until the PDA is properly hooked up and the test is ready to begin.  Disturbing the pile can cause the pile to partially or completely lose any change in capacity it has acquired during the waiting period.

The pile hammer used to restrike must be the same hammer used to perform the initial dynamic load test on the pile and must be thoroughly warmed up by applying at least 20 blows to another pile, other than the pile being tested, immediately before the test begins.  When the test begins, the first few blows are used to determine the capacity of the pile.  Any results obtained after the first few blows will result in the pile returning to the capacity it obtained prior to the required waiting period.

Documentation Requirements - 523 Dynamic Load Test

1.        File a copy of the field technician’s certificate which shows they have a current Advanced Master or Expert Level Certification in High Strain Dynamic Pile Testing from the PDCA or FQA.

2.        Document the initial driving criteria received immediately after the dynamic load test is performed.

3.        Receive a formal report within 48 hours, including the information required in 523.04 A-D.  Submit a copy of the report to the Office of Geotechnical Engineering.

524 Drilled Shafts

Description (524.01)

Drilled shafts are reinforced concrete columns, which, for the most part, are built below the surface of the ground.  They are designed to provide a foundation for structures and carry the entire load of the structure.  They are sometimes referred to in the field as caissons.

Contractor's Installation Plan (524.03)

Prior to installing drilled shafts, the Contractor is required to submit a written installation plan to the Engineer.  This plan should be closely reviewed for conformance with the specifications. Among other things, the plan should describe how the Contractor proposes to excavate the hole, clean out the hole, and place the concrete. The plan needs to include procedures for maintaining correct horizontal and vertical alignment of the excavation. The plan should also include procedures and the proposed equipment required to deal with the possible presence of and subsequent removal of underground obstructions within the hole excavations.

If a permanent casing is specified, the casing should be installed to the prescribed depth before excavation begins.  In some cases, the Contractor may not have the required equipment to completely install the casing prior to excavation.  If the Contractor is not able to completely install the casing prior to excavation, he is allowed to either excavate the material within the casing, or excavate a pilot hole ahead of the casing.  If the Contractor proposes to excavate the material within the casing to aid in the installation, it is important that the excavation does not proceed beyond the casing.

If the Contractor proposes to either pump or tremie the concrete under water while utilizing a temporary casing, his plan should describe how he proposes to remove the casing while not disconnecting or breaking apart the tremie or pump hose.  In order to ensure that the end of the pump or tremie hose is always embedded into the concrete, his plan should detail how he proposes to monitor the level of the top of the concrete and the bottom of the pump or tremie hose.  If the Contractor does not include these provisions in his plan, and encounters water in the field, he should be required to stop and resubmit a plan containing the necessary information.  He should not proceed with verbal approval as it is too difficult to document what was said versus what may have been intended.

Drilled shaft installation can be very complicated since a large amount of work is performed in an area with very little access.  The plan should be very detailed and site specific.  A generic or “canned” plan should not be accepted. 

Types of Drilled Shafts

There are two types of drilled shafts:

1.        End bearing.

2.        Friction. 

End bearing drilled shafts derive most of their capacity through end bearing on a hard substrate, such as bedrock.

Friction type drilled shafts derive most of their capacity through a combination skin friction with the soil along the perimeter of the drilled shaft and end bearing on the substrate immediately below the drilled shaft. To obtain the required skin friction, it is important that the integrity of the soil be maintained during the drilling operation and prior to placing the concrete.

Hole Excavation (524.04)

There are several different methods used to stabilize the sides of the excavation during the construction of the drilled shaft.  Factors that impact the method chosen are types of soil, the elevation of the ground water, types of drilled shafts, plan requirements, and equipment utilized by the Contractor. 

Dry Construction Method (524.04.A)

The dry construction method is accomplished by excavating the hole without the use of steel casing.  The sides and bottom of the excavation should remain stable and should not experience any caving, sloughing, or swelling.  It should be possible to visually inspect the excavation prior to the placement of concrete.

The excavation should be done in a relatively dry condition with very little ground water present.  The flow rate of any water that might enter the excavation should be such that the elevation does not change by more than 12 inches (300 mm) per hour.  At the time of concrete placement, there should be no more than 3 inches (75 mm) of water in the bottom of the excavation.  Both the flow rate test and the amount water in the bottom of the hole should be documented.

Wet Construction Method (524.04.B)

The wet construction method should be used at sites with or without casing and where a dry excavation cannot be maintained.  This method consists of using either water or slurry to contain or prevent the seepage of ground water into the drilled shaft.  With the use of slurry, this method may be used in place of a temporary casing to maintain the stability of the perimeter of the hole while advancing the hole to its final elevation.

If this method is used to excavate a hole for a friction-type drilled shaft, it is important to not compromise the integrity of the soil along the perimeter of the drilled shaft through the seepage of ground water.  It is not only important to prevent the seepage of ground water into the excavation after it is complete, but it is important to prevent ground water from seeping into the excavation during the drilling process.  To prevent this, it will be necessary to continually pump either water or slurry into the hole during the drilling operation to maintain an elevation slightly higher than the elevation of the static water table.

Either a tremie or a concrete pump will be used to place the concrete when the wet construction method is used.

Unless waived by the Engineer, it is required for the Contractor to use a temporary surface casing to prevent soil at the top of the casing from sloughing and falling into the excavation. This casing should never be shorter than 10 feet (3.0 m) long.  The temporary casing aids in the proper alignment and positioning of the drilled shaft. 

Temporary Casing Construction Method (524.04.C)

Temporary casing may be used at sites where dry excavation cannot be maintained and the Contractor elects not to use slurry.

It is important that the Contractor begins removal of the temporary casing while the concrete remains workable.  Failure to remove the casing could result in a drilled shaft that is not capable of supporting the design load.

When the casing is withdrawn, there is a possibility that fluid trapped behind the casing will contaminate the concrete.  To prevent this, it is important to maintain a head of concrete at least 5 feet (1.5 meter) in the casing.  This minimum head may need to be increased to counteract any ground head that might be in the casing at the time it is withdrawn.  Casing should be removed by pulling at a slow uniform rate.  However, if the casing gets stuck, the Contractor may rotate, vibrate, or tap the casing to facilitate extraction.  Rotating the casing may twist the reinforcing cage, so only rotate the casing enough to get it unstuck.

Friction Type Drilled Shafts (524.05)

Friction-type drilled shafts derive much of their capacity through the adhesion of concrete with the surrounding soil.  If the Contractor elects to use a temporary steel casing and fails to remove it, or he fails to protect the integrity of the soil adjacent to the drilled shaft, much of the capacity of the drilled shaft could be lost.

When drilled shafts extend below the top of the water table, it is important that the water or slurry fluid inside the shaft excavation be maintained higher than the top elevation of the water table at all times. To accomplish this, it is not only important for the Contractor to add water or slurry fluid after the excavation is complete, but it is also important for him to add water or slurry fluid during the drilling operation.  If this is not done, the surrounding ground water will begin to enter the excavation and erode the soil.  This will result in the reduced capacity of the drilled shaft.

The dry construction method can be used in construction of friction-type drilled shafts.  It should be used when the bottom of the drilled shaft is above the water table and the excavation can be made without the sides or bottom of the excavation experiencing any caving, sloughing, or swelling.  If the dry construction method results in the sidewall becoming softened or swelling, the Contractor shall over ream the sidewall to sound material.

If the Contractor elects to use slurry, a delay in placing the concrete could result in the sidewalls degrading due to slurry cake buildup.  Any slurry cake buildup shall be corrected by reaming the sidewalls to sound material.

If a temporary casing is not used, and concrete is not placed the same day that the excavation is complete, the excavation shall be re-drilled 6 inches (150 mm) larger in diameter immediately prior to the placement of the concrete.

Casings (524.06)

If a temporary casing is used, it should be smooth and free of dried concrete and other foreign materials that might contaminate the fresh concrete.  While the strength and thickness of the steel casing is not specified, it should be strong enough to withstand handling, installation, and extraction stresses as well as the pressures exerted on it by the fresh concrete and surrounding earth.

The outside diameter of the casing should be at least equal to the plan diameter of the drilled shaft.  Many times the Contractor will elect to use a casing larger than the specified casing.  Oversized casings are acceptable; however, all additional costs associated with the oversized casings should be borne by the Contractor. 

Typically, the diameter of the bedrock socket will be less than the diameter of the remainder of the drilled shaft.  When the diameter of the bedrock socket is the same as the remainder of the drilled shaft, the diameter of the drilled shaft may need to be increased to permit the excavation of the bedrock socket.  Again, increasing the diameter of the drilled shaft should be done at no additional cost to the state.

Slurry (524.07)

One potential method of excavating a hole through unstable or caving soils is through the use of slurry.  The slurry should be added to the excavation during the drilling process and replace the material that is being removed.  This is accomplished by mixing the slurry with the material to be removed.  The combination of slurry and soil is then pumped from the hole while clean slurry is added.  The slurry that was pumped from the hole is then cleaned of foreign material and placed back into the hole.  This process is continued until the original soil has been removed.

There are two different types of materials used to produce slurries.  One type of material produces mineral slurry and the other type of material produces polymer slurry.

If the Contractor elects to use polymer slurry, he must first demonstrate the slurry's ability to prevent caving of the hole.  If the slurry is not capable of stabilizing the perimeter of the hole while the hole is being excavated, it should not be allowed. This should be accomplished by the use of a separate trial hole.  This trial hole should not be one of the production shafts and no separate payment should be made for the trial hole. The trial hole should be the same size and diameter as the largest production drilled shaft except the depth of the hole need not be more than 40 feet (12 meters).  The slurry used in the trial hole should be the same as that used in the production shafts.

Excavation Inspection (524.08)

An important factor in the performance of the drilled shaft is the cleanliness of the hole excavation prior to the placement of the reinforcing steel and the concrete. The Contractor must provide equipment to check the dimensions, alignment and cleanliness of the hole excavation.

Reinforcing Steel for Drilled Shafts (524.09)

Reinforcing should be placed just prior to concrete placement.  It should be placed as one continuous cage.  If a casing is not used, care should be taken when lowering the reinforcing steel cage into the shaft so it does not drag down the face of the shaft and compromise the integrity of the exposed soil surface.

Spacing devices, commonly referred to as “donuts,” need to be installed at quarter points around the shaft to ensure that the required concrete cover is obtained.  On the bottom of the shaft, the Contractor can use plastic “shoes” to keep the reinforcing cage at the proper elevation.  These shoes are normally 6 inches (152 mm) to 8 inches (203 mm) tall and about as big around as a soda can. In the past, mortar blocks were wired to the end of longitudinal steel to accomplish this task, but were unstable and the cage often fell off the blocks.

Concrete for Drilled Shafts (524.10)

The concrete used in the drilled shaft is Class QC 2.  In order to aid the consolidation of the concrete without vibration, it is necessary to increase the slump to 6 inches (150 mm) ± 1 inch (25 mm).  If the concrete is placed using a tremie, the slump should be increased to 8 inches (200 mm) ± 1 inch (25 mm).  The accepted JMF’s maximum water-cementitious ratio shall not be exceeded. It may be necessary to achieve the additional slump through the use of a super-plasticizer.

If the Contractor uses the wet method or places concrete under water or slurry, increase the cement content by 10 percent and place the concrete by either tremie or concrete pump. 

If a temporary casing is used, it should be removed slowly and carefully.  As the casing is removed, concrete that has been previously placed will fill the void left by the casing thus causing the top level of the concrete in the excavation to lower.  As the level of the concrete drops, the concrete will tend to pull down on the reinforcing steel.  If the casing is removed too quickly, the downward force of the concrete on the reinforcing steel will cause the reinforcing steel to be displaced.

Tremie (524.12)

A tremie may be used to place concrete in a wet hole.  If concrete is placed in a wet hole, it is important that the concrete not be placed into moving water.  If concrete is placed into moving water, the water will have a tendency to wash the cement off of the sand and aggregate.  To prevent moving water in the excavation, the level of water or slurry in the excavation must be equal to or higher than the level of the ground water. 

The tremie must not contain aluminum parts that will come into contact with the concrete.  In order for the concrete to pass freely through the tremie, the minimum diameter of the tremie shall be at least 10 inches (250 mm).  It is important that the tremie be clean, smooth, and free of built-up concrete and other foreign material.

Prior to placing the tremie tube into the water, it is important to plug the end of the tremie to prevent the intrusion of water into the tremie.  The tremie can be placed into the excavation after the plug is in place.  After the tremie is filled with concrete, it should be raised up no more than one diameter of the tube.  This allows the plug to be displaced and the concrete to begin flowing into the excavation.  If the tremie is not plugged, the tube will fill with water.  When the concrete is dropped through the tube, it would drop through the water which separates the cement from the sand and gravel.

During the placement of the concrete, the end of the tremie should always be at least 10 feet (3 meters) below the surface of the concrete to prevent the water from contaminating the fresh concrete.  It is important to devise a method to determine elevation of the top of the concrete and the bottom of the tremie since the concrete will be under water and not visible.  This method should be determined and agreed upon with the Contractor prior to the concrete’s delivery. 

In order to prevent air voids in the concrete when a tremie or pump is used, place the concrete in one continuous operation.  If the Contractor is allowed to break apart the tremie tube or pump hose to facilitate the removal of temporary casing, the tremie tube or pump hose could get air voids in them that will be forced down into the drilled shaft concrete. If the end of the tremie is pulled out of the concrete prior to completely placing all the concrete, the drilled shaft will contain concrete that will be contaminated by water.  As a result, the drilled shaft may not have the required strength and should be considered defective.

After the concrete placement has been completed, there will be a layer of concrete at the top of the drilled shaft called, “laitance,” that has been contaminated with water.  This concrete should be removed either by overfilling the drilled shaft and causing the contaminated concrete to flow out of the drilled shaft or by shoveling off the concrete.  If the contaminated concrete is shoveled off, the Contractor must place additional concrete to replace the concrete that was shoveled off.

Pumped Concrete (524.13)

A pump may be used to place concrete in a wet hole.  If concrete is placed in a wet hole, it is important that the concrete not be placed into moving water.  If concrete is placed into moving water, the water will have a tendency to wash the cement off of the sand and aggregate.  To prevent moving water in the excavation, the level of water or slurry in the excavation shall be equal to, or higher than, the level of the ground water. 

Due to the adverse reaction of concrete with aluminum, the pump must not contain aluminum parts that will come into contact with the concrete. 

In order to allow the concrete to pass freely through the pump, the minimum diameter of the pump pipe must be at least 4 inches (100 mm). 

During the pumping operation, the pipe used to convey the concrete to the bottom of the drilled shaft must be anchored to the steel casing or other suitable stationary object to prevent the pipe from undulating.  Otherwise, the tendency of the pipe to undulate could cause it to pull out of the concrete that was previously placed.

In order to lubricate the pump equipment, grout should be first pumped through the hose prior to pumping the concrete.  The grout should not be placed in the drilled shaft.  This process does not need to be repeated as long as the process is continuous.

Prior to placing the pump pipe into the water, it is important to plug the end of the pipe to prevent the intrusion of water into the pipe.  After the plug is in place, the pipe can be placed into the excavation.  When the pipe is filled with concrete, the pressure of the concrete will dislodge the plug.  If the pipe is not plugged, and the concrete drops through the water, the water would separate the cement from the sand and aggregate.

During the placement of the concrete, the end of the pump pipe should always be at least 10 feet (3 meters) below the surface of the concrete to prevent the water from contaminating the fresh concrete.  It is important to devise a method to determine elevation of the top of the concrete and the bottom of the pipe since the concrete will be under water and not visible.  This method should be determined and agreed upon with the Contractor prior to the concrete’s delivery to the project.

In order to prevent air voids in the concrete when a tremie or pump is used, place the concrete in one continuous operation.  If the Contractor is allowed to break apart the tremie tube or pump hose to facilitate the removal of temporary casing, the tremie tube or pump hose could get air voids in them that will be forced down into the drilled shaft concrete.

If the end of the pipe is pulled out of the concrete prior to completely placing all the concrete, the drilled shaft will contain concrete that will be contaminated by water.  As a result, the drilled shaft may not have the required strength, and should be considered defective.

After the concrete placement has been completed, there will be a layer of concrete at the top of the drilled shaft called, “laitance,” that has been contaminated with water.  This concrete should be removed either by overfilling the drilled shaft and causing the contaminated concrete to flow out of the drilled shaft or by shoveling off the concrete.  If the contaminated concrete is shoveled off, the Contractor must place additional concrete to replace the concrete that was removed.

Inspection Records (524.15)

It is the Contractor's responsibility to provide the Engineer with all the necessary labor and equipment to obtain measurements of the drilled shaft.  Since it is not possible to obtain these measurements after the concrete is placed, it is necessary to obtain these measurements prior to placing concrete.

Due to the risks involved, at no time should the Engineer ever go down into a drilled shaft for inspection or any other purpose.

A copy of form CA-S-1 should be filled out and submitted to the Office of Geotechnical Engineering.

Method of Measurement (524.16) and Basis of Payment (524.17)

The pay length of the drilled shaft is the required, accepted length measured along the axis of the shaft.  It should be measured from the required bottom of the shaft to the proposed top plan elevation.  Any over excavation below the required bottom of the shaft should not be measured for payment. 

Drilled shafts that extend into bedrock should be divided into two sections.  The lower section is the length of the drilled shaft that extends into the bedrock or the bedrock socket.  The upper section is the length of drilled shaft above the bedrock.  If the top elevation of the bedrock is lower than indicated on the plans, the additional upper section or length of drilled shaft above bedrock should be measurement for payment.  The Contractor should not be paid for any over excavation of the bedrock unless he is ordered to do so by the Engineer.

Documentation Requirements - 524 Drilled Shafts

1.        Review Contractor installation plan.

2.        Holes accurately located to line and spacing.

3.        Documentation of flow rate of ground water into shaft to validate Dry Construction Method.

4.        Fill out form CA-S-1.

5.        Document drilling method: dry, wet, temporary casing, or permanent casing.

6.        Slurry use per 524.07.

7.        Shaft excavation clean on bottom.

8.        Reinforcing steel cleaned.

9.        Placement of reinforcing steel, center alignment with spacers, clearances, plumbness, etc.

10.     Note concrete placement method: pump, tremie, or free fall. (524.10-524.13).

11.     Notify Engineer when unexpected obstructions are encountered.

12.     Measure and pay per 524.16 and 524.17.

526 Approach Slabs

Description (526.01)

An approach slab is designed to function as a bridge deck spanning the distance from the bridge abutment to beginning of the roadway pavement.  As a result, it is designed and constructed similar to a bridge deck.

Materials (526.02)

The concrete used to construct the approach is the same class as the bridge deck and should be placed using the same specifications as the bridge deck concrete. If the project does not identify the class of concrete used for the superstructure, or if the deck is composed of prestressed box beams with an asphalt-wearing surface, Class QC-2 or Class S concrete, depending on the quantity required for the approach slab, should be used.

Setting Grades

It is important that the approach slab be constructed parallel to the surface of the bridge deck to provide a smooth ride from the approach pavement to the bridge deck.  To accommodate the actual dead load deflection of the deck, which may vary from the anticipated dead load deflection, the approach slabs should not be placed until after the deck has been placed. However, in an attempt to achieve a smoother ride, District Bridge Engineers have allowed Contractors to place the approach slabs continuously with the bridge decks, especially for some semi-integral and integral abutment designs. Some things to consider if the approach slabs are placed continuously with the bridge deck:

1.        Placing the deck and the approach slab together would not allow the installation of the Type A Waterproofing per Bridge Standard Drawing AS-1-81.

2.        Adjacent spans with large deflections, over 1 inch, could cause the semi-integral or integral abutment diaphragm to rotate on the bearing, which could cause the D800 bar in the continuously placed approach slab to move and damage the approach slab where the concrete's initial set had already began. Therefore, concrete placement sequences may be required, such as starting at the rear abutment, placing concrete in the bridge deck and continuing across the forward approach slab, then coming back and placing concrete in the rear approach slab.

3.         Approach slab concrete cannot be placed with bridge deck concrete if semi-integral or integral abutment diaphragm concrete placement for steel members or prestressed concrete members is not done prior to concrete deck placement.

4.        Permit the placement of the approach slab with the bridge deck for integral or semi-integral designs if:

a.        The skew is less than 10 degrees for prestressed concrete beams.

b.        The skew is less than 30 degrees for steel beams.

c.        The deflection due to dead load of the adjacent span is less than 1 inch.

d.        There is no phased construction that requires the deck and abutment diaphragm to be placed together.

e.        The 1/2-inch joint for the preformed elastomeric compression joint seal between the deck and the approach slab is sawed as soon as possible for stress relief.

The final grade of the approach slab can then be established by using a string line.  One end of the string line should be secured at a distance of approximately 10 feet (3 meters) back on the deck and stretched over the proposed approach slab with the other end attached to a grade stake marked with the proposed pavement grade.  The final grade of the approach slab can then be determined.

Dimensions

The Contract plans will show the length of the approach slab.  All other details are dictated by Standard Drawing AS-1-81.  It will show the reinforcing and joint requirements as well as slab thickness and haunch details. 

Documentation Requirements - 526 Approach Slabs

1.        Length, width, and depth of forms.

2.        Porous backfill exposed at abutment.

3.        Number of bars and clearance maintained on reinforcing steel. Tied per 526.03.

4.        Dowel bars, if used.

5.        Surface finish.

6.        Grooved longitudinally to match deck grooving.

7.        Amount of curing compound used.

8.        Measure length and width for pay.

Type A Waterproofing applied to the face of the deck, backwall, or beams as shown in Bridge Standard Drawing AS-1-81 prior to placing concrete for the approach slab.

600 Incidentals

601 Slope and Channel Protection

Because of the straightforward nature of this item of work, no detailed explanation of the item is required in this manual.

602 Masonry 

Because of the straightforward nature of this item of work, no detailed explanation of the item is required in this manual.

605 Underdrains

Description (605.01)

The types of underdrains are specified in accordance with their application and intended usage.  For a brief description of typical applications, see Section 605.02.  If a more detailed description is required, see the ODOT Drainage Design Manual and the plans.

Materials (605.02)

Use approved granular material consisting of No. 8, 9, or 89 size Air-Cooled Blast Furnace slag, limestone, or gravel for underdrain backfill only, but not for underdrain outlet pipes.

Pipe for 605 Rock Cut Underdrains (605.02.A)

When the pay item description says Rock Cut Underdrains and the type of pipe is not specifically itemized in the Proposal, use one of the following:

1.        Corrugated Polyethylene Drainage Tubing (Perforated) 707.31.

2.        Polyvinyl Chloride Plastic Pipe 707.41.

3.        Polyvinyl Chloride Corrugated Smooth Interior Pipe (Perforated per 707.31) 707.42.

4.        Polyvinyl Chloride Solid Wall Pipe (Perforated per 707.31) 707.45.

Provide the pipe type on the 605 CA-P-2 Structure Underdrain Form.

Pipe for 605 Pipe Underdrains (605.02.B)

When the pay item description says Shallow Pipe Underdrains or Deep Pipe Underdrains, and the type of pipe is not specifically itemized in the Proposal, use one of the following:

1.        Perforated Concrete Pipe 706.06.

2.        Concrete Drain Pipe Extra Quality 706.07.

3.        Perforated Vitrified Clay Pipe 706.08.

4.        Clay Drain Tile Extra Quality 706.09.

5.        Corrugated Steel Underdrains, Type III 707.01.

6.        Corrugated Polyethylene Drainage Tubing (Perforated) 707.31.

7.        Polyvinyl Chloride Plastic Pipe 707.41.

8.        Corrugated Aluminum Alloy Pipe and Underdrains, Type III 707.21.

If the size and type of the underdrains required is a 6-inch (150 mm) Shallow Pipe Underdrain, and the type of pipe material is not specifically itemized, use 4-inch (100 mm) 707.31 Perforated Corrugated Polyethylene Drainage Tubing. An example would be 6-inch Shallow Pipe Underdrains listed in the description, and the Contractor can then furnish 4-inch 707.31 Underdrains placed at the same location as the 6-inch Shallow Pipe Underdrains. Provide the pipe type on the 605 CA-P-2 Structure Underdrain Form.

Pipe for 611 Conduit, Type F for Underdrain Outlets

The backfill requirements are as per 611. When the pay item description says, “611 Conduit, Type F for Underdrain Outlets,” and the type of pipe is not specifically itemized in the Proposal, use one of the following:

1.        Corrugated Polyethylene Smooth Lined Pipe 707.33.

2.        Polyvinyl chloride plastic pipe (non-perforated) 707.41.

3.        Polyvinyl chloride corrugated smooth interior pipe 707.41.

4.        Polyvinyl chloride solid wall pipe 707.45.

Provide the pipe type on the 605 CA-P-2 Structure Underdrain Form.

Pipe for 605 Construction Underdrains (605.02.C)

Corrugated polyethylene drainage tubing (perforated) 707.31 is the only pipe type permitted.

Provide the pipe type on the 605 CA-P-2 Structure Underdrain Form.

Pipe for 605 Prefabricated Edge Underdrains (605.02.D)

Prefabricated edge underdrains 712.10 is the only pipe type permitted.

Provide the pipe type on the 605 CA-P-2 Structure Underdrain Form.

Pipe Underdrains Construction (605.03)

Construct underdrains as follows:

Excavation (605.03.A)

Underdrain ID

6 inches (150mm)

4 inches (100mm)

Trench Width

14 inches (350mm)

10 inches (250mm)

Provide the trench width on the 605 CA-P-2 Structure Underdrain Form.

If filter fabric is specified, note this on the 605 CA-P-2 Structure Underdrain Form along with a sketch of how the fabric was placed and overlapped at the top of the trench.

Laying Underdrain (605.03.B)

Lay the underdrain true to line and grade with close fitting joints.  Use locking bands or smooth sleeve type couplers, which match the underdrain material type, to join 707.01, 707.31, 707.41, and 707.21.  When bell and spigot underdrain is used, lay it with the bell end facing up grade.  Set the underdrain on a solid bed shaped to fit the underdrain throughout its entire length.  Make all necessary connections with branches, wyes, tees, transitions, and bends that match the underdrain material type.  Close the upper ends of underdrains with suitable plugs.

Lay perforated underdrain so that the perforations are in the bottom half of the underdrain.

Provide the pipe joint type on the 605 CA-P-2 Structure Underdrain Form.

Backfilling (605.03.C)

Inspect the underdrains before placing any granular material.  Place the granular material for the full-width of the trench around the underdrain, and extend it to the bottom of the pavement or base as shown on the plans.  If underdrains are placed outside of the pavement or base area, extend the granular material to within 4 inches (100 mm) of the finished grade.  Fill the remaining depth of the trench with 203 embankment material. Provide the pipe backfill material type on the 605 CA-P-2 Structure Underdrain Form.

Protection (605.03.D)

Place the pavement over the underdrain trench within 90 days after placing the trench backfill.  If the trench remains open for longer than 90 days, remove and replace backfill contaminated by soil. Provide the dates when the underdrains were placed and the date the pavement was placed over the underdrain trench on the 605 CA-P-2 Structure Underdrain Form.

Construction Underdrains (605.04)

Excavation (605.04.A)

Construction Underdrain

4 inches (100mm)

Trench Width

10 inches (250mm)

Provide the trench width on the 605 CA-P-2 Structure Underdrain Form.

Trench Depth and Backfill (605.04.B)

Construct the trench depth to that shown on the plans or 30 inches (750 mm).  Backfill the full width and height of the trench with granular material. Provide the pipe backfill material type and trench depth on the 605 CA-P-2 Structure Underdrain Form.

Outlet (605.04.C)

Outlet the construction underdrains into the ditch or drainage structures.  There is no change in pipe types for the outlet. Provide the trench outlet location on the 605 CA-P-2 Structure Underdrain Form.

Removal (605.04.D)

Do not remove construction underdrains at any time.  If a construction practice requires the construction underdrains to be removed, then install replacements as soon as possible. For example, if trenching for a culvert would cut the construction underdrains.

Provide the dates when the construction underdrains were placed on the CA-P-2 605 Structure Underdrain Form.

Prefabricated Edge Underdrains (605.05)

Install the prefabricated edge underdrains against the outside wall of a 4 inch (100 mm) trench, and backfill the trench adjacent to the pavement with granular material.  Place the granular material in one or more lifts with a vibratory compactor run over the final lift to compact the granular material before placing the asphalt plug.  Place the first layer of granular material simultaneously with the trenching operation to hold the edge underdrains flush against the trench wall.

Before placing into the trench, splice the prefabricated edge underdrains, as required, using material furnished by the manufacturer and according to the manufacturer’s directions.  The manufacturer must furnish all material required for the splices and furnish any equipment required for splicing.  Construct splices to prevent adjoining sections of the prefabricated edge underdrain panels from separating. Provide the dates when the prefabricated edge underdrains were placed on the 605 CA-P-2 Structure Underdrain Form.

Underdrain Outlets (605.06)

Construct outlets per 611 and document this work as required in 611. The manufacturer must supply outlet fittings that transition between the underdrains and the outlet pipe. These are included in the 605 pay items. Place underdrains and outlets on fractured slab projects, such as crack and seat, rubblized, or break and seat projects before fracturing the existing pavement.

Mark all underdrain outlets with a wooden lath prior to final seeding.  Clean all debris from the outlets after final seeding. These are included in the 605 pay items.

Aggregate Drains (605.07)

Construct the aggregate drains after the completion of pavement.

Excavation (605.07.A)

Excavate trenches for aggregate drains to a minimum width of 12 inches (0.3 m) and to the depth shown on the plans.  Slope the bottom of the trench to drain and to keep it free from loose particles of soil.  Excavate the trench to provide a clean exposure of the granular pavement courses to be drained. Provide the dates of when the aggregate drains were placed on the 605 CA-P-2 Structure Underdrain Form along with a sketch.

Placing and Backfilling (605.07.B)

Use granular material for the drains.  Place the aggregate to a minimum depth of 8 inches (200 mm) above the bottom of the trench.  According to Item 203, backfill the remaining depth of the trench with suitable embankment material. Provide how the aggregate drains were backfilled on the 605 CA-P-2 Structure Underdrain Form.

Method of Measurement (605.08)

Provide the method used to measure the underdrains on the 605 CA-P-2 Structure Underdrain Form, e.g. station-to-station, by wheel, or other standard method of field measurement.

Basis of Payment (605.09)

Note the length paid per day. Provide this on the 605 CA-P-2 Structure Underdrain Form.

Documentation Requirements - 605 Underdrains

1.        Edge drains.

a.        Document on form CA-P-2.

b.        Trench backfilled with granular material, document type of aggregate.

c.        Measure as per 605.08.

d.        Provide precast reinforced concrete outlet per 605.06 as required.

2.        Aggregate drains.

a.        Width and depth of trench.

b.        Trench backfilled with granular material; document type of aggregate.

c.        Measure as per 605.08.

d.        Ends re-opened after final seeding.

606 Guardrail

Description (606.01) 

This work consists of constructing or reconstructing guardrail, guardrail posts, bridge terminal assemblies, end terminals, and impact attenuators, including the furnishing, assembling, and erecting of all component parts and materials.

Guardrail shall be deep beam rail Type 5, 5A, 8 or MGS.  Appurtenances shall include bridge terminal assemblies, end terminals, and impact attenuators.  Construction of the various types of guardrail include the furnishing, assembling, and erecting of all component parts and materials, complete in place at the location shown on the plans, or as directed, and according to the manufacturer’s recommendations where applicable.

Setting Posts (606.03) 

The posts shall be set or driven plumb in a manner that prevents battering or distorting of the posts.  The posts that are set or driven more than 1inch above grade shall be trimmed.  The trimmed posts shall be treated with a preservative material specified in 712.06. 

Erecting Rail Elements (606.04)

The plans shall show how to erect either a standard design (single-faced) guardrail or a barrier design (double-faced) guardrail.

Erect rail elements in a manner resulting in a smooth, continuous installation.  Shop-curved rail shall be used on curves with radii from 5 to 70 feet (1.5 to 22.4 m).  Do not allow straight elements to be bent or curved to fit a radius.

The bolts shall be tightened through expansion joints, as tight as possible, to prevent the rail elements from sliding past one another longitudinally.  Ensure that the bolts are long enough to extend at least 1/4 inch (6 mm) beyond the nuts.

Splice bolts that extend more than 1/2 inch (13 mm) beyond the nuts shall not be used.  For double-faced guardrail, the bolts shall extend from 1/4 inch to 1 inch (6 to 25 mm) beyond the nuts.

Do not allow burning or welding in the field.  The Engineer may approve making holes in the field, but only for special details in exceptional cases.  The Engineer may approve field punching, cutting, and drilling if the Contractor demonstrates that its methods do not damage the surrounding metal.

The galvanized surfaces shall be repaired that have been abraded such that the base metal is exposed, including threaded portions of all fittings and fasteners and cut ends of bolts as specified by ASTM A 780.

The guardrail shall be erected so that the bolts at expansion joints are located at the centers of the slotted holes.  The rail elements shall be lapped in the direction of traffic.  The plates at each splice shall make contact throughout the area of the splice.

Guardrail Rebuilt (606.05) 

Unless otherwise shown on the plans, the rebuilt guardrail shall be of the same type and spacing of members as the existing guardrail.

The following materials shall be new: posts, blockouts, bolts, washers, and incidental hardware, as necessary, to complete the guardrail, except:  (1) existing steel posts and blockouts that are not damaged and have a good galvanized coating may be reused, and (2) guardrail splice bolts that are undamaged and were not removed during salvage may be reused.

Impact Attenuators (606.06)

Before installation of the attenuator, all corresponding shop drawings, installation drawings, and instructions from the manufacturer shall be made available for the Engineer’s inspection.  Ensure the attenuator is installed as per manufacturer’s shop drawings.

The top of each foundation shall be graded at the same elevation as the adjacent travel lane and/or paved shoulder.  The anchors for the attenuator shall be adjusted to avoid pavement joints.

Method of Measurement (606.07) 

The Department will measure Guardrail, new or rebuilt, of the type specified, by the number of feet from center-to-center of end posts, excluding anchor assemblies.  If, however, end connections are made to masonry or steel structures, the Department will measure to the center of the normal post bolt slot.  If rail element is used across a bridge, the Department will measure to the first post off the bridge.

The Department will measure Anchor Assembly, of the type specified, by the number of each assembly furnished and erected complete.

The Department will measure Bridge Terminal Assembly, of the type specified, by the number of each assembly furnished and erected complete.

The Department will measure Impact Attenuator, of the type specified, by the number of each attenuator furnished and erected complete.

The Department will measure Guardrail Post, of the kind specified, by the number of each post furnished and erected complete.

Basis of Payment (606.08) 

The additional costs associated with furnishing and installing extra-length posts instead of standard-length guardrail posts are incidental to Guardrail Post, 8 foot (2.44 m) or Guardrail Post, 9 foot (2.75 m).

For the extra costs associated with furnishing and installing extra-length posts in lieu of standard-length guardrail posts, payment for 9 foot (2.75 m) guardrail posts is considered full compensation.

Documentation Requirements

Use Form CA-D-3A to document the following items:

1.        Depth post driven, post spacing.

2.        All cuts and abrasions on wood post treated with application of approved preservative.

3.        Rail erected accurately to line and grade, all hardware drawn tight.

4.        Anchor assemblies and bridge terminal assemblies.

a.        Number, diameter, and depth of holes drilled.

b.        Top 4 inches (10 cm) of concrete anchor formed.

c.        Diameter, length, and number of anchor bolts placed.

d.        Number, spacing, size, and clearance maintained on reinforcing steel.

e.        Top cured.

f.         Measure and pay as per 606.07.

607 Fence

Clearing and Grading (607.03)

Clearing and grading shall be performed to construct the fence to the required alignment and to provide a reasonably smooth ground profile at the fence line. The contractor shall perform 607 Fenceline Seeding and Mulching according to Item 659 Seeding and Mulching on all areas disturbed by the clearing and grading for the fence within 8 months of the activity.  The Department will deduct the area paid for under Item 607 Fenceline Seedng and Mulching from Item 659 Seeding and Mulching quantities as described in the plan, if applicable.

Post Assemblies (607.04)

During the curing period of the concrete encasement, the brace end, corner, gate, and pull or intermediate anchor posts shall be secured in final position.  Do not require forms for post encasement.

For Type 47 and Type CLT fence, the maximum spacing between intermediate anchor post assemblies, or between end post assemblies and intermediate anchor post assemblies, are 660 feet (200 m).

Horizontal Deflection (607.05)

At points of horizontal deflection, the fence shall be constructed as follows:

1.        Type 47 Fence.  If the fence changes alignment by more than 1 degree, but not more than 4 degrees, either steel line posts encased in concrete, or wood posts without encasement, shall be installed at all horizontal deflection points.  If the change in alignment is more than 4 degrees and less than 30 degrees, an intermediate anchor post assembly shall be installed at the deflection point.  If the change in alignment is 30 degrees or more, a corner post assembly shall be installed at the deflection point.

2.        Type CLT Fence.  If the fence changes alignment by more than 1 degree, but not more than 4 degrees, line posts encased in concrete shall be installed at all horizontal deflection points.  If the change in alignment exceeds 5 degrees, a post brace and truss rod in each fence panel adjacent to the post located shall be installed at the angle point.  If the change in alignment exceeds 5 degrees, the footings for all posts located at deflection points shall be constructed as specified for end posts.

Line Posts (607.06)

Line posts shall be set according to the following:

1.        Type 47 Fence.  The spacing of line posts is not to exceed 12 foot (3.6 m) intervals.  Line posts at the bottom of dips or depressions in the ground surface are to be anchored in concrete. 

2.        On tangents, line posts shall be placed so that the fabric, when installed on the side toward the highway, is 2 feet (0.6 m) from the Right-of-Way line.  If adjacent to Right-of-Way lines with less than 5,740 feet (1750 m) radius (in excess of 1 degree curvature), line posts shall be constructed on chords so that the fabric, when installed on the side toward the highway, is not less than 2 feet (0.6 m) or more than 8 feet (2.4 m) from the Right-of-Way line.

3.        Type CLT Fence.  The tops of driven line posts shall be protected by drive caps or other method to prevent distortion of the exposed end.  Line posts are to be spaced at no more than 10 foot (3 m) centers, and placed so that, when the wire is fastened on the side toward the highway, it is 1 foot (0.3 m) from the Right-of-Way line.

Fabric (607.07)

The fabric shall not be erected until after 5 days from the time of setting the posts, when using regular cement, or until after 3 days, when using high early strength cement.

Type 47 fabric shall be stretched and fastened to line posts using galvanized ties.  At a minimum, one tie shall be used for each of the top and bottom horizontal wires and one tie for each alternate horizontal wire below the top horizontal wire.

Chain-link fabric shall be fastened to the line posts using clips or bands spaced approximately 14 inches (0.4 m) apart, and to the  top tension wire using bands or tie wires at approximately 24-inch (0.6 m) intervals or less.  Successive rolls of fabric shall be joined by weaving a single picket into the ends of the rolls to form a continuous mesh.

Method of Measurement (607.09)

The Department will measure Fence, Type ___ by the number of feet (meters), complete in place.  The Department will measure along the top of the fence from outside-to-outside of end posts, exclusive of gates and other openings.

The Department will count Gate, Type ___ by the number of complete units of the size and type specified.

Documentation Requirements - 607 Fence

1.        Distance between line posts.

2.        Depth line posts driven.

3.        Diameter and depth of concrete used to encase post placed in dip section, fence not attached to post for minimum 5 day cure, and 3 days for high early.     

4.        Post for end, corner, gate, pull, and intermediate anchor assemblies driven to a depth of __________  (If not driven to grade, diameter and depth drilled for encasement).

5.        Fabric clipped to post at top wire, bottom wire, and alternate wires between.

6.        Document location and measure as per 607.09.

7.        Document Fenceline Seeding and Mulching locations and quantities of area seeded. Deduct Fenceline Seeding and Mulching from 659 Seeding and Mulching if applicable

608 Walks, Curb Ramps, and Steps

Description (608.01)

This work consists of constructing walks, curb ramps, and steps.

Concrete Walks (608.03)

Subgrade should be prepared and compacted to the elevations and locations as shown on the plans. Forms should be checked for any bulges and for proper cross slope.  Ensure subgrade is wetted prior to placement of concrete for walk. Do not allow concrete finishers to apply water to the surface of pavement to aid in finishing of concrete. Any additional water added to the surface of the fresh concrete increases the water/cement ratio of mortar and adversely affects air content. This results in a less durable matrix and the concrete surface is more prone to early scaling and general surface deterioration. Prior to acceptance the walk should be checked again for cross-slope, surface defects, cracking outside of joints.

Curb Ramps (608.07)

The same practices outlined above for Concrete Walks should apply to curb ramps. Additional attention should be given to this operation to ensure that the ramps conform to the slopes, elevations and dimensions given in the plans and applicable standard drawings. It is critical to ensure that minimum dimensions are adhered to and that slope tolerances are not exceeded to ensure compliance with ADA standards.

Method of Measurement (608.08)

Concrete Walk, Asphalt Concrete Walk, Aggregate Walk, Curb Ramp, and Detectable Warning are to be paid by the number of square feet of finished surface complete in place. Concrete Steps are to be paid by the lineal foot. Measure the completed in place length of each tread width, along the front edge, and add together for the total length.

Documentation Requirements - 608 Walks, Curb Ramps, and Steps

1.        Sidewalks.

a.        Concrete walks.

i.         Depth and width of base material (if required).

ii.        Wet subgrade (if necessary) and compact.

iii.      Slip formed or fixed form construction.

iv.      Were forms oiled?

v.        Depth of concrete.

vi.      Concrete used.

vii.     Spacing on joints – 5 foot (1.5 m) intervals.

viii.   Surface texture.

ix.      Curing (required and used).

x.        Expansion material was placed at full-depth at ______________(location).

xi.      Slope = ________(inches/ft [cm/m] cross-slope).

xii.     Measure length and width and pay in square feet.

b.        Asphalt concrete walks.

i.         Depth and width of base material.

ii.        Compaction of base material.

iii.      Form check, depth, and width.

iv.      Asphalt used and compaction.

v.        Slope = ________(inches/ft [cm/m] cross-slope).

vi.      Measure length and width and pay in square feet.

c.        Crushed aggregate walks.

i.         Form check, depth, and width.

ii.        Crushed aggregate used.

iii.      Compaction.

iv.      Measure length and width and pay in square feet.

2.        Steps.

a.        Form dimensions (riser and tread).

b.        Reinforcing steel (if required), number, and size of bars/clearances.

c.        Were forms oiled?

d.        Concrete used.

e.        Curing (required and used).

f.         Surface finish.

g.        Measure length of each tread and then add together for pay.

3.        Curb ramps.

a.        Form dimensions.

b.        Concrete used.

c.        Curing (required and used).

d.        Surface finish.

e.        Measure and pay by the square foot (square meter).

609 Curbing, Concrete Medians, and Traffic Islands

Documentation Requirements - 609 Curbing, Concrete Medians, and Traffic Islands

1.        Stone curb.

a.        Stone type.

b.        Sizing of cut pieces.

c.        Straight edge on top and exposed face?

d.        Ends dressed at right angles?

e.        Edge at gutter cut to spec?

f.         Subgrade compaction.

g.        Granular base (if required)

h.        Batter set correctly?

i.         Construction of curb joints.

j.         Measure length for pay and document location. (Station and plan location).

2.        Cast-in-place concrete curb and combination curb and gutter.

a.        Form dimensions or slip form (if slip formed, measure finished curb dimensions).

b.        Form line and grade or if slip form validate finished curb line and grade.

c.        Steel forms used?

d.        Forms oiled?

e.        Subgrade compacted and wetted.

f.         Concrete JMF.

g.        Concrete placement.

h.        Tie bars placed (if required).

i.         Joint spacing.

j.         Joint dimensions.

k.        Joints sawed or formed by metal plates.

l.         Finishing.

m.      Curing (required according to 451 and used).

n.        Measure length for pay and document location. (Station and plan location).

3.        Asphalt concrete curb.

a.        Tack coat application rate.

b.        Asphalt Concrete JMF

c.        Placement Method A or Method B used?

d.        Measure length for pay and document location. (Station and plan location).

4.        Concrete median and traffic island.

a.        Concrete JMF

b.        Form dimensions or slip form (if slip formed, measure finished dimensions).

c.        Steel forms used?

d.        Forms oiled?

e.        Subgrade compacted and wetted.

f.         Joint spacing.

g.        Joint dimensions.

h.        Joints sawed or formed by metal plates.

i.         Finishing.

j.         Curing (required and used).

k.        Measure and calculate square yards for payment.

610 Cellular Retaining Walls

This specification covers general types of retaining walls.  The first are walls made up of layered and tiered precast reinforced blocks.  The second are constructed with metal columns and front and rear metal filler panels.  Both of these wall types are specialized and require Director’s approval.  Acceptable manufacturers are sometimes indicated in the plan notes. 

Documentation Requirements - 610 Cellular Retaining Walls

1.        Director’s approval is required.

2.        Manufacturer’s wall type must be in successful commercial use for a period of at least 3 years.

3.        For galvanized metal walls, the Contractor must furnish 3 copies of the Manufacturer’s, “Analysis and Coating Test Certificate.”

4.        State type size and quantity of units.

5.        Precast concrete units must be produced by a certified precast concrete producer and shipped with a TE-24.

6.        Type of backfill used and how compacted.

7.        Measure and pay as per 610.08 and 610.09 of the C&MS.

611 Pipe Culverts, Sewers, Drains, and Drainage Structures

Description (611.01)

This specification states requirements in terms of the required results and includes criteria for verifying compliance without stating the methods for achieving the required results.  The types of pipe are specified in accordance with their application and intended usage.  For a brief description of typical applications, refer to “Materials,” Section 611.02.  For a more detailed description, refer to the Location Design Manual, Volume 2, Drainage Design, and the plans.

The Inspector will monitor the materials and the installation plan. The Contractor will install the materials as well as monitor and document the installation while providing third party inspection/evaluation and certification of performance based on contract criteria.

Materials (611.02)

Materials selected as part of the installation plan will be inspected and approved by the Inspector prior to use.

Type A Conduits

Type A conduits are sealed culvert cross drains under pavements, paved shoulders, and embankments. These culvert cross drains are used to convey water from one side of the roadway to the other.  These culverts can be either smooth lined or corrugated.  Type A conduits are under pavement and open at both ends.

Type B Conduits

Type B conduits are storm sewers under pavement, paved shoulders, and commercial or industrial drives.  Storm sewers are used to convey water from one manhole or catch basin to the other. Storm sewers are always smooth lined.  Type B conduits have one or both ends closed with a drainage structure.

Type C Conduits

Type C conduits are storm sewers which are not under pavement, paved shoulders, or commercial and industrial drives.  Like Type B conduits, these conduits are connected to a manhole or catch basin and are always smooth lined.  Type C conduits have one or both ends closed with a drainage structure.

Type D Conduits

Type D conduits are culverts placed under residential driveways or bikeways. These conduits can be either smooth lined or corrugated. 

Type E Conduits

Type E conduits are farm drain headers in or outside the right-of-way or used for ditch elimination beyond the paved shoulder. These conduits can be either smooth lined or corrugated. 

Type F Conduits

Type F conduits are other miscellaneous pipe where a butt joint or a short length jointed pipe would be undesirable.  Outlets for underdrain or farm drains, house drain connections, pull box drains, or steep portions of a median outlet under an embankment are examples of Type F applications. These conduits can be either smooth lined or corrugated. 

Bedding and Backfill

The materials used for bedding and backfill are approved prior to use.  Installation will be in accordance with the Contractors accepted installation plan.

Low Strength Mortar Backfill (LSM)

In some cases, the plans designate the use of LSM as bedding and/or backfill material.  The requirements for LSM can be found in C&MS 613. There are three Types of mixes. Type 1 is a mixture of cement, fly ash, sand, and water.  The Type 2 mixture substitutes an entrained air additive for the fly ash. The Type 3 mixture is a mixture of fly ash and water. All three mixes may be used, or an alternative mix, submitted for approval by the Contractor, may be used if the plans do not call out a mix. The alternate mixes shall meet the criteria in C&MS 613.  Changes in the material type, amount, or sand gradation are allowed, as long as the final mix has the required strength, fills the voids, and sets up.

Submittals (611.04)

Shop Drawings and Calculations

The Project personnel will ensure Shop Drawings and calculations are sealed by a Registered Engineer as well as checked and properly sealed by a second Registered Engineer.

The Project personnel will ensure Load Rating calculations are submitted to the Office of Structural Engineering and a copy is filed in the project records.

The Project personnel will ensure Shop Drawings and calculations for Reinforced Concrete Circular Pipe, which require a special design, are submitted to the Office of Structural Engineering and a copy is filed in the project records.

The Project personnel will ensure Shop Drawings and calculations for Precast Reinforced Concrete three-sided flat topped culverts, precast reinforced concrete arch culverts, or precast reinforced concrete round sections, (706.051, 706.052, or 706.053) are submitted to the Office of Structural Engineering, and a copy is filed in the project records.

The Project personnel will ensure that if the Contractor substitutes one structure for another, they also submit hydraulic calculations to the Office of Hydraulic Engineering.

Installation Plan

Each size and type of conduit (A, B, C, D, E, F, etc.) to be installed will require a written installation plan along with written confirmation from the conduit manufacturer. Project personnel will review and accept the installation plan if it includes all the requirements listed in 611.04.B:

1.     Trench and excavation cross-sections with dimensions.

2.     Locations where the conduit is installed in a cut situation and where it is installed in a fill situation.

3.     Type of bedding and backfill material used and maximum lift thickness.

4.     Compaction density requirements for bedding and backfill and compaction equipment.

5.     Identify the starting location (outlet or inlet) for each run of conduit. All conduit must be laid from the outlet to the inlet unless approved by the Engineer.  Bell or groove-end Type A conduit must have a bell or groove-end at the inlet.

6.     Maximum allowable joint gap between conduit sections.

7.     Other installation details, as necessary.

8.     Written confirmation from the conduit manufacturer that the pipe material and strength supplied are appropriate for the material and density requirements described in the installation plan for the backfill and bedding as well as the height of cover. Ensure the pipe material meets the durability design specified in the plans.  This confirmation by the conduit manufacturer will not relieve the Contractor of the responsibility for obtaining the required results.

The Project personnel will monitor the installation process to ensure compliance with the installation plan.  Each installation plan should be filed in the project records in the appropriate reference file.

For further detail on the Material Certification Program, contact the District Testing Engineer or refer to Materials Management Sampling and Testing Program Manual.

Construction Inspection

Each day the Contractor will submit to the Project personnel a properly completed construction inspection form, CA-P-1, for conduit and form, CA-P-3, for drainage structures.  The project personnel will review the forms to ensure the information on the construction inspection form is complete and accurate. The forms should document the installation procedure described in the accepted installation plan. 

The forms should include trench and bedding measurements every 50 feet with a minimum of two per run.  Measurements should be recorded to the nearest 0.1 foot (30 mm). 

All items regarding the conduits and drainage structure should be included on the daily inspection reports, including:

1.     Pipe joint sealer application.

2.     Coupling band installation.

3.     Field paving of conduits, materials, and installation process.

4.     Concrete curing applied.

5.     Waterproofing materials and installation process.

Performance Report

The Performance Report will consist of a performance inspection, a performance survey, a surface settlement evaluation, and an independent evaluation.

The Project personnel will witness the performance inspection, as performed by the Contractor. The conduits and structures should be cleaned of all debris to allow for proper inspection. The performance inspection should be 30 days after all cover up to the final grade or aggregate base has been completed, but should be completed before any pavement is placed. 

A performance inspection report will be created for each conduit size (greater than or equal to 12 inches) and material type. The report will include the following information:

1.     Project number and County-Route-Section.

2.     Date of performance inspection.

3.     Type and size of conduit.

4.     Conduit diameter report from the manufacturer.

5.     Time of video recording.

6.     Location (e.g., station and offset) and viewing direction.  For Type A and B conduit, include the latitude and longitude of the conduit at the location where the culvert centerline and the roadway centerline intersect. Ensure the units are in decimal degrees to the sixth decimal place. Use a Global Navigation Satellite System (GNSS) unit that is accurate to within 15 feet (4.5 meters).

7.     Summary of all defects, including type, measurement, and location.

8.     For remote inspections using a mandrel, indicate in the performance report, the size of the mandrel and how it was calculated.  Document all locations where the mandrel was unable to advance through the conduit.

9.     For remote inspections using a crawler mounted camera with laser profiler, include:

        a.     Three dimensional model of the conduit based on the laser profile         measurements.

        b.     Digital profile of conduit extracted from the inspection video.

        c.     Calculations of the ovality, capacity, and delta of the conduit.

        d.     Explanation as to why data was unattainable for any section of the        conduit.

Figure 611.A – Internal Conduit

(a) Defective and open joint – VC pipe, (b) Defective connection – VC pipe, (c) Perfect connection – VC pipe, and (d) Exposed reinforcement – RC pipe.

Figure 611.B – You Never Know What you Will Find

Figure 611.C – Sample Pipe Inspection Report including Ovality Observations

Figure 611.D – Example Mandrel Gauges

A performance survey will document the elevations and locations of each Type A, B, and C conduit and drainage structure to determine conformity with the Contract Documents (Plans). 

An evaluation of surface settlements within 4 feet of the trench limits or drainage structure will be created by an independent registered engineer and submitted to the Project personnel.

After the performance inspection, a survey and settlement evaluation is completed, and an independent registered engineer will provide a review of the conduits and structures. This independent registered engineer will provide a statement indicating that no repairs are required, or that repairs are required, and the repair plan meets the design requirements.

Documentation Requirements - 611 Pipe Culverts, Sewers, Drains and Drainage Structures

1.     File the Contractor supplied Shop Drawings with each applicable reference.

2.     File the Contractor supplied Installation Plan in the project records with each applicable reference.

3.     File Contractor supplied form CA-P-1 or CA-P-3 as appropriate in the project records with each applicable reference.  Make sure all waterproofing and field paving is noted in the comments section of the forms.

4.     Enter the daily amounts installed into SiteManager as appropriate.

5.     File the Contractor supplied Performance Inspection, Performance Survey, and Surface Settlement Evaluation in the project records with each applicable reference.

6.     File the Conduit Evaluation and Drainage Structure Evaluation as provided by an independent registered engineer in the project records with each appropriate reference.

613 Low Strength Mortar Backfill

Documentation Requirements - 613 Low Strength Mortar Backfill

This section recommends minimum documentation and critical inspection requirements for Item 613.  The following documentation requirements must be recorded in the appropriate sections of the CA-P-1 Pipe Construction Form and in the project daily reports.  Specifications or other requirements waived by the Project Engineer shall be noted in the daily diaries.

1.        Record on the CA-P-1 form how the pipe was anchored to prevent it from floating in the trench.

2.        Record how the LSM was brought up in the trench. Indicate if the LSM was brought up on both sides of the pipe evenly.

3.        Indicate if forms or embankment was placed at ends of pipe to prevent the LSM from flowing into the ditch.

4.        Record if the LSM was brought up to grade line as specified in plans.

5.        A comparison needs to be made between the quantity installed and the quantity computed from the plans (take-off quantity).  Record both the installed and take-off quantity on the CA-P-1 form. Measure and pay the computed amount of cubic yards (cubic meters) unless it is determined by the Engineer that the amount used is reasonable for pay. Documentation of the take-off and installed quantities is an important part of the record, particularly when paying less than the quantity delivered.

614 Maintaining Traffic

Description (614.01)

This work consists of maintaining and protecting vehicular and pedestrian traffic according to these provisions.  For through traffic, the Special Provisions or the plans will designate whether the highway will be closed with detours, roads, and run-arounds provided or whether traffic will be maintained through all or portions of the project.

Traffic Facilities (614.02)

Vehicular and pedestrian ingress and egress for all property adjacent to any improvement shall be provided at all times. 

Contractor maintenance responsibilities, including pothole patching, begins for a section of highway when the Contractor begins the work in that section and ends with the acceptance of the work under 109.11 or 109.12.  The two directions of a divided highway are considered separate highway sections and the start of work on one direction does not begin maintenance responsibilities on the other direction.

Traffic Control General (614.03)

The traffic control shall conform to the requirements of the plan, standard construction drawings shown on the plans, and the OMUTCD for Streets and Highways, hereinafter called the Ohio Manual, for the installation, maintenance, and operation of all traffic controls and traffic control devices.  When the plans or standard construction drawings do not cover a specific traffic control situation, the necessary traffic control devices shall be placed according to the Ohio Manual and procedures required by the Ohio Manual shall be implemented.

The OMUTCD (Ohio Manual on Uniform Traffic Control Devices) has three levels of compliance to indicate the type of standard and whether it is mandatory, recommended, or optional:

·         All mandatory conditions are listed under the section heading “Standard.”

·         All recommended conditions are listed under the section heading “Guideline.”

·         All allowed conditions are listed under the section heading “Option.”

·         A fourth grouping, “Support,” was added to include statements that were not mandatory, recommended, or optional, but rather general information.

Supplement 1061 prequalifies the portable changeable message boards.  Only two panel of information shall be allowed.

Drums, signs, sign supports, barricades, impact attenuators, and other traffic control devices that are certified to meet NCHRP 350 safe-crash standards, or as modified by Contract Documents, shall be used.  Do not allow heavy, non-yielding devices or supports that do not conform to the current standards of NCHRP 350, unless allowed by Contract Documents.

Ensure the drums are furnished with Type G, reboundable reflective sheeting, which complies with the requirements of 730.191.  Ensure that owner identification markings on construction drums are no more than 1 inch (25 mm) in character height and are located at least 2 inches (50 mm) below the reflectorized bands or on the top or bottom horizontal surfaces of the drum.  Ensure the drums are ballasted according to the manufacturer’s recommendations.

If equipment, vehicles, and material are stored or parked on highway rights-of-way, they shall be located no less than 6 feet (2 m) behind existing guardrails or no less than 30 feet (9 m) beyond the traveled way, unless otherwise permitted by the Engineer.  At night, if any such material or equipment is stored between the side ditches or between lines 6 feet (2 m) behind any raised curb, they shall be clearly outlined with dependable lighted devices that are approved by the Engineer.

Flaggers (614.08)

Whenever one-way traffic is established, at least two flaggers shall be used, unless the Engineer authorizes otherwise, and signs, cones, barricades, and other traffic control devices shall be erected according to the Ohio Manual.  Flaggers shall maintain positive and quick means of communication at the opposite ends of the restricted area.

Asphalt Concrete for Maintaining Traffic (614.13)

The Contractor may use either a Type 1 or Type 2 mix of Item 448 asphalt concrete PG 64-22, or an asphalt concrete surface course the Engineer approves.  Surface course materials shall be placed where the Engineer directs for maintenance of the existing pavement, shoulders, or structures.

Where materials are placed in small quantities or under adverse conditions, the Engineer may waive specification requirements for placing and finishing if, in the judgment of the Engineer, it is determined that the Contractor can obtain satisfactory results in providing a smooth and durable pavement surface.

Performance (614.14) 

If, in the opinion of the Engineer, the Contractor is not furnishing proper maintenance of traffic facilities and proper provisions for traffic control, the Department may take the necessary steps to place them in proper condition. The Department will deduct the cost of such services from any money that may be due or become due the Contractor.

Method of Measurement (614.15)

The Department will measure Work Zone Marking Signs as the number of sign installations, including the sign, necessary supports, and all attachment hardware.  The Department will include all other work zone signs under Maintaining Traffic unless separately itemized.

The Department will measure Work Zone Pavement Markings complete in place, by class and material, in the units designated.

The Department will measure line quantities as the length of the completed stripe, including gaps, intersections, and other sections of pavement not normally marked.

Basis of Payment (614.16) 

Unless separately itemized, the lump sum price bid for Maintaining Traffic shall include the cost of removing conflicting pavement markings and layout, application and removal of pavement markings, maintaining the existing highway in a safe condition for public use, and removing abrasive and salt residue remaining from snow and ice control performed by the Department or local governments. The lump sum price bid for Maintaining Traffic shall also include the cost of providing flaggers and their equipment, while maintaining the equipment in an acceptable condition, and subsequently removing the following work zone traffic control items, as required by the Contract Documents:

1.        Signs, supports, and warning lights.

2.        Drums, cones, gates, barricades, and vertical panels.

3.        Flashing arrow panels.

4.        Work zone traffic signals.

5.        Lighting for work zone signals and flaggers.

If traffic permanently damages beyond use, any of the following items, the Department will compensate the Contractor for the fair market value of the damaged item according to 109.05, provided the Contractor has pursued, but failed to obtain compensation from the motorist.  Follow the procedures given in 107.15 for traffic damage compensation to completed permanent items of work. Obtain compensation from the motorist before requesting compensation from the Department.

1.        Flashing arrow panel.

2.        Work zone signal, pole, or controller.

3.        Lighting unit or pole.

4.        Changeable message sign.

5.        Work Zone Impact Attenuator.

The lump sum price bid for Detour Signing includes the cost of the Contractor furnishing, installing, maintaining, and removing the detour signing shown on the plans and their necessary supports.

The Department will pay for the following items under their associated item numbers: 502, “Bridges”; 615, “Roads and Pavement”; 622, “Portable Concrete Barrier.”  The Department will pay for aggregate and calcium chloride authorized by the Engineer and used for Maintaining Traffic under Items 410 and 616.

Documentation Requirement – 614 Maintaining Traffic

ODOT Long Term Inspection Form

Use the ODOT Long Term Inspection form (CA-D-8) for long-term projects that are under temporary traffic control twenty-four hours a day, seven days a week.  Below are the guidelines of how and when to fill out the form.

Purpose of form:  To document the condition of the work zone traffic control.

When to review: 

·         At the beginning of each project.

·         Immediately following a change to the work zone traffic control (construction phase change).

·         Review weekly through the duration of the project.  It is suggested that the review be performed on the morning of the day prior to the last work day for the week.   (Example:  If the project normally works Monday through Friday, then perform the review on Thursday morning; if the project normally works Monday through Thursday, then perform the review on Wednesday morning.)

·         All inspections are to include a nighttime review (preferably twice a month).

·         Following receipt of information regarding a reported crash.

Who uses the form: 

·         ODOT Project personnel – in accordance with the inspection schedule.

·         Contractor personnel – if a Worksite Traffic Control Supervisor is specified in the Contract Documents, the review is to be performed and documented on a daily basis.

·         ODOT District Work Zone Traffic Manager – in conjunction with routine program responsibilities.

·         ODOT County Managers – to document permit or ODOT maintenance work zones.

General

ODOT Project No.

Self-explanatory; record all information accordingly. 

Contractor

Fill in the name of the Contractor who is in charge of the zone.

Date

Fill in the date of when the zone was inspected. 

Time and A.M./P.M.

Fill in the time of the review.

Weather

This information in important since weather and ambient lighting conditions affect the visibility of pavement markings and signs. Circle or fill in the weather conditions.

Visibility

Describe any issues with visibility.

Received By

Indicate the ODOT Inspector/Engineer who received the inspection form or performed the inspection if no WTS is specified in the Contract Documents.

Date

List the date the ODOT Inspector received the form from the WTS or the date the Inspector performed the review.

Section A:  “Drive Through”

Drive through the work zone at the posted speed and take note of the traffic’s movement and its reaction to traffic control devices.   Space for additional comments and/or recommendations is provided at the bottom of page two.

1.  “Work zone free of difficult or unexpected maneuvers?”

Based on the drive through and observation of the traffic, make a determination of the adequacy of the overall work zone traffic control.  If problems are observed, check the box and record the observed problem in the comments section.

2.  “Adequate warning of conditions?”

Do the signs provide adequate reaction time?  If no, check the box and record the observed problem in the comments section.

3.  “Is signing clear/uncluttered and properly spaced?”

Are the warning signs visible and easy to read and understand?  If no, check the box and record the observed problem in the comments section.

4.  “Are traffic control devices sufficiently visible?”

Are all the traffic control devices (signs, cones, plastic drums, tubular markers, arrow panels, etc.) visible?  If no, check the box and record the observed problem in the comments section.

5.   “Is project free of traffic accidents?”

Are all accidents, if any, being documented and reported to the Project Engineer?

6.   “Are equipment/materials properly stored off roadway?”

Is equipment and materials properly stored according to specification?

7.  “Are congestion points absent from within project limits?”

Did you observe any congestion or delay (as defined by the policy)?  If so, check the box and record the observed problem in the comments section.

8.   “Do work vehicles properly interact with traffic?”

Do work vehicles enter and leave the work zone without causing any confusion to the travelling public?

Section B:  “Signs and Lights”

1.  “Are signs and lights working properly and visible?”

Are all of the signs and lights visible and appropriate? 

2.  “Are all permanent and temporary signs consistent with one another?”

3.  “Proper size?”

Are signs and fonts the proper size as per Contract Documents?

Section C:  “Portable Changeable Message Signs and Arrow Panel”

1. “Application Meet Guidelines?”               

Does the message on the PCMS give conflicting information or guidance?  Note the message in the comments section.  If there is more than one PCMS on the project, also note the location.

2.  “Correct Placement?”              

Based on your observations made during the drive through (Section A), was the PCMS/Arrow panel correctly located or necessary?   Include your recommendation for the correct location or need.

3.  “Delineated with No Cones/Drums?”     

Is the PCMS/Arrow panel delineation with cones/drums?

4.  “Dimmed at Night?”

Is the PCMS is dimmed at night?

5. “Are all boards and signs working properly (bulbs correctly aligned, no bulbs out, etc.).”

Self-explanatory.

Section D:  “Drums/Barricades/PCB/Impact Attenuators

1. “Taper length acceptable?”

Refer to Chapter 6, Section 6C.08 of the OMUTCD.  Check the box if the taper length is too short for the conditions (speed and lane width).  If not acceptable, note the location, deficiency, and recommendation in the comments section.

2. “Spacing acceptable?”

Refer to Chapter 6, Section 6F.55 of the OMUTCD. When using 42-inch reflectorized cones at night, the spacing between devices shall be 40 feet in the tangent section (the cones should not be used in the taper). Based on your observations made during the drive through (Section A), check the box applicable to that device if the space between devices exceeds the maximum length based on the conditions (speed).  Note the location and recommendation in the comments section.

3.  “Properly aligned/cleaned/secured?”

Based on your observations made during the drive through (Section A), check the box if the drums, cones, or tubular markers are out of alignment in either the transition or tangent areas.  Note the location and recommendations in the comments section.

4.  “Adequate number of devices?”

Based on your observations made during the drive through (Section A), if hazards are not adequately protected or delineated, check the box under the letter heading for that device.  Note the location and recommendations in the comments section.

5.  “Object markers/barrier reflectors in place and visible?”

Based on your observations made during the drive through (Section A), are the markers and reflectors performing as intended?

6.  “Attenuators in place?”

Based on your observations made during the drive through (Section A), are the attenuators placed in the appropriate locations?

7.  “Attenuators secured and in good condition?” 

Based on your observations made during the drive through (Section A), are the attenuators placed according to Contract Documents and free from damage?

Section E:  “Pavement Markings and Raised Pavement Markers (RPMs)”

1.  “Are pavement markings visible and in good condition?”

Self-explanatory.

2.  “Is striping free of conflict?”

Based on your observations made during the drive through (Section A), check the appropriate box if any conflicts are observed between the permanent and temporary pavement markings, which could cause driver confusion.  Note the location(s) in the comments section.

3. “RPM's in good condition, proper number, and correspond to pavement markings?”

Based on your observations made during the drive through (Section A), check the box if additional raised pavement markers are needed to provide positive guidance to the motorists.  Note the location(s) in the comments section.

Based on your observations made during the drive through (Section A), check the box if either existing or temporary raised pavement markers, which do not correspond to the current pavement markings, are observed.  Note the location(s) in the comments section.

Additional General Information

Videos/photos of work zone:

Mark the box for documentation purposes and list the photographer.

Corrective action needed:

Note if any corrective action is needed in the comments section

Describe traffic accidents (if any):

Self-explanatory.

Damaged or missing MOT items:

Document missing or damaged MOT items that were witnessed during the review.

Lane closures/rolling road blocks:

Document any lane closures and/or rolling road blocks that occurred during the review.

LEO’s:

Document the number of LEO’s, the total hours the LEO’s were present, and what their activities were.

Inspected by:

Ensure that the form is signed and dated by the Contractor’s worksite traffic supervisor as specified in the Contract Documents.

ODOT Short Term Inspection Form

The ODOT Short-Term form (CA-D-7) is for projects that are typically set up and torn down daily.  Below are the guidelines of how and when to fill out the form.

For projects where the MOT is set up new each day, such as mill and fill operation, form CA-D-7 (Short Term Work Zone Review) should be completed daily with each new set-up (maintenance, utility, permit, and daily contract operations).

General

County/Route/Section/Project No.: Record all information accordingly

 Date: Fill in the correct date.

Time and A.M./P.M.: Fill in the time of the review. Circle A.M. or P.M.

Weather Conditions: Fill in the weather conditions.

Type of operation or traffic control:

Circle the type of operation or traffic control that is being performed at the time of the review.

Use "Other" to document situations not described.

Who is completing the work?

Document who is working on the roadway, in the case of a contractor or utility, include the company name.

Traffic control and safety devices

This section is used to describe the effectiveness of the traffic control devices, including signs, flagger, cones, drums, arrow boards, signals, PCMS, etc. Drive through the work zone at the posted speed and take note of the traffic's movements and reactions to the traffic control devices.

Condition

This section is used to describe any inadequacies or deficiencies with the Condition of the Traffic Control and Safety Devices. If no inadequacies or deficiencies are noted, check "None" and continue to Placement. If Conditions are not adequate, record the deficiencies, as well as the corrective action to be taken.  When deficiencies have been corrected, record the date.  Examples of items to review:

1.        Are the traffic control devices legible?

2.        Are they clean and reflective?

3.        Do any of them need to be replaced?

4.        Are any non-standard?

5.        Are they the correct size?

Placement

This section is used to describe any inadequacies or deficiencies with the Placement of the Traffic Control and Safety Devices. If no inadequacies or deficiencies are noted, check "None" and continue to Visibility. If Placement is inadequate, record the deficiencies, as well as the corrective action to be taken.  When deficiencies are corrected, record the date.  Examples of items to review:

1.        Are the traffic control devices appropriate?

2.        Do they provide adequate reaction time?

3.        Are any of the messages conflicting?

4.        Are the maneuvers difficult or unexpected?

Visibility

This section is used to describe any inadequacies or deficiencies with the Visibility of the Traffic Control and Safety Devices. If no inadequacies or deficiencies are noted, check "None" and continue to Flagger. If Visibility is not adequate, record deficiencies, as well as the corrective action that will be taken.  When the deficiencies have been corrected, record the date. Examples of items to review:

1.        Are all traffic control devices visible?

2.        Are they easy to read?

3.        Are they blocked by vegetation or other signs?

4.        Do any need to be repositioned?

Flagger

This section is used to describe any inadequacies or deficiencies with the Flagger or the Flagger Operations. If no inadequacies or deficiencies are noted, check "None" and continue to Traffic Flow Problems. If the Flagger or the Flagger Operations are not adequate, record the deficiencies and the corrective action that will be taken. When deficiencies have been corrected, record the date.  Examples of items to review:

1.        Are the flaggers positioned correctly and highly visible?

2.        Are they attentive to oncoming traffic?

3.        Are they flagging properly?

4.        Are they properly attired?

5.        Are the paddles/flags visible and clean?

6.        If a temporary traffic signal, are signal heads visible?

Traffic Flow Problems

Review for evidence of crashes, incidents, congestion points, delays, violations of PLCM, etc. If no evidence is noted, check "None" and continue to the Conformance/Adequacy with Traffic Control Standards section.  Record any evidence of crashes, incidents, or congestion points. If traffic flow problems exist, record the corrective action to be taken.  Examples of items to review:

1.        Are lane closures in accordance with allowed hours (PLCM)

a.        Permit, plans, contract?

2.        Is there evidence of skid marks and/or accident debris?

3.        Is there damage or reoccurring damage to traffic control devices?

Conformance and adequacy with traffic control standards

Review for non-compliances with OMUTCD, SCD, plans, or permit.  If no non-compliances are noted, check "None" and continue to the Interaction of Work Vehicles and Traffic section. If the standards are not adequate, record the corrective action to be taken.  Examples of items to review:

1.        Proper spacing between signs?

2.        Is the taper rate and drum spacing correct?

3.        Is there adequate buffer space?

4.        Is the work area protected?

Interaction of work vehicles and traffic

Review the interaction of work vehicles entering and exiting the work zone. If no inadequacies or deficiencies are noted, check "None.” If interactions are not adequate or safe, record deficiencies and record the corrective action to be taken.  Examples of items to review:

1.        Is there excessive braking for vehicles entering or exiting the work zone?

2.        Is there sufficient area in the work zone for work vehicles?

3.        Is there excessive dirt or mud on the road?

Proper storage of equipment and materials

Review the storage area of the equipment and materials in the work zone. If no inadequacies or deficiencies are noted, check "None.” If storage area is not adequate or safe, record deficiencies and record the corrective action to be taken.  Examples of items to review:

1.        Is the equipment and material properly protected or outside the clear zone?

2.        Is the equipment and material too close to open travel lanes?

Maintenance of traffic deficiencies and action taken

Notification: Verbal/Written

1.        Circle how corrective action information was provided.

2.        Record to whom the notification was provided.

Correct by date

Provide the date by which the corrections need to be made.

Corrected in a timely manner

1.        Circle “Yes” if the corrections were made by the date established at the time of the inspection.

2.        Circle “No” if the corrections were not made by that date.

Date corrected

Record date corrected.

Section(s) requiring correction(s)

Circle the letter which represents the section(s) which require remedial action.

Field review by               

Note your name and the date of the review.

Copy to: DWZTM/County Manager/Contractor/Construction or Other

Circle the entity and note who the copy(s) of the report form was given to.

Daily Documentation Requirements - 614 Maintaining Traffic

1.        Carry on Inspector's diary (Form CA-D-3) items of work performed by Contractor.  Erecting barricade fences, traffic zones established, flagger, or off-duty patrolmen used to control traffic

2.        What kind of sheeting do the signs have? G or H?

3.        All barricades and barrels are in good shape and have adequate reflectivity.

4.        When road is closed, document all items used (barrels, barricades, signs, etc.).  If a camera is available, taking a couple of snap shots is a good idea.

5.        A statement should be recorded daily on the Inspector’s diary to indicate whether traffic control was adequate for the work performed. Any accidents should be accurately documented.

6.        Locations required when placing temporary striping, reflectors, and barrier wall.

7.        Pay as per 614.16 of the C&MS.

615 Roads and Pavements for Maintaining Traffic

Documentation Requirements - 615 Roads and Pavements for Maintaining Traffic

1.        Document any work as if it were being performed as its own item (203, 442, 452, 616, etc.).

616 Dust Control

Ohio Administrative Code references, as seen in Section 107.19, address the regulatory requirements of controls required to address the discharge of fugitive dust during construction.  These Administrative Code sections are summarized in an Ohio EPA guidance document entitled, “Engineering Guide # 57.” 

www.epa.state.oh.us/portals/27/engineer/eguides/guide57.pdf

The guide describes, in a straightforward nature, Reasonably Available Control Methods (RACM) are required to comply with the law.

Documentation Requirements - 616 Dust Control

The minimum documentation and critical inspection requirements for Item 616 include recording the following inspection points in the project daily reports.  Specifications or other requirements waived by the Project Engineer should be noted in the daily reports.

1.        Measure or weigh water truck capacity to determine the water volume per load. 

2.        The units of measurement can be converted using the following conversions: 1 ft³ = 7.48 gal.; 1 lb. water = 0.12 gal.

3.        Record the bag count or weigh bills for calcium chloride when used.

617 Reconditioning Shoulders

Because of the simplicity of this item of work, no detailed explanation of the item is required in this manual.

Documentation Requirements - 617 Reconditioning Shoulders

1.        Materials.

2.        Place location or stationing where material was used.

3.        Shoulder preparation.

4.        Average depth and width.

5.        Spreading.

6.        How was material compacted?

7.        Attach initialed dated tape to tickets and convert as per Table 617.06-1 of the C&MS. 

8.        Measure and pay according to 617.06 and 617.07.

9.        Document on CA-D-1, CA-D-2, and CA-EW-12.  Do not duplicate the information on these forms unless necessary.

618 Rumble Strips on Shoulders

Because of the simplicity of this item of work, no detailed explanation of the item is required in this manual.

Documentation Requirements - 618 Rumble Strips on Shoulders

1.        Document Type 2 or Type 3.

2.        Measure and document width and depth of cut.

3.        Dust properly controlled.

4.        How were grindings disposed?

5.        Measure length for pay.

619 Field Office

Documentation Requirements - 619 Field Office

1.        Document on CA-D-3A.

2.        Pay in accordance with 619.03.

620 Delineators

General

This information is intended to serve as a guide for construction personnel where the Contractor furnishes and installs delineators.  However, it may be useful for maintenance personnel performing the same functions.  Inspection procedures are outlined.  This information points out the various important features and references the applicable specification or standard drawing.

Materials (620.02)

Make sure that all delineator materials used on a project are approved and listed on the Qualified Product List at the following website:

Item 720.01 Rectangular Reflectors

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=720.01

Item 720.03 Flexible Posts

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=720.03

Layout (620.03)

Figure 620.A – Delineator Lateral Placement, SCD TC 61.10

The top of the delineator post shall be 48 inches above the edge of the pavement.

The delineator post shall be placed 12 feet and 6 inches outside the outer edge of the pavement or the delineator post shall be placed 2 feet and 6 inches outside the outer edge of the shoulder.

Placement of delineator on curves and tangent sections.

Delineators shall be spaced 400 feet apart on the tangent sections.

Delineators on the horizontal curves shall be spaced according to the table in the SCD TC-61.10.

Delineators should be provided on the outside of horizontal curves on interchange ramps.

The color of the delineator reflector and flexible post shall conform to the color of the pavement markings nearest the delineator.

Figure 620.B – Spacing for Delineators, SCD TC 61.10

Figure 620.C – Delineator Placement on Ramps, SCD TC 61.10

Installation (620.05)

Delineators shall be installed facing traffic, except for red reflectors facing wrong-way traffic, if used.

Protective paper covering the face of flexible post-mounted reflectors shall not be removed until after installation.

Ensure that delineator posts are no more than 1:50 out of plumb. If soil conditions may cause the post to be out of plumb, the Contractor may drive a pilot shaft before installation.

Install the flexible posts using methods and equipment that conforms to the post manufacturer’s recommendations.

Documentation Requirements - 620 Delineators

1.        Document depth that post was placed on CA-D-3A.

2.        Document type of post and reflector on CA-D-3A.

3.        Total of each color and location where they were placed on CA-D-3A.

4.        Turn in total of all colors for pay on CA-D-3A.

621 Raised Pavement Markers (RPM)

General

This information is intended to serve as a guide for construction personnel where the Contractor furnishes and installs raised pavement markers.  However, it may be useful for maintenance personnel performing the same functions.  Inspection procedures are outlined.  This information points out the various important features and references the applicable specification or standard drawing.

Conduct 25 percent to 75 percent inspection during the installation activities, which include daily start-up, intermittent, and end of day inspection.  Additionally, conduct 80 percent to 100 percent inspection of all installed RPMs prior to final acceptance.

Materials (621.02)

Make sure that all RPM materials used on projects are approved and listed on the Qualified Product List at the following website:

Item 721.01 Raised Pavement Marker Castings

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.01

Item 721.02 Prismatic Reflectors

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.02

Item 721.03 Raised Pavement Marker Castings Adhesive

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.03

Item 721.04 Prismatic Reflectors Adhesive

http://www.odotonline.org/materialsmanagement/qpl.asp?specref=721.04

Installation RPM Casting (621.04)

References:

1.        Brochure for RPM Installation Procedure.

2.        See Traffic Engineering Manual, Section 350-3 at the following website:

http://www.dot.state.oh.us/Divisions/HighwayOps/Traffic/publications2/TEM/Documents/Part_03_071808_bookmarked.pdf

RPMs shall be placed when the pavement surface temperature and the ambient air temperature is at least 40 °F (5 °C) and the pavement is dry.

RPMs shall not be placed under the following conditions:

1.        On pavement surfaces with cracking, spalling, or failure of underlying base material.

2.        Within 1 foot (0.3 m) of active signal detector loop wires.

3.        Over pavement markings, except with the Engineer’s approval.

4.        Closer than 2 inches (50mm) to a pavement construction (transverse or longitudinal) joint or within an intersection.

5.        Within 3 feet (1 m) of a bridge expansion joint.

Procedure for RPM Casting Installation:

1.        Casting installation.

Figure 621.A – Typical Saw Cut

a.        Pavement must be cut to the dimensions for the casting being used.

2.        Casting in saw cut without epoxy.

Figure 621.B

a.        Each pavement cut must be inspected prior to adding epoxy.

b.        When a casting is inserted in the cut without epoxy, all four leveling lugs/tabs must contact the pavement surface.

All four keel-ends of castings must be below the surrounding pavement surface.

3.        Casting centered in saw cut lengthwise.

Figure 621.C

a.        Each casting must be centered lengthwise and should have 1/8-inch (3 mm) clearance between pavement cut and casting for epoxy to bond properly.

b.        Only the leveling lugs/tabs should be in contact with pavement surface after insertion of casting in pavement so that a minimum of 1/8 inch (3 mm) of epoxy is the bonding adhesive between casting and pavement.

c.        The pavement cut must be completely dry and free of dust, dirt, or any other material that will interfere with the adhesive bond.

d.        Epoxy on the active reflector face must be removed immediately.

e.        Saw cut – casting fit must be periodically checked as saw blades wear to ensure correct dimensions are maintained.

4.        Properly installed RPM with epoxy around casting.

Figure 621.D

a.        Two component epoxy adhesive approved (must be on QPL) is to be used to fill the pavement cut to within 3/8 inch of top of pavement cut prior to placing casting.

b.        After placing casting:

The four leveling lugs/tabs must be in contact with pavement surface.

The epoxy should ooze out from under the casting of all sides, filling all voids around the casting, and be level with pavement surface.

Reflector Replacement (621.06)

References:

1.        Brochure for RPM Installation Procedure.

2.        See Traffic Engineering Manual Section 350-3 at the following website:

http://www.dot.state.oh.us/Divisions/Operations/Traffic/publications2/TEM/Documents/Part_03_Complete_042012Revision_bookmarked_042012.pdf

Procedure for Reflector Replacement:

1.        Remove reflector.

Figure 621.E

a.        Pry old reflector out of casting.

b.        Use eye protection when replacing reflector.

2.        Clean the casting.

Figure 621.F

a.        Scrape old pad material and adhesive out of reflector pocket, using an air hammer or wire brush.

b.        Sandblast the casting pocket to remove all residual adhesive, rust, and other contaminants from the casting.

c.        It is important that the casting is clean to ensure long-lasting performance.

3.        Apply adhesive.

Figure 621.G

a.        Peel the release liner from the back of the reflector.

b.        Apply a wide bead, approximately 3/8 inch, of an adhesive (as approved ODOT QPL) in the center of the adhesive pad on the back of the reflector.

4.        Install reflector into casting.

Figure 621.H

a.        Place the reflector into the casting pocket.

b.        Apply foot pressure on the reflector for 1 to 3 seconds.

c.        Adhesive must flow out around all edges of the reflector to indicate that the adhesive completely covers the entire bottom of the reflector and provides a uniform adhesive layer between the reflector and the casting.

Remedial Actions for Poorly Installed RPM Castings

This information is intended to serve as a guide for construction and/or maintenance personnel where the RPM castings are poorly installed. It provides a guide to the necessary remedial action to fix the problem.

The RPM casting shall be installed properly according to the following references:

1.        Item 621.03, “Layout.”

2.        Item 621.04, “Installation of RPM Casting.”

3.        Standard Construction Drawings TC-65.10 and TC-65.11.

The following information provides examples of defectively installed RPM castings and describes remedial action to fix the problem.

Defective Installation: The RPM is installed with all four lugs/tabs not resting on the pavement as shown in Figure 1 below:                          

Figure 621.I

Remedial Action:

Remove and reinstall the RPM casting at a new location.

New RPM location shall not exceed 25 percent of the specified RPM spacing.

If necessary to relocate the RPM to a distance greater than 25 percent of the RPM spacing, do not install the affected RPM. 

Fill the old cavity on the roadway surface with epoxy or asphalt concrete from where the RPM casting is removed.

Defective installation: The RPM is installed, but does not fill the voids with epoxy around the casting or the RPM is installed, but the epoxy is not around the casting to the surface of the pavement as shown in Figure 2.

Figure 621.J

Remedial Action:

Blow out dirt from around casting with compressed air.

Fill the voids and seal the RPM casting all around with epoxy as shown in Figure 3.

Figure 621.K

Defective installation: The RPM casting is installed near or on a longitudinal joint or crack on the roadway surface as shown in Figure 4.

Figure 621.L

Remedial Action:

Seal all the cracks with epoxy up to 9 inches from the RPM casting as shown in Figures 5, 6, and 7.

Figure 621.M

Figure 621.N

Figure 621.O

Defective installation: The RPM is installed, but the epoxy adhesive is not hardened, or the epoxy adhesive is not uniform gray in color as shown in Figure 8.

Figure 621.P

Remedial Action:

Remove and reinstall the RPM casting at a new location.

New RPM location shall not exceed 25 percent of the specified RPM spacing.

If necessary to relocate the RPM to a distance greater than 25 percent of the RPM spacing, do not install the affected RPM. 

Fill the old cavity on the roadway surface with epoxy or asphalt concrete from where the RPM casting is removed.

Defective installation: The RPM is installed on construction joints which have extensive failure as shown in Figure 9.

Figure 621.Q

Remedial Action:

Remove and reinstall the RPM casting at a new location.

New RPM location shall not exceed 25 percent of the specified RPM spacing.

If necessary to relocate the RPM to a distance greater than 25 percent of the RPM spacing, do not install the affected RPM. 

Fill the old cavity on the roadway surface with epoxy or asphalt concrete from where the RPM casting is removed.

Raised Pavement Markers Removed

Remove raised pavement markers in concurrence with the maintenance of traffic phases so that their existence or removal will not conflict with the temporary pavement markings or snow and ice removal.

Remove all standing water and fill with asphalt concrete. By the end of the next workday, depressions will be caused by removing the castings.  Compact the asphalt concrete flush with the pavement.

Documentation Requirements - 621 Raised Pavement Markers

1.        Verify castings to be used are on the Qualified Products List (QPL) before permitting installation.

2.        Verify the epoxy to be used to install the casting is on the Qualified Products List (QPL).

3.        Make sure that the keels of the casting are placed into the slots so that the tips of the RPM snowplow deflecting surfaces on the keels, which are below the pavement surface, and all four lugs/tabs on the keels of the casting, are in contact with the pavement.

4.        Check before placement of the epoxy, the saw cut is clean of all loose material and dry. Saw cut should have 1/8-inch clearance on all sides of the casting.

5.        Verify ambient air temperatures are at least 40 °F and the pavement is dry.

6.        Check epoxy is an A+B mixture, thoroughly mixed (grey color), and in accordance with manufacturer’s recommendations.

7.        Check that sufficient epoxy is in and between the slots to ensure that all voids beneath and around the casting are filled.

8.        Placement of RPM castings shall be 6 inches from any construction joint (lateral or longitudinal).

9.        Location and stations are per Standard Construction Drawings TC 65.10 and TC 65.11.

10.     Check quantity totals for payment.

11.     Document on CA-D-3B.

12.     Verify RPM reflectors to be used are on the Qualified Products List (QPL) before permitting installation.

13.     Verify that all dirt, dust, oil, grease, rust, moisture, parts of damaged reflectors, or any foreign matter is removed that impairs adhesion of the reflector to the casting.

14.     Verify reflector area of the castings shall be sandblasted to 80 percent bare metal.

15.     Verify the application of adhesive is in a single bead, sufficient to squeeze out on all sides of the reflector when pressure is applied, to seat the reflector and seal out moisture.

16.     Document on CA-D-3B.

622 Concrete Barrier

Description (622.01)

This work consists of furnishing and placing Portland cement concrete barrier on the accepted and prepared subgrade, subbase course, or existing pavement.  This item consists of furnishing, placing, maintaining, and removing portable concrete barrier.

Placing Concrete (622.03) 

The concrete barrier will be constructed by either cast-in-place, precast, or slip-form methods.  For slip-form construction, conform to 609.04.C.  For cast-in-place construction, conform to the proper SCD.

1.        RM- 4.3 Single Slope Barriers.

2.        RM- 4.4 Single Slope Barrier Transitions.

3.        RM- 4.5 Single Slope Barrier, Type D.

4.        RM- 4.6 Concrete Barrier End Sections.

Portable Concrete Barrier (622.04)

The individual sections of PCB shall be no less than 10 feet (3 m) long. See SCD RM- 4.2, 32-inch Portable Concrete Barriers for details.  If intending to use the barrier at one location on the project, the Contractor may slip-form barriers in place without joints or with grooved or sawed joints to facilitate removal. Any barrier sections damaged during handling or by traffic shall be either repaired or replaced for the life of the project.

Joints (622.05)

The joints for cast-in-place or slip-formed barriers shall be constructed of the type and dimensions and at the locations specified in the plans.

Contraction Joints 

The Contractor may construct unsealed contraction joints by sawing using metal inserts inside the forms, using a grooving tool, or using full-width, 3/4 inch (19 mm) thick, preformed joint filler conforming to 705.03.  Joints shall be sawed, tooled, or formed by inserts a minimum of 1/8 inch (3 mm) wide and 3 inches (75 mm) deep.  The joints should be sawed to the required depth with minimal spalling of the concrete surface as soon as curing allows.

Expansion Joints 

The 3/4-inch (19 mm) thick, preformed joint filler shall conform to 705.03 to construct expansion joints.

Horizontal Construction Joints 

If, and as shown on the plans, the Contractor may place horizontal construction joints.

Finish (622.06)

Check the surface of the barrier with a straightedge for irregularities of more than 1/4 inch in 10 feet (6 mm in 3 m) after the Contractor has checked and made corrections.  Document any findings on CA-D-3.

Curing (622.07)

Concrete curing shall be according to 511.17, Method B, and the following additional requirements.  Ensure that the curing compound is approved.  For small areas, allow the use of other acceptable methods.

Do not allow any load or any work that will damage newly placed concrete. A minimum of 36 hours of cure time is required on any concrete placed first at a horizontal construction joint.  The Contractor may cure precast sections according to 515.15.  The Contractor may use radiant heated forms for curing.

The Contractor may use 511.17, Method A for curing of short sections of barrier (leave-outs); however, before the curing is completed for any leave-outs, material conforming to 705.07, Type 2 at the normal rate specified in 511.17, Method B shall be applied.

The Contractor may cure horizontal construction joints between the foundation and the upper portion of the barrier, and between portions of the upper barrier placed separately according to 511.17, Method A or B.  The membrane should not be removed before placing the next portion of the concrete barrier.

Method of Measurement (622.08)

Measure concrete barrier by the number of feet (meters) along the centerline of the top of the barrier, including all transitions, end terminals, and bridge pier sections as specified, complete in place.

Measure portable concrete barrier and portable concrete barrier, bridge mounted by the number of feet (meters) for each application of the barrier placed according to the plans.  Measure each re-use of barrier sections at a different location required by the plans separately.

Do not measure repaired or replacement barrier sections which are damaged during handling or by traffic.

Basis of Payment (622.09) 

The cost of all inserts, sleeves, fittings, connectors, reinforcement, dowels, preformed filler, excavation, and backfill is incidental to these items.

Documentation Requirements

1.        Form dimensions.

2.        Conform to section 609.04C if slip formed.

3.        Number and clearance maintained on reinforcing steel if any used.

4.        Joint spacing and thickness of expansion material used.

5.        Joints saw cut, formed with metal plates, or expansion material

6.        Amount of curing compound required and used. 

7.        Measure length for pay.

8.        Use form CA-D-3 for documentation.

623 Construction Layout Stakes and Survey Monuments

Description (623.01)

With the 2013 C&MS, all survey monuments were moved to this section from Section 604.

All surveying work related to locating and setting reference monuments, Right-of-Way monuments, and setting steel rods in monument assemblies must be performed under the direction of a Registered Surveyor. According to the Ohio Revised Code, a Registered Surveyor must perform the work associated with property boundaries. Either a Registered Surveyor or Registered Engineer can supervise other surveying work to set project control and construction layout stakes.

Verification

Before beginning any construction activities that might disturb existing survey monuments, the Contractor must have a Registered Surveyor verify the location of existing survey monuments that are listed in the Contract Documents.  The Registered Surveyor must prepare a report and submit it to the Engineer and District Survey Operations Manager.  If the Contractor submits the verification report to only the Engineer, then send a copy to the District Survey Operations Manager.  If the Surveyor finds any survey monuments not listed on the Contract Documents, the surveyor must survey their location and include them in the verification report.

Placement, Protection and Restoration of Survey Monuments

The Right-of-Way designer will include quantities for proposed monument assemblies and reference monuments in the Right-of-Way plans.  Also, the Right-of-Way designer will include quantities to replace any survey monuments that are located within a temporary easement and that they expect the Contractor to destroy during the work.  The Contract Documents should include pay items to replace any survey monuments that the Contractor can’t help but destroy during the progress of the work.  However, the Contractor may also destroy or damage survey monuments due to carelessness or inattention.  The Contractor must replace these survey monuments at no cost to the Department.  If the Department ends up having to replace survey monuments that are damaged by the Contractor, then deduct all costs incurred by the Department from the Contractor’s estimate.

In some cases, the Contractor will not have to replace an existing survey monument when it is destroyed as a result of the work.  For example, when the Department is acquiring additional Right-of-Way, the old Right-of-Way monuments will be abandoned and do not need to be replaced.  This is why the phrase, “unless directed otherwise by the Engineer,” is included in the sentence, “Restore survey monuments damaged or destroyed by construction activities, unless directed otherwise by the Engineer.”  Contact the District Survey Operations Manager if there are any questions.

When the Contractor sets new survey monuments, they or he/she must have a Registered Surveyor prepare a report similar to the verification report.  The Contractor submits this report to the Engineer and District Survey Operations Manager.  If the Contractor submits the verification report to only the Engineer, then send a copy to the District Survey Operations Manager.  Refer to Standard Construction Drawing RM-1.1 for details about the different types of survey monuments.

Providing Electronic Instrumentation

Contractors use global positioning methods to perform construction control on many projects.  If a pay item for providing electronic instrumentation is provided in the Contract Documents, then the Contractor provides one GNSS receiver for the project staff to use for verifying locations and elevations.  GNSS stands for Global Navigation Satellite System. It is like the Global Positioning System (GPS) but includes satellites run by countries other than the United States.  For large projects, the Contract Documents may include an, “as per plan,” item that requires the Contractor to provide two or more GNSS receivers.  The Contractor must also provide training to use the equipment and provide technical assistance throughout the project duration.  At the end of the work, the equipment is returned to the Contractor.

If the District decides to use its own GNSS receivers to inspect the work, the Contractor must still provide the model files that the Contractor is using to perform the project control. However, in this case, there is no guarantee that the model files will work with the District’s equipment.  The District may have to convert or translate the files.

Documentation Requirements - 623 Construction Layout Stakes

1.        Verification report for all existing survey monuments. Must be signed and sealed by a Registered Surveyor.

2.        Report giving the coordinates, station, offset, and description of each new or replaced survey monument. Must be signed and sealed by a Registered Surveyor.

3.        Copy of the construction layout notes for each portion of the work.

624 Mobilization

Documentation Requirements - 624 Mobilization

1.        Document on CA-D-3A.

2.        Pay in accordance with 624.02.

625 Highway Lighting

General 625.01

The following information does not alter or supersede the Contract Documents.  It is provided as a guide for ODOT personnel assigned to a project to help them with their work.

Electrical construction work must adhere to the Contract Documents which commonly include proposal notes, project plans, Standard Drawings, and Construction and Material Specifications.  In addition, there may be building or electrical codes or change orders that must be followed.

Contractor Prequalification

Only Contractors prequalified by the ODOT Office of Contracts for Work Type 43 - Highway Lighting shall be allowed to do the highway lighting items of work on the project.

Respect for Contractor

Contractors are prequalified for specialized work types.  They bring expertise to the project and an independent perspective from the project management team.  As the Contractor reviews plans and specifications, he wants to ensure that he can install material that will ultimately operate as the designer intended.  The Contractor relies on the Engineer to guide the project, to approve materials and work, and to ensure that he will be paid for work completed.  It is important to remember that even when the roles of the project team and the Contractor conflict, successful completion of the project relies on all those involved and the maintenance of good working relationships.

Protection of Utility Lines

The Contractor is to notify all utilities before construction work begins.  Names and addresses of these utilities are given in the project plans.  It is the Contractor’s responsibility to contact the Ohio Utility Protection Services (1-800-362-2764) to have utility locations marked in all areas where digging is involved.

Plan Discrepancy, Design Ambiguity, Consultation with Designer

When there is a question regarding the intent of the plan, the Engineer should:

1.        Define the discrepancy or ambiguity.

2.        Determine if more than the highway lighting is affected.

3.        Identify the standard drawings and specification pertinent to the situation.

4.        Determine potential solutions.

5.        If the issue involves the location of the luminaires or light poles, the mounting height of the luminaries above the pavement, the luminaire to be used or the lamp to be used, the Engineer should consult ODOT’s design office and the Designer to ensure that the performance goals for the lighting system will still be met by the solution under consideration.

6.        Consider the maintenance of the installation if the solution is implemented.  Will parts not normally stocked by the maintaining agency be required, or will tools and equipment not normally at the disposal of the maintenance crews be required, or will special training of the workers be required?

7.        Evaluate potential solutions for safety.  Consider measures needed to keep errant vehicles from striking the item, the danger to those who must maintain the installation, and the danger to traffic from the maintenance activities.

8.        Determine if applicable codes and regulations will be met.  Commonly involved will be the National Electric Code, The National Electric Safety Code, and Utility Company requirements.  There may also be state and local building codes.

Materials (625.05)

Highway lighting items are found in 625 with detailed descriptions of materials in 725.

In general, all material furnished shall be new and of first quality, unless otherwise noted in the plans, and shall be identified either by a permanently attached name plate or by an indelible marking.

Before installation, all material shall be checked to determine that it is indeed the material that has been specified, the appropriate material process has been completed, and all paperwork is in hand. 

Four procedures are commonly used to ensure that the correct materials are installed.

1.        Qualified Products List (QPL).

2.        ODOT Plant Sampling and Testing Plan (TE-24 Certification).

3.        Certified Drawings or Certified Catalog Cuts.

4.        Project Inspection of Material.

Qualified Products List

Lighting material which may be on a Qualified Products List:

1.        Pull box.

2.        Junction box.

3.        Conduit.

4.        Wire and cable.

5.        Ground rod.

6.        Photocell.

The Office of Materials Management maintains the Qualified Products Lists.  The Engineer can verify that the material is on a Qualified Products List (QPL) through ODOT’s SiteManager.  After verifying that the material being supplied is that specified by the Contract and on such a list, the project may accept the material. 

TE-24 Material Certification

Lighting material for which TE-24 Certification may be obtained:

1.        Pull box. 

2.        Junction box.

3.        Anchor bolt.

The ODOT Plant Sampling and Testing Plan (TE-24 system) is administered by the Office of Materials Management.  This system was designed to allow certain material to be sampled, tested, approved, and stocked for future use on ODOT projects.  The material is inspected at the manufacturing or distribution site.  Each approved lot of material is assigned a certification number and documented on Form TE-24.  Material from the approved lot may then be transferred directly to an ODOT project or it can be transferred to other warehouses, such as a Contractor’s storage facility, and then transferred to a project at a later date.

Working Drawings (625.06)

Lighting material requiring Certified Drawings or Catalog Cuts:

1.        Luminaires.

2.        Luminaire supports (towers, lowering devices, poles, bracket arms).

3.        Power service equipment.

4.        Portable power units.

5.        Temporary lighting systems.

The Contractor shall submit two copies of shop drawings or catalog cuts prior to the installation of the material.  The submittal ensures that the state has a good record of the material installed should there be any question about the material meeting criteria or should additional or replacement units be required.

Each submittal shall identify the project and the bid reference number under which the item is being provided.  Drawings or catalog cuts shall be clearly marked by circling or underlining to indicate the exact item and options being supplied.  If a given item is to be supplied under multiple bid item reference numbers, separate and complete documentation packages shall be submitted for each bid item reference number.  If multiple items are to be supplied under a single bid reference number, all the items to be supplied under said reference number shall be submitted as a package.  The Contractor’s cover letter for each package is to certify in writing that each manufactured item in the package conforms to all contract requirements for that item.

The submittal of certified drawings or catalog cuts does not relieve the Contractor from furnishing additional information concerning the material deemed necessary by the state.

Project Inspection of Material

The following materials are normally manufactured to standards that meet ODOT criteria and therefore do not have a QPL, do not normally have a TE-24, and shop drawings or catalog cuts are normally not required:

1.        Exothermic welds.

2.        Insulating varnish.

3.        Split bolt connector.

4.        Expansion fittings.

5.        Connector kits.

6.        Splice kits.

7.        Copper crimps and compression connectors.

8.        Light pole decals.

9.        Circuit identification tags.

10.     Cable grips.

11.     Wood service poles.

12.     Fuses for control center and connector kits.

13.     Photoelectric cell and bracket.

14.     Secondary lightning arrestor.

15.     Guy anchors and anchor rods.

16.     Weather heads.

17.     Watertight hubs.

18.     Remote ballast enclosures and mounting brackets.

Project inspection of material is used to verify that the material at hand is listed on a QPL or described on a TE-24 for which certified shop drawings or catalog cuts have been received and that the material complies with the requirements of the Contract Documents.  For material not on a QPL, which does not have a TE-24, and for which shop drawings or catalog cuts are not required, the project inspection of material is limited to comparing the material at hand with the requirements of the Contract Documents.

Luminaires (625.08)

A luminaire consists of a housing which contains a reflector, refractor, lamp socket, and lamp. Unless otherwise specified, the housing will also contain the ballast components (core and coil, capacitor, starter) required for the lamp being used. The housing may have optional components, such as fuses or a photocell when specified. The housing is fitted with the necessary clamps or other provisions for attaching the luminaire to its support and terminal block for the incoming power.

Verify that the luminaire installed at each location is one of the luminaires listed in the plan for that location.  Verify that the distribution, lamp type, and lamp wattage are as specified in the plans.  Instructions packed with the luminaire will explain the distributions that the luminaire is capable of producing and how to set any adjustments in the luminaire to provide each distribution.  Verify that ballast is compatible with the circuit voltage and lamp.

Conventional Luminaire

The conventional luminaire used by ODOT is also known in the trade as an “Ovate” or “Cobra Head” fixture.  It may be equipped with a flat or a dropped style refractor as specified.

Verify that the luminaire is properly leveled according to the instructions packed with the luminaire.

Side-Mount Roadway Luminaire

This luminaire reminds one of a floodlight.

Verify that the “tilt” has been set as specified in the plan according to instructions packed with the luminaire.  Verify that the luminaire is oriented “normal” to the line of survey for the roadway being lighted unless the plans stipulate otherwise.

High Mast Luminaire

These luminaires are mounted on tall structures equipped with devices to bring the luminaires to ground level for servicing. 

Verify that the luminaire is not “twisted” with regard to its bracket arm.  There are three distributions commonly used.  If the luminaire has a rotatable refractor, verify that it has been aligned properly.

Low Mast Luminaire

Low mast luminaires are the same luminaire as a high mast luminaire, but installed as a fixed unit on a pole of more traditional height.

Verify that the luminaire is not “twisted” with regard to its bracket arm.  There are three distributions commonly used.  If the luminaire has a rotatable refractor, verify that it has been aligned properly.

Underpass Luminaire

Underpass luminaires are used to light roadways beneath bridge decks.  Commonly they are wall mounted on a pier cap or abutment.  Sometimes they may be ceiling mounted on the underside of the deck or to a panel attached to the deck supporting beams or pendant mounted on suspension pipes attached to the structure.  Occasionally they will be post top mounted on short poles.

Verify that the luminaire has been attached to the structure at the location and in the manner specified.

Lamps

Verify that the lamp is one of the brands listed in the plan. Verify that the lamp type and wattage is compatible with the luminaire and its ballast.  Unless otherwise specified, for a particular installation, the lamps are to have clear envelopes.  Do not substitute lamps with “frosted” envelopes.  Verify that the installation date has been properly marked on the base of the lamp.  Instructions packaged with the lamp explain how to use the dating provision built into the base.

Luminaire Supports (625.09)

The inspection of the supports (poles, arms, towers, lowering devices, brackets, etc.) consists of two phases: (1) inspection of the components and (2) inspection of the completed assembly.  While these may be done together, it is better if the components are inspected upon arrival at the project since there is more time to obtain replacements or correct faults.

Inspection of Support Components

Three areas are examined in this phase: welding, galvanizing, and compliance with shop drawings.

Inspection of Welds

Examine each weld for the following:

1.        Each of the welds called for by the certified shop drawings is present and there is no weld present that is not shown on said drawings.

2.        There is no misalignment of the parent material being joined by the weld.

3.        There has been no warping of the parent material by the weld.

4.        Each weld is of the type, size, and continuity shown on the shop drawings.

5.        Each weld is of full cross-section without excessive concavity or convexity.

6.        There is no over filling or cratering at either the beginning or end of the weld.

7.        There is no undercutting (a shallow groove melted into the base metal adjacent to a weld and left unfilled by weld metal) along any weld.

8.        There is no porosity (pitting or pinholes) in any weld.

9.        There is no crack or discontinuity in either the base metal or weld material along any weld.

Inspection of Galvanizing

Examine the galvanizing for the following:

1.        There are to be no spots where the galvanizing is missing or loose and can be flaked off with a penknife.

2.        There should be no ash that has been picked up from the top of the bath which usually appears as coarse lumps.

3.        There should be no pimples from entrapped bath scum particles.

4.        There should be no blisters from hydrogen gas absorbed during pickling being released and rupturing the surface of the galvanizing.

5.        There should be no flux inclusions from flux picked up from the top of the bath during dipping and burned on during immersion.

6.        There should be no lumps or runs of excess zinc from delayed run-off of molten metal trapped near surface discontinuities, such as joints, seams, or holes as the part was lifted from the bath.

7.        There should be no rust stains from impurities from the pickling process weeping at seams and folds.

8.        There should be no general overall roughness from over pickling or of excess zinc bath temperature and/or immersion time.

9.        There should be no patches of dull, gray coating from slow cooling of heavier cross-sections of the part after immersion.

10.     The galvanizing should have a uniform appearance.

Excessive galvanizing faults, gross imperfections, or overall poor workmanship may be cause for rejection of the support.  Minor scratches in galvanized surfaces can be accepted.

Compliance with Shop Drawings

Supports are frequently shipped to the job site and stored prior to assembly and erection as components which give opportunity for the components to get mixed up leading to improper assemblies since the basic design often does not prevent errors.  Therefore, prior to beginning the assembly of a given support, it is necessary to check the major dimensions of the various components against the shop drawing for the support to verify that this has not occurred.

On poles, verify the length, base diameter, top diameter, and wall thickness of each pole, or section of the pole, for poles shipped in multiple sections that are field assembled.  Verify the length, width, and thickness of the base plate along with the bolt circle diameter, bolt hole size, and number of anchor bolt holes provided.

On bracket arms for conventional supports, verify the arm length and arm rise.

On lowering devices, verify the diameter of the luminaire mounting ring and number of luminaire arms on the ring.  Also, verify the length of the power cord along with the wire size and number of conductors in the cord. Verify the diameter and length of each piece of hoisting cable.

Assembly of Supports

Support components stored in the field should be kept off the ground to prevent finish blemishes where the component lay in contact with a damp surface earth or water.  Support components and assembled supports should be loaded, transported, unloaded, stored, and erected in a manner avoiding damage to the factory applied surface finishes.

On multi-piece poles, verify that the sections to be assembled are the correct pieces for the pole at hand.  Before tightening each telescopic joint between the sections, verify that the sections are properly oriented and that the male section has been marked to indicate when full insertion has been achieved.  Verify that the process used for tightening the joint between sections is approved by the pole manufacturer and that the pole is not bent during the tightening process.

On each steel light pole used with an aluminum transformer base, verify that both the bottom of the pole base plate and the top of the transformer base were given a coat of zinc rich paint prior to assembly.

On each light pole, verify that the cable grip in the light pole is properly installed as shown in SCD HL-10.12 to prevent damage to the pole and bracket cable.

On each light tower, verify that the luminaire ring has the correct number of mounting arms and that each arm is attached such that when the tower is erected, the arms will be in the positions relative to the roadway as shown on SCD HL-10.31.  If the lowering device is equipped with top laches, verify that when the luminaire mounting ring is fully raised and latched, the latch indicator on each latch will be in the “extended” or “visible” position.  Verify that all moving parts on the head frame assembly and hoist mechanism have been lubricated in accordance with the manufacturer’s instructions.

Verify that all parts are in place and all fasteners have been properly installed according to the manufacturer’s instructions.

Verify that each hand hole door or cover closes with no excessive gaps.

Verify that a light amount of anti-seize or grease lubricant has been worked into the threads of each fastener which hold each removable cover in place.

Erection of Supports

Prior to erection, verify that nuts can be easily turned by hand onto the threads of each anchor bolt.

When leveling nuts are to be used, verify that the leveling nuts are level before beginning the lift to set the support.

Each support should be lifted and set by crane with the hoist line attached at a point as far above the support’s center of gravity  as possible, with a tethering cable from the lifting point to the base of the pole.  The lifting point on poles made up of sections slip fitted together should be above the uppermost joint.  Hoisting should be smooth and continuous without abrupt jerks.  Light tension should be maintained in the hoist lines until an anchor nut has been threaded onto each anchor bolt far enough that the bolt is projecting though the nut by a full thread.

Verify that each support with a transformer base has been plumbed using leveling shims approved by the base manufacturer, installed between the base and the foundation according to the base manufacturer’s instructions and limitations and that the anchor nut on each anchor bolt has been properly tightened.

Verify that each support with an anchor base installed directly on a foundation, without leveling nuts, has been plumbed using leveling shims approved by the pole manufacturer. Each support is installed between the base and the foundation, according to the pole manufacturer’s instructions and limitations, and the anchor nut on each anchor bolt has been properly tightened.

Verify that each support with leveling nuts is plumbed by adjusting the leveling nuts. Verify that both the anchor nut and the leveling nut on each anchor bolt are properly tightened.

Verify that a light tower has been plumbed early in the morning when the heat effect from the sun is at a minimum.

Verify that each support has been plumbed when there is no appreciable wind.

Verify that the space between the top of the foundation and the base of the support has not been grouted.

When a high mast support (light tower) is equipped with a lowering device that has top latches, verify that the ring engages all latches simultaneously. This is often referred to as “leveling” the ring.  It should be done following the manufacturer’s directions.  Generally the procedure is to place a block on each hoisting cable which is attached to the ring a few inches above the ring in such a manner that the block will slide along the cable when the block contacts the portion of the mechanism at the top of the tower. The ring is then raised until all blocks have made contact, but not fully raised.   The ring is lowered and the distance between each block and ring is measured. Hoisting cables are adjusted to make the measurements equal. The process is repeated until no further adjustments are required.  The blocks are removed and the lowering device operated several times through its full cycle watching all latches for proper operation.

Verify that support identification decals have the proper legend and the decals are located approximately 7 feet (2.1 m) above the base of the pole facing oncoming traffic.

Foundations (625.10)

Foundation inspection normally consists of three parts: location, excavation and concrete placement.

Foundation Location

After the location of each foundation is staked, verify that the location is specified in the plan and that Ohio Utility Protection Service and all utilities in the area have been allowed at least 48 hours to mark their utility locations relative to the proposed foundation.  Verify that the location appears logical.  Be alert for the following:

1.        Installing the lighting item at the staked location will require removal of vegetation that shields adjacent property owners from the highway.

2.        Installing the lighting item at the staked location will locate the item at the top of the back slope, in a cut cross-section, or at the bottom of the fill in a filled cross-section where guardrail is to be used to keep errant vehicles from going down the slope.

3.        Installing the lighting item at the staked location will place the item under an overhead utility line or over an underground utility line.

4.        Installing the lighting item at the staked location will require a graded access drive for the construction that has not been addressed in the plan.

The designer should be consulted prior to relocating any support more than 10 feet (3.0 m) or if two or more adjacent supports need to be relocated.

Excavation

Foundations are to be placed only in undisturbed soil or compacted embankment.

If a minor cave-in should occur, the Contractor may, with the approval of the Engineer, continue to excavate using sleeving or casing.  When bedrock is encountered, the Engineer may reduce the specified foundation depth.

If construction crews must leave the job site with a hole unfilled, it shall be covered and marked with cones, barrels, or warning tape.

Placement of Concrete

Verify that the top of the foundation will be at the proper elevation.

Tops of foundations shall be finished smooth and level to enable proper plumbing of the light pole.

Verify that the anchor bolts are of the correct size and number and that each bolt is securely held in the correct position.  The use of an anchor bolt setting template is encouraged.  Verify that each anchor bolt will project the proper distance from the foundation.

Verify that conduit ells are present and that each ell is of the correct size and material and properly oriented.

Verify that all reinforcing bars are present and that each is of the correct size and shape.

Verify that all items to be cast into the foundation, along with any forming aids, are secured in such a manner that they will not move out of position during the placement of concrete.

Verify that water encountered in the foundation excavation is pumped out before concrete placement.  If this is not feasible, verify that the concrete is placed by the tremi-tube method.

Verify that the concrete is of the proper design, has been properly mixed, has the correct slump, and is properly handled during placement.  Verify that the concrete is vibrated to eliminate voids.

Verify that the top of the foundation is properly finished and that the concrete is properly cured.

Junction Boxes (Handholes) & Pull Boxes (Manholes) (625.11)

Junction Boxes (Handholes)

Verify that each junction box is of the correct size and material and securely fastened in the correct location.  Verify that a light amount of anti-seize or grease lubricant has been worked into the threads of each fastener holding the cover in place.

Pull Boxes (Manholes)

Verify that each pull box is of the size and material specified.

Verify that each pull box is at the planned location unless the planned location puts the box in a low spot with respect to the surrounding surface.  In such cases, notify the Engineer so that the Engineer, in consultation with the designer, may attempt to move the box to a location where it will be less likely to hold water. 

Verify that a light amount of anti-seize or grease lubricant has been worked into the threads of each fastener holding the cover in place.

Raceways and Conduits (625.12)

Verify that each conduit run is of the correct size and material.

Verify that each cut end on each piece of conduit is reamed to remove rough edges.

Verify that all field cut threads on galvanized conduit have been coated with zinc rich paint.

Verify that each expansion or deflection fitting has a bonding strap for ground continuity when used with metal conduit.

Verify that each conduit run has been properly fastened in place.

Verify that the Contractor shall check each run of conduit by rodding (pushing a mandrel through the empty conduit) or pulling a cleaning puck through the conduit.

Verify that each run of conduit being left empty for future use contains a No. 10 AWG pull wire or equivalent.

Verify that each end of each conduit run is terminated either in a box connector that contains an integral bushing or with a separate bushing to protect cable pulled into the conduit.

Trenching (625.13)

Verify that the trench did not deviate more than 6 inches (150 mm) from the designated line, unless such deviation has been approved by the Engineer.  Verify that the sidewalls and bottom of the trench do not have any protruding sharp rocks.

When duct-cable is installed in the trench, verify that the backfill material within 2 inches (50 mm) of the duct-cable does not contain pieces larger than 1/2 inch (13 mm).

Verify that the backfill is placed in compacted layers exceeding no more than 4 inches (100 mm) in thickness.

When caution tape is specified, verify that the tape is installed 6 inches to 8 inches (150 to 200 mm) below grade.

Power Service (625.15)

Power service includes all equipment from the connection point to the utility company to the beginning point of the individual lighting circuits.

Verify that the power service location will be readily accessible to both maintenance personnel and utility company personnel.  There should be a safe parking area for service vehicles since the site will be visited regularly.  The location should not be prone to standing or flowing water during rain events or to drifting snow.  If the location appears unreasonable, involve the designer and utility company as soon as possible, since moving a power service often means redesigning the lighting circuits.

Verify that the Contractor has been in touch with the utility company and is aware of any utility company requirements which may differ from the requirements of the Contract Documents.

Verify that the photocell is facing the north sky, unless otherwise stipulated by the plan, and that no artificial lighting source is disrupting its proper operation.

Verify that the conduits are neatly routed and fastened securely in place.

Verify that enclosures are securely mounted.

Verify that enclosure covers are in place and fasteners for the covers have had anti-seize or grease worked into the threads.

Verify that moving parts of the switch gear have been lubricated and operate smoothly.

Verify that no debris has been left in enclosures and that the wiring in each enclosure is neat, orderly, and tied into place where appropriate.

Grounding (625.16)

The conducting portions of those items which contain electrical conductors are to be connected to each other and to earth electrodes to lessen the chance of injury and damage from unwanted electrical currents.  Connecting the various conducting portions together to form a continuous path for the flow of stray electrical currents, often referred to as bonding in ODOT’s projects, is generally incidental to the construction.  Installation of the earth electrodes and the connection of the conducting portions to those electrodes is often referred to as grounding, and in ODOT’s project’s payment is somewhat related to the electrodes installed.

Ground Rods

Verify that the specified ground rods have been installed.  When additional rods have been added to lower the resistance, verify that the installation of each rod was approved prior to its installation. 

Verify that the connection between the ground rod and the grounding cable is an exothermic weld.  When additional rods have been added to reduce the resistance, verify that the additional connections are exothermic welds.

The normal ground rod item is for one rod, driven into earth, and the lead between the rod and the first connection and associated connections.  The earth resistance is then checked.  When said resistance exceeds the specified limit, an additional rod is to be driven and connected to the first. The earth resistance of the pair is then checked. The process is repeated until the resistance of the group is lower than the specified limit.  Payment is then made for each rod installed at the “per rod price.” 

ODOT has reserved the right to approve the use of each additional rod before it is installed and may decline to install additional rods, thereby stopping the process at any point.  When ODOT stops the installation of additional rods, it may decide to take another course of action to lower the earth resistance.  If no additional action is taken, then by default, the earth resistance becomes acceptable as it stands.

Exothermic Welds

An exothermic weld often has a rougher surface texture on the weld metal than one may be used to seeing, but the weld is not to have other signs of a poor quality weld, such as porosity, cratering, cracking, or undercutting.

Structure Grounding

Verify that each grounding electrode is acceptable before structure construction makes modification of the electrode, or the installation of additional electrodes, impractical.  Remember, if some of the electrodes are driven rods that such rods are incidental to the structure grounding system, not separate items.  However, if due to high resistance, additional rods are driven, those rods are not incidental to the structure grounding system.

Verify that the necessary bonding jumpers are in place and functioning correctly before structure construction makes the installation of additional jumpers impractical.

Structures present special needs.  Not only is it impractical to have a separate ground rod for each light pole or similar item mounted upon the structure, but there are also elements of the structure itself that need grounding.  The normal practice is to use bonding jumpers to connect all exposed metal items together and therefore to the several electrodes which frequently utilize the main conducting portions of the structure as the main grounding buss.  This means that electrodes are often under footers and bonding jumpers are frequently embedded in the structure.  If something is left out or does not function as intended, and it is not discovered until the final stages of construction, the grounding can become expensive, unsightly, and less than desired.  Unfortunately, structure designers all too often include little in the way of specific details for the structure grounding.  Therefore, it is imperative to constantly think ahead to fully understand where each electrode and jumper is to be located and to verify that it is in place and functions correctly at each stage.

Bonding along Circuits

Verify that all of the conducting items which contain the conductors of each circuit are bonded to form a continuous path back to the source of the circuit.

At light poles, verify that metal conduits entering the base of the pole are bonded to the pole.

At pull boxes, verify that the metal conduits entering the pull box are bonded together and the metal lid and lid frame are bonded to the metal conduits.

At junction boxes, verify that the metal conduits entering the junction box are bonded to the box.

At the expansion and deflection joints in conduits of conducting materials, verify that a bonding strap has been install across the joint.

When non-conducting conduit or duct is used, verify that a grounding conductor has been installed to provide for the continuous grounding path.

Wiring and Cabling (625.17)

Field wiring of highway lighting circuits is broken into three types.

Pole and Bracket Cable

Pole and bracket cable is the insulated, single conductor used in a light pole (but not in a light tower) to connect from the distribution cable, up the pole, and out the bracket arm to the light fixture. In a tower, the electrical wiring from the base of the tower to the luminaires is a component of the lowering device.

Verify that each run of cable is of the size and type specified. The wire size and insulation are to be indelibly marked on the insulating jacket at frequent intervals along the length of the cable.

Verify that each run of cable is installed in a continuous piece without inline splices between the terminations shown on the plan.

Verify that the insulating jacket wasn’t nicked, nor portions shaved away, as the cable was pulled into place.

Verify that the cable was not stretched as it was pulled into place.  If the cable can be pulled back and forth by hand enough to move both ends, stretching probably did not occur.

Verify that a cable support was installed at the upper end of the vertical run of cable up the pole.

Verify that there is enough length on each end of the run for the cable to be routed properly to its termination and still remain slack.

Distribution Cable

Distribution cable is the insulated, single conductor used to construct lighting circuits from the control equipment of the power service to the disconnect kits of a light pole, the terminal block of a light tower, or the disconnect switch for underpass or sign lighting.

Verify that each run of distribution cable is of the size and type specified. The wire size and insulation are to be indelibly marked on the insulating jacket at frequent intervals along the length of the cable.

Verify that each run of cable is installed in a continuous piece without inline splices between the terminations shown on the plan.

Verify that the insulating jacket wasn’t nicked, nor portions shaved away, as the cable was pulled into place.

Verify that the cable was not stretched as it was pulled into place.  If the cable can be pulled back and forth by hand enough to move both ends, stretching probably did not occur.  Unfortunately, for the larger wire sizes and the longer runs commonly encountered in highway lighting circuits, the cable cannot be pulled by hand.  The most common indication of stretching is when the length of pulling lead exiting the raceway is greater than the length of cable entering the raceway, or the pulling forces are greater than normally encountered, both of which are not easily detected by anyone other than experienced installers.

Verify that there is enough length on each end of the run for the cable to be routed properly to its termination and still remain slack.

All cables shall be labeled in accessible enclosures (pull boxes, hand holes, transformer base, device housing, etc.).  A minimum of 5 feet (1.5 m) of extra cable shall be provided for each conductor at all terminal points.

Duct-Cable

Duct-cable consists of insulated conductors, of the type used for distribution cable, installed into a duct and shipped as an assembly to the project. It is used in place of conduit and distribution cable to speed the installation of underground circuits.

Verify that the temperature of the duct-cable was above 32 °F (0 °C) throughout the installation process.

It is permissible to install duct-cable when the outdoor air temperature is actually below those temperatures, but the Contractor must obtain authorization from the Engineer.  The Contractor shall submit, in writing, his method of heating the duct-cable and maintaining the duct-cable at a uniform temperature throughout the installation process.  To ensure that the duct-cable is heated uniformly, the heating process shall keep the temperature of the duct-cable above 32 °F (0 °C) for a minimum of 24 hours prior to installation.  Under conditions, such as the preceding, where the temperature of the duct-cable can be expected to vary widely during the installation process, the expansion and contraction of the duct-cable must be taken into consideration.  Typically, the duct-cable length will decrease or increase 1 foot per 1,000 feet (0.3 m per 300 m) for each 10 °F (5.6 °C) decrease or increase in temperature.

Verify that the duct of the installed duct-cable extends out of any conduit sleeve through which it passes enough to allow for the expansion and contraction in the duct due to seasonal changes in temperature.  Typically a projection of 2 to 3 inches (50 to 75 mm) is appropriate at the usual installation temperatures for the lengths of run typical in ODOTs installations.

As received on the reel from the manufacturer, it will appear that the cables inside the duct and the duct are equal in length, but in reality the cables are shorter than the duct.  In order to reel the assembly onto the shipping spool, both the cables and the duct were anchored to the spool. As the duct cable assembly is unrolled from the shipping spool, the cables will be drawn into the duct resulting in empty duct at the start of the run.  For the assemblies typically used in ODOTs projects, leaving 25 feet (7.6 m) of duct for each 1,000 feet (300 m) of run to be installed, in addition to that required as slack for connections at the start of the run, will compensate for this.  At the end of the run, only the slack amount for connections is required.

Verify that the insulating jacket of each cable within the duct has not been damaged when the duct was stripped to allow the connections to be made.  Often the length of duct to be stripped is such that no protection can be slid over the cables and into the end of the duct, which means that the cables within are saved from damage only by the skill of the person stripping the duct.

When a duct cable assembly has been passed through a conduit sleeve, verify that the duct has been sealed to each end of the sleeve by means of a molded boot or wrapped sealing pad.

Verify that the seal installed between the cables and the duct is installed in the same location and in the same manner as outlined under the installation of distribution cable into conduits.

Verify that there is enough length on each end of the run for each cable to be routed properly to its termination and still remain slack.

Conductor Identification

At each access point (pole base, pull box, junction box, switch gear enclosure, etc.) each conductor of each run of the field wiring (pole and bracket cable, distribution cable, duct-cable) of each circuit is to be identified by applying a tag to the conductor indelibly marked to indicate the circuit and the use of that conductor within the circuit.

Connections (625.18)

This covers the connection of the field installed wire and cable to other such wire and cable and to the various items of equipment.

Sizing Conductor to Device Terminal

When the circuit conductor is of a larger size than the device terminals can accommodate, verify that the connection has been made by splicing a short piece of smaller wire onto the end of the large wire and then connecting the smaller wire to the device terminal.  The smaller wire is normally identical to the larger wire in all aspects except for size.  The smaller wire must be large enough to carry the current that the circuit protection will allow.  It is not acceptable to cut back some of the strands of a conductor, so that the remaining stranded will fit into the terminal.

Crimped Compression Connections

Verify that the die in the compression tool was for the connector applied. The connector is sized to match the wire to which it was applied and the tool used was of a type that did not release the connector from the die once compression started until full compression was achieved.

Pull-Apart and Bolted Connections

Verify that the internal connector is properly applied to the conductors.

Verify that the insulating cover was cut to proper step for a snug fit over the insulation on each entry to the housing.

Verify that the internal parts are all present in good condition and are fully seated into the housing.

Verify that the male half of the housing is a snug fit and fully inserted into the female half of the housing.

Verify that a thin coating of the kit manufacturer’s approved, non-conducting grease has been used at the joint between the two halves of the housing, between the housing and each cable entering the housing, and on other internal parts, as show in the manufacturer’s instruction, which allow the parts to slide smoothly into place and help seal out water.

Verify that there are no sharp bends in each cable where the cable enters the housing sufficient to cause the housing to pull away from the insulating jacket on the cable.

When the kit is to contain a fuse, verify that the fuse is of the proper ampacity.

Where the kit contains bolted connections, verify that the connections have been properly tightened before the housing was closed.

Verify that there is sufficient slack in the cables being connected to permit bringing connector kits outside of the pole, transformer base or junction box in which it is housed for servicing.

Unfused Permanent Connections

Verify that the internal connection is via a proper crimp compression connector.

Verify that the mold surrounding the connection is completely filled with resin.

Verify that the connection is positioned within the mold such that the resin properly surrounds the connection.

Verify that there are no voids in the resin.

Verify that no fillers have been used.

Verify that the resin has properly set.

Testing of Installation (625.19)

There are a number of tests normally utilized to ascertain that the lighting installation has been well constructed and is in good operational order. For a particular test to have meaning it must be properly conducted and the results properly interpreted.

Verify that the equipment used to conduct the test is in working order and calibration.

Grounding Electrodes and Grounding Systems (625.19.B)

Verify that each specific grounding electrode meets the requirements of the earth resistance test. 

The first key to conducting a successful test of a grounding electrode is to understand what constitutes the electrode.  A single driven rod is an electrode.  When that rod fails the earth resistance test and another rod is added, the electrode then becomes both rods together.  However, in the case of a light tower where two rods are typically specified, the initial electrode is the two rods together rather than each rod separately.  In structure grounding, the cluster of driven piles at the end of a pier footer should be considered as a single electrode, with the cluster at the other end of that same footer considered as a separate electrode.  A continuous grid of mesh, bars, or cables laid beneath a footer is one electrode, but separate grids under different portions of the same footer are separate electrodes.  Wires buried in a radial pattern from a single pole constitute an electrode.

The second key to successful ground resistance is to understand the limitations of the various test instruments and procedures.  The chosen procedure must be appropriate for both the electrode under test and the conditions in which the electrode is installed and the instrument must be capable of producing valid results for the situation at hand.

Circuit Continuity (625.19.C)

The key to the proper checking of circuit continuity is to remember the objective and to test one conductor at a time.  The objective is to see that the conductor is connected to the desired device point and the conductor has not been connected to any other devices.  The difficulty is that the devices are scattered over a large area, thus, requiring the other conductors of the same circuit to be used as returns for the test signal.  For the test to be of use, the testing must start at one node in the circuit and test all connections along an isolated link from that node. Additional nodes and links are then added one at a time and the continuity of the conductors rechecked until the entire circuit has been verified.

Cable Insulation (625.19.D)

This test is designed to verify that the insulation of each conductor in the circuit, and permanent and bolted connections in that conductor, are in good conditions to impress a much higher than normal voltage on the conductor using the change in leakage current over time. Care must be used not to impress the test voltage on devices normally connected by the circuit since the devices would probably be damaged.  Since the other conductors in the circuit must often be used as the return path, it is necessary to use care to ensure that other conductors are not damaged while serving as signal returns and careful interpretation of the results to determine whether the leakage is from a conductor failing the test or from a failure in the return path.

Lowering Device Operation (625.19.E)

This test is simply repeated operation of the lowering device on a light tower to verify that is operates smoothly and correctly throughout its full range cycle of motions.

System Performance (625.19.F)

The test uses the concept, “infant mortality,” to determine if the equipment is likely to operate satisfactorily throughout the projected life of the installation.  The concept is that the equipment is most likely to fail from manufacturing defects and installation in the first few hours of use, and once these hours are past, it is likely to run the rest of its life with only normal maintenance.  In conducting the test, it is important to recognize the significance of each component malfunction encountered and to properly interpret whether the malfunction indicates a need to extend the test period. 

Information to Maintaining Agency

Ensure that each maintaining agency receives the documents pertinent to the maintenance and operation of the lighting units for which it is responsible.  Typically included are:

1.        A copy of the plan marked to show any changes made during the construction.

2.        A copy of each certified shop drawing or catalog cut.

3.        A copy of each instruction or parts manual supplied by each manufacturer.

Documentation Requirements

1.        Luminaires.

a.        Luminaire has the distribution, lamp, and aiming stipulated in the Contract Documents.

b.        Luminaire has been “leveled.”

2.        Supports.

a.        Support is the one stipulated for that location by the Contract Documents.

b.        Support is comprised of the correct components according to the certified shop drawings.

3.        Pull boxes.

a.        Pull box is the size and type stipulated for that location by the Contract Documents.

b.        If supplied under plant sampling and testing program, it has a TE-24.

c.        Drain is documented on form CA-P-1.

4.        Conduit.

a.        Conduit is the size stipulated for that location by the Contract Documents.

b.        Conduit is of the material stipulated for that location by the Contract Documents.

c.        Measure length installed.

5.        Trench.

a.        Location and depth is as stipulated by the Contract Documents.

b.        There are no sharp rocks in backfill adjacent to duct.

c.        Backfill is placed in 4 inch (100 mm) lifts and mechanically tamped.

d.        Measure length installed.

6.        Grounding electrodes.

a.        Electrode is installed as stipulated for that location by the Contract Documents.

b.        Grounding conductor connected to ground rod with exothermic weld.

c.        Document ground resistance.

7.        Wire and Cable.

a.        Wire size and insulation is as stipulated for that location by the Contract Documents.

b.        Measure length installed.

626 Barrier Reflectors

General

This information is intended to serve as a guide for construction personnel where the Contractor furnishes and installs barrier reflectors.  It may also be useful for maintenance personnel performing the same functions.  Inspection procedures are outlined.  This information points out the various important features and references the applicable specification or standard drawing.

Materials (626.02)

Make sure that all barrier reflectors used on a project are approved and listed on the Qualified Product List at the following website:

Item 726.01 Barrier Reflector Type A & B

                http://www.odotonline.org/materialsmanagement/qpl.asp?specref=726.01

Installation (626.04)

1.        Ensure that the color of the reflector matches the color of the nearest edge line.

2.        Ensure Type A and A2 guardrail blockout reflectors are installed on the side of blockout away from traffic.

3.        Ensure that the guardrail blockout reflectors are installed on the side of the blockout nearest the edge of the pavement.

4.        Ensure that the guardrail blockout reflectors are installed so that the reflective surface is above the guardrail.

5.        Ensure Type B and B2 are installed with the top of the barrier reflector 26 inches (650 mm) above the near edge of pavement, except that the top of the barrier reflector is at least 3 inches (75 mm) below the top of the concrete barrier.

6.        Ensure that the barrier reflector does not extend further than 5 inches (125 mm) in a horizontal direction toward the traffic lanes.

7.        Ensure that loose concrete, rust, dirt, and other loose materials are removed from the surface of the concrete barrier or guard rail using a wire brush. Apply adhesive to clean and moisture-free surface according to manufacturer’s recommendations.

Figure 626.A – Barrier Reflector Type A and A2

Figure 626.B – Barrier Reflector Type B and B2

Documentation Requirements - 626 Barrier Reflectors

1.        Document on CA-D-3A that installation performed as per 626.04.

2.        Document on CA-D-3A that material and products based on certified test data and all drawings.

3.        Document on CA-D-3A the types of barrier reflector for pay.

630 Traffic Signs and Sign Supports

Description (630.01)

This information is intended to serve as a guide for construction personnel where the Contractor furnishes and installs traffic control devices and appurtenances. It may also be useful for maintenance personnel performing the same functions. Inspection procedures for various types of traffic control devices are outlined, mainly in the form of checklists to assist project personnel in performing their duties. This information points out the various important features of each device and references the applicable specification or standard drawing. Illustrations are used for easy recognition of the device or feature being discussed.

Sign Service

Sign service shall comply with SCDs TC-32.10 and TC-32.11 and the plans. Additional information is provided in TEM Section 240-7.2 and C&MS Item 631.04. It consists of cable and equipment to provide a complete electrical service from either an underground source or an overhead direct drop to separately furnished disconnect switch with enclosure. The equipment could include a weatherhead, a conduit riser with necessary fittings, attachment clamps, and cable.  A thorough review of the plans should be made to determine the specific requirements of the maintaining agency for sign service.

When required, an electric meter base will be furnished by the applicable utility and installed by the Contractor as part of the sign service work.

The sign service shall terminate at the meter base if used; otherwise, termination shall be at the switch enclosure. Sign service may be:

1.        Direct drop by means of a weatherhead and conduit riser routed to the switch enclosure.

2.        Underground conduit and the pole interior to the enclosure.

3.        Underground and structure-attached conduit to the enclosure (for overpass mounted signs).

The conduit riser shall comply with Item 725 and the plans, and the weatherhead shall be threaded aluminum or galvanized ferrous metal 732.16.

The disconnect switch shall be a single-throw safety switch which meets the voltage and capacity requirements of the plans. The enclosure shall be a NEMA Type 4 ICS 1-110.15 with sufficient volume to accommodate an internal transformer when specified. The enclosure shall contain a solid neutral bar.

A ground wire shall be used as shown on SCDs TC-32.10 and TC-32.11 leading to a ground rod installed in accordance with TEM Section 240-7.3.

Sign Fabrication (630.04)

General

Signs should be inspected when received on the job site if possible, but certainly prior to erection.

The signs should be inspected for conformance with the plans, certified shop drawings, catalog cuts, and material specifications.

Flatsheet signs are typically of aluminum sheet cut into geometric shapes of the size specified.

Dimensions and thickness are to be as shown on SCDs TC-52.10 and TC-52.20. Bolt holes are to be drilled or punched (630.04).

Extrusheet signs are fabricated of aluminum sheet and extrusions, joined by spot welding and assembled by bolts (SCD TC-51.11). As an alternative, panels extruded in a single operation may be used (SCD TC-51.12). Extruded panels and spot welded panels shall not be used in the same sign. There shall be no appreciable deviation from flatness on the face of an assembled sign.

Overlay signs are of aluminum sheet of the specified thickness and used to cover the legend of extrusheet signs. Signs with overlays should be checked for any loose rivets holding the overlay sign.

All signs shall be reflectorized by being covered with the appropriate grade of sheeting. The sheeting shall be of the correct color, firmly attached, and free of tears, wrinkles, blisters, or blemishes.

Sign legend shall be in accordance with the plans, certified shop drawings, and the OMUTCD.

The type of copy on extrusheet signs shall be as shown on the certified shop drawings. Available types of copy are listed in TEM Table 297-6.

All signs shall be identified on the reverse side by decals as described in 630.

Extrusheet signs shall also to be identified by information in a detachable form on the back (see Item 630.04).

Sign Copy

TEM Table 297-6 provides information about the sign copy used, type, material used, design features, etc.

Sign Identification Decals

All signs shall be identified on the reverse side by decals of Type F white reflective sheeting (730.18) with silk screened numerals. Information shall be coded by screened-on or punched-out numerals before decal application and shall include sheeting manufacturer and year of sign fabrication. At the time of erection, month and year of erection shall be scratched out by the Contractor. This procedure is described in 630.04, which also contains an illustration of the decal. Decals for overlay signs may be on the front surface.

The following codes shall be used on the decals to identify the manufacturer of the sheeting.

0 - Avery Dennison

1 - Minnesota Mining and Manufacturing Company (3-M)

2 - Sakai Trading-New York, Inc.

3 - Nippon Carbide Industries (USA)

4 - Morgan Adhesives Company

5 - American Decal and Manufacturing Company

6 - Stimsonite Corporation

7 - Reflexite North America

Foundations (630.05)

Staking

Sign support foundations shall be located so the sign face is at a right angle to the roadway lanes served, unless the plans specify otherwise. An example of an exception is the W1-6 Large Arrow sign (black arrow on yellow background), which is located as shown in TEM Figure 298-24.

Foundations should be staked by the Contractor in accordance with the locations shown on the plans.

The stakeout locations should be checked for:

1.        The presence of obstructions which could restrict motorists' proper visibility of the sign from the point where they are expected to read the sign. Curved roadway locations should especially be checked.

2.        Obvious conflicts with overhead power lines or other utilities. There should be available a proper safe clearance from overhead lines for construction operations, in compliance with the National Electric Safety Code and any local codes.

3.        Possible conflict with underground facilities.

Foundation locations may be adjusted when necessary to overcome difficulties such as those shown in TEM Figure 298-24 and discussed herein with the concurrence of the project engineer. Adjustment should not violate minimum clearance dimensions as shown on SCDs TC-42.10 and TC-42.20 and the OMUTCD.

Excavation

Foundations shall be placed only in undisturbed soil or compacted embankment, and excavation shall be by an earth auger of the specified diameter to the specified depth. See TEM Figure 298-25 for a diagram of a foundation excavation.

If a minor cave-in should occur, the Contractor may continue excavation using an increased diameter or using sleeving, casing, or other method approved by the Project Engineer. The foundation concrete will be measured as determined from plan dimensions. The Contractor shall remove all extraneous material from the excavation before concrete placement.  When subsurface obstructions are encountered, permission may be granted by the Project Engineer to replace the excavated material and relocate the foundation.  When bedrock is encountered, the portion of the specified foundation depth within the bedrock may be reduced as much as 50 percent.

Placement

Anchor bolts and conduit ells shall be of the correct size and furnished with the support. At least one 2 inch (51 millimeters) minimum conduit ell shall be furnished and capped if unused. Anchor bolts, conduit ells, and EMT (Electric Metallic Tubing) shall be oriented in the foundation according to the plans, conduit runs, and ground rod location.  All anchor bolts shall be provided with standard steel hex nuts, leveling nuts, and plain washers.  The nuts shall be capable of developing the full strength of the anchor bolts.  Reinforcing bars, tie loops, and tie bars shall be of the correct size and arranged with the anchor bolts into cages according to the applicable SCD TC-21.10 or SCD TC-21.20.  A special foundation design will be required when soil with a load bearing capacity of less than 2,000 pounds per square foot (9700 kg/m²) is encountered.

Anchor bolts shall be vertical with their ends projecting the correct distance above the foundation surface in compliance with the plans.  When the distance the anchor bolts project above the foundation surface is not specified, a rule of thumb is four times the bolt diameter.  The anchor bolts shall be tied to the cage tie bars according to standard details.

The rebar cage shall be supported 3 to 4 inches (75 to 100 millimeters) above the bottom of the excavation by a piece of concrete block or similar material. The cage shall be positioned with a clearance of 3 inches (75 millimeters) from the excavation wall by similar blocking so that after concrete placement a full thickness cover is assured.  A template and/or frame shall be used to rigidly hold the anchor bolts and conduit ells in the specified pattern during concrete placement. A form shall be oriented according to the plans to shape the foundation into a square from the surface or grade shown to a nominal 6 inches (150 millimeters) below ground line.  The template and form may be combined. Gaps of 6 inches (150 millimeters) or less between the foundation and adjacent paved surfaces shall be eliminated by increasing the formed foundation.

Water encountered in the foundation excavation shall be pumped out before concrete placement.

If this is not feasible, concrete should be placed by the tremie-tube method.

Concrete conforming to Item 499 and Item 511 shall be placed and vibrated to eliminate voids. Care should be exercised during vibrating to avoid disturbing the anchor bolts, conduit ells, and reinforcing cage.

Forms may be removed as soon as the concrete has hardened sufficiently so as not to be susceptible to damage, 511.16.

Minor earth caving external to the hole, which may have occurred during excavation using sleeving or casing should be corrected after concrete placement by backfilling and tamping in accordance with 203.

Joint filler complying with 705.03 shall be placed between the formed foundation and adjacent paved surfaces.

Supports and poles may be erected, signs installed, and span wire load applied only after the concrete has aged sufficiently to be in compliance with 630.

Curing and Loading

Curing and loading of concrete for traffic control devices shall comply with 511.17.

Concrete for foundations of sign supports shall be cured, have bracing removed, and be loaded only when the concrete has achieved the age shown below:

Age of Concrete in Days

Without Beam Test

With Beam Test **

Curing

7

5

Removing Bracing

7

3

Loading*

14

7

* No load shall be applied or other work done that will damage new concrete or interfere with its curing.

** Beam test specimens shall be poured from the same batch, immediately before, during, or after foundation pour. Specimen configuration shall be to ODOT requirements. Specimens when tested shall have at least an average modulus of rupture for two tests of no less than 650 pounds per square inch (4.5 MPa).

Sign Supports (630.06)

General

Various general aspects of overhead sign supports are addressed in this section. TEM Table 297-7 provides an overall summary of the structure types, allowable sign area on each, and the span or arm length.

Pole and Support Inspection

This inspection checklist covers the general features of strain poles, mast arm type signal supports, and overhead sign supports. Features pertaining only to specific pole or support types will be found in the sections of this manual covering exclusively those poles or supports.

1.        When poles and supports of the combination type are specified, they are to provide extra length for a highway lighting function, and welded-on bracket arm plate(s) complying with SCD HL- 10.12 or SCD HL-10.11 for attachment of a separately furnished luminaire arm. An upper handhole and an additional internal J-hook are to be furnished.

Figure 630.A

2.        Supports may be of an alternate design utilizing all non-tapered tubing structural members.

3.        If possible, poles and supports should be inspected when received, but certainly prior to erection.

4.        General dimensions should be checked first, including pole length, base diameter, top diameter, and wall thickness. Similar mast arm dimensions should also be checked. Wall thickness is most easily measured with calipers at the end. Caps on poles may have to be removed.

5.        Orientations of the various appurtenances should be checked against the plan’s orientation diagram if such is available; otherwise, orientations may be determined from certified shop drawings and the intersection drawing.

6.        Base plate dimensions should be checked including thickness, bolt circle diameter, and bolt hole size. Base plates may be plate or cast steel according to 730.04.

7.        A handhole with ground lug is to be furnished, with a cover plate complying with 730.05 and a stainless steel chain complying with 730.10.

8.        Blind half-couplings shall be provided where required. Sharp edges shall be rounded to prevent damage to cable or wires. Blind half-couplings shall be plugged when not in use. Couplings may be for signal or interconnect cable entrance or for attaching supports for traffic control equipment and for hubs for controller cabinets. Entrance couplings shall be threaded for use with threaded weatherheads.

9.        An internal J-hook shall be furnished and located as indicated on the plans.

10.     A pole cap conforming with 730.06 shall be furnished and in place before final inspection.

11.     An arm cap conforming with 730.07 shall be furnished for chords or mast arms.

12.     All strain poles and overhead sign and signal supports shall be grounded, even if no power is available.

13.     Welding and galvanizing shall be inspected in accordance with 630.

14.     Supports are to include sign brackets, U-bolts, and clamps. When required by the plans, supports are to include luminaire support arms, bracing rods, other necessary structural members, and signal hanger clamps with clevis.

15.     The correct number and size of anchor bolts and conduit ells shall be furnished for placement in the foundation.

16.     Anchor bolt diameter and length shall be according to the plans and SCD TC-21.10 or TC- 21.20. Anchor bolt ends may have an L-bend or be fitted with a tapped steel plate. Threaded ends shall not to be damaged and shall be galvanized at least 2 inches (50 millimeters) beyond the threads. The galvanizing should be in good condition, and absent or damaged galvanizing should be repaired by the application of two coats of zinc-rich paint. Galvanizing thickness should permit the turning of nuts by a wrench without difficulty. Loose rust on anchor bolts should be removed.

17.     All anchor bolts shall be provided with standard steel hex nuts, leveling nuts, and plain washers. The nuts are to be able to develop the full strength of the anchor bolts.

Inspection of Welds

All welds of supports shall be inspected visually, as soon as possible, following support delivery. Welds should be inspected for flaws and imperfections under good lighting conditions using a magnifying glass as necessary. Evidence of any of the following faults or other imperfections, such as warping and misalignment may be cause for rejection of the support. The following features of welds should be checked:

1.        A check should be made for the actual presence of all welds called for by the certified shop drawings and standard drawings.

2.        Welds on tapered tubes, pipe, or structural shapes shall be continuous around the joint. Welds requiring terminations shall be of the correct length.

3.        Welds shall not exhibit cracks or discontinuities in base metal or weld material and shall not show evidence of porosity, which shows up as pitting or pinholes. The galvanizing layer may cover such flaws, but their existence should be checked.

4.        Welds shall be full cross-sections without excessive concavity or convexity. Required weld terminations shall be filled to full section without depressions or craters.

5.        There should be no evidence of undercut, a condition where a shallow groove is melted into the base metal adjacent to a weld and left unfilled by weld metal.

6.        Base plates shall be welded to two ply poles with AWS prequalified welds in conformance with 730.04.

7.        Arm attachment plates shall be welded inside and outside with fillet welds. Each fillet weld shall be equal to the wall thickness of the respective tubing.

Inspection of Galvanizing

The galvanizing cover of supports shall be inspected visually, as soon as possible, following delivery. The galvanizing should be inspected externally and internally for flaws and imperfections in daylight or strong artificial light. In accordance with 513.26, supports shall be loaded, transported, unloaded, stored, and erected in a manner to avoid damage to any feature including the galvanizing. Supports stored in the field should be kept off the ground to prevent the galvanizing from contacting water, which may result in a premature oxidation condition. The galvanizing should have the appearance of a uniform application. Supports should be checked for assurance that the following flaws or imperfections do not exist:

1.        Loose or bare spots in the galvanizing where improper preparation has prevented metal adherence in the molten zinc bath. Poles should be rejected if the point of a penknife can flake off the galvanizing layer.

2.        General overall roughness, a symptom of over-pickling or of excess zinc bath temperature and/or immersion time.

3.        Pimples, due to entrapped bath scum particles.

4.        Blisters, due to hydrogen gas absorbed during pickling and coming out at the time of galvanizing.

5.        Flux inclusions, picked up from the top of the bath when dipping and burnt-on during immersion.

6.        Ash, usually in course lumps picked up from the top of the bath.

7.        Patches of dull gray coating due to the slow cooling of heavier cross-sections of supports after immersion.

8.        Excess zinc lumps or runs due to delayed molten metal run-off from surface discontinuities, such as joints, seams, or holes.

9.        Rust stains due to the weeping of impurities from the pickling process at seams and folds.

Excessive galvanizing faults and imperfections combined with general poor workmanship may be cause for rejection of the support. Gross imperfections may lead to the suspicion of inadequate protective cover which may require inspection with a magnetic instrument. Items 1 through 6 may be cause for rejection. Items 7 through 9, if extreme, may be cause for rejection because of poor appearance, even if the protection of the support is not affected.

After erection, supports should be given a final inspection for any damage to the galvanizing due to improper handling in the erection process. Damage due to slings, etc., which is more serious than superficial brightening, is to be repaired by the Contractor with the application of two coats of zinc-rich paint.

Weight of Supports

TEM Tables 297-8a through 297-8f provide information on the weight of various overhead sign supports. For all structures, the weight of the pipe support has been given where pipe has been frequently used in place of tapered tubes. In general, the tapered tube support will be lighter than the pipe support. The support numbers listed may be preceded by I-129, 815, 844, or other designation instead of TC.

For estimating purposes, a 10 x 10 foot (3.0 x 3.0 meter) sign, excluding the sign lighting, weighs approximately 250 pounds (113 kilograms).

Assembly and Erection Procedure

Erection procedures pertaining to specific pole or support types will be found in the sections of this manual devoted exclusively to those poles or supports. In general, the following assembly and erection procedure applies:

1.        To minimize erection time and the hazard to workers and road users where traffic is maintained, supports should be erected with mast arms attached, and horizontal sign support members (over the roadway) should be prewired for lighted signs or other traffic control devices. See the notes in plans for traffic maintenance requirements when span-type sign support members are erected.

2.        Support components shall be assembled with their threaded fasteners tightened in accordance with 630.06. Fasteners 1/2 inch (13 millimeters) or greater shall have anaerobic adhesive applied to the threads according to the manufacturer’s recommendations. Nuts shall be tightened by the turn-of-the-nut method.

3.        The turn-of-the-nut method shall be in accordance with 513.20. Nuts shall be made snug tight by the effort of a person using an ordinary spud wrench followed by an additional 1/12 to 1/6 turn.

4.        Leveling nuts shall be placed on the anchor bolts, initially clearing the foundation surface by at least 1/4 inch (6 millimeters) and forming a horizontal plane.

Figure 630.B

5.        Poles or supports shall be raised into position with equipment of adequate lifting capacity and used in a manner preventing damage to attached appurtenances (signs, brackets, luminaries, etc.) and to the galvanizing. The weight of poles or supports is given in TEM Tables 297-8a through 297-8f for the use of the Contractor in the erection procedure.

6.        With the pole or support’s base plate resting on the leveling nuts, the plain washers and anchor nuts shall be placed on the anchor bolts, the support plumbed in a vertical position or raked, and anchor nuts given a preliminary tightening.

7.        After any necessary leveling, nut adjustments are made to ensure that supports are essentially vertical after attachment of signs, sign lighting equipment, or signals. The anchor nuts shall have anaerobic adhesive applied and be tightened in accordance with the instructions for assembling fasteners given in the foregoing paragraphs, 2 and 3.

8.        Anchor nuts are not to be covered with bolt covers or a cover base regardless of support location (Item 630.06B).

9.        Poles or supports which are prewired before erection should be checked to determine if the erection procedure has disturbed the wiring. Wire for lighted signs should be supported by looping wire over the J-hook in the vertical support member (Item 631.05). Cable supported by cable support assemblies should be checked to determine if the sling is over the J-hook and if the adjustment is proper to eliminate strain on the cable jacket.

Overhead Sign Supports by Type

General

The previous section addressed general assembly and erection guidelines for strain poles and supports. The following sections provide additional information specific to various types of supports. For the most part, the information is provided in checklist format.

Ground-Mounted Sign Supports (630.06.A)

General

This section provides additional information, generally in the form of checklists, about various ground-mounted supports. TEM Section 221 addresses general guidelines about sign supports and TEM Section 240-5 provides additional design information about ground-mounted supports.

Posts

1.        Ground-mounted sign supports of the post type shall be U-channels or square posts of the number specified and shown on SCD TC-41.20.

2.        Post lengths appearing on the plans are approximate and the Contractor is responsible for determining the exact length of required posts before cutting to length (630.06A).

3.        No. 4 U-channel posts consist of two No. 2 posts bolted back-to-back. No. 6 U-channel posts consist of two No. 3 posts bolted back-to-back. Back-to-back posts are assembled by 5/16-inch (8 millimeters) steel bolts, lock-washers, and nuts on 4-inch (100 millimeters) centers below the ground line and 16 inch (400 millimeters) centers above the ground line.  No. 4 and No. 6 U-channel posts cannot be installed in exposed locations.

4.        Posts should have a line of paint 48 inches (1.20 meters) from the end, which will be in the earth. The mark when driven to a distance of 6 inches (150 millimeters) above the ground indicates a post driven to the proper depth.

5.        If it is necessary to cut posts to correct length in the field, the cut end should be covered with two coats of zinc-rich paint and the cut end driven in the earth or embedded when required (except for back-to-back posts).

6.        Posts shall yield when hit and shall be driven to a depth of 42 inches (1.05 meters). Posts are typically not to be embedded in concrete unless specified in the plans or ordered by the Project Engineer to overcome problems, such as adverse soil conditions or prevalent bedrock close to the surface. The driven depth has been established to ensure best yielding characteristics. Deeper depths are not beneficial in this regard.

7.        Caution shall be used when driving posts in areas of buried cable.

8.        Posts shall not to be driven in drainage ditches.

9.        Posts shall be installed vertically and at right angles to the edge of pavement, unless otherwise required. Exceptions may be NO PARKING signs and STOP signs located at intersections with curved approaches. In this situation, STOP signs should be placed perpendicular to a line from the viewing point where they are normally recognized and stopping action would begin.

10.     Posts shall be driven without bending, distortion, or end mutilation. Mutilation may be prevented by the use of a driving cap. Posts should be checked to see if the paint mark is 6 inches (150 millimeters) out of the ground after driving.

11.     Posts located in paved areas shall be driven through a hole provided by sleeving or core drilling. After driving, the hole shall be patched with asphalt concrete or approved bituminous material.

12.     At locations where posts cannot be driven, the post may be moved at no additional cost to ODOT, when approved by the Project Engineer.

13.     Typical vertical and horizontal clearances of signs are shown on SCDs TC-42.10 and TC- 42.20.

“One Way” Sign Supports

Square posts, which are capable of supporting signs at right angles to other signs on the post, are designated as “One-Way” sign supports for the most common application. This is shown on SCD TC-41.50.

Standard Beams

1.        Ground-mounted sign supports of the non-breakaway beam type shall be rolled steel, wide flange sections of the size, and weight specified (from the list on SCD TC-41.10). Non-breakaway beams shall be protected by guardrail or concrete barrier installed for another purpose. Inspection of beams of the breakaway type is covered in 630.

2.        Beam lengths appearing on the plans are approximate and the Contractor is responsible for determining the exact length of required beams before fabrication (630.06 A).

3.        Galvanizing shall be inspected in accordance with 630.

4.        Beams shall be embedded in a concrete foundation in accordance with SCD TC-41.10.

5.        Beams shall be raised into position with equipment of adequate lifting capacity and in such a manner as to prevent damage to the galvanizing. The beams shall be braced in a plumb and square position until the concrete has cured. The age of the concrete before it is considered cured and before signs are permitted to be erected is to be in accordance with 630.

Breakaway Beams and Connections

1.        Ground-mounted sign supports of the breakaway beam type shall be rolled steel, wide flange sections of the size, and weight specified (from the list on SCD TC-41.10).

2.        Beam lengths appearing on the plans are approximate and the Contractor is responsible for determining the exact length of required beams before fabrication (630.06 A).

3.        Beams shall use a slip base design. Alternate designs of breakaway connections are permitted.

4.        Base plates shall be fabricated to standard details and welded-on with a bead equal to the beam flange and web thickness respectively, but not less than 1/4 inch (6.4 millimeters).

5.        Welding and Galvanizing shall be inspected in accordance with 630.

6.        All portions of beams should be shop assembled in accordance with SCD TC-41.10.

7.        The beam upper portions shall be joined by the bolts attaching the fuse and hinge plates. The plates shall be fabricated to standard details with the fuse plate having notched holes at the bottom and the hinge plate having unnotched holes. The steel hex head bolts, with washers under both head and nut, shall be tensioned in the shop to the final specified value.  For S4x7.7 (S100x11.5) beams only, malleable iron beveled washers are used under bolt head and nuts.

8.        Torque limiting nuts may be used instead of conventional nuts on the fuse and hinge plates (SCD TC-41.10, Note 5).

9.        The beam lower portions should be joined by steel hex head bolts inserted with their nuts uppermost. A galvanized bolt retainer plate shall be sandwiched between the base plates. Flat washers shall be used under both bolt head and nut as well as under the bolt retainer plate. Bolts shall be snug tightened for delivery to the site with final torqueing to be done after erection.

10.     Torque limiting nuts may be used instead of conventional nuts on the base plates (SCD TC-41.10, Note 5). The nuts shall be snug tightened, but not to the point where the upper area shears away.

11.     Base plate skewed notches should point toward the roadway along the path of typical vehicle collision. The skewed notches of both base plates should match.

Figure 630.C

12.     For beams located in medians, the base plates should be welded-on upside down as compared with those of beams located on the right side of the roadway, so the base plate skewed notches will point toward each roadway along the path of vehicle collision from either direction of traffic.

13.     For beams located in medians, fuse plates shall be used on both sides of the beam.

14.     For beams located on the right side of the roadway, fuse plates shall be on the side of the beam facing traffic.

Figure 630.D

15.     For the alternate design, special foot brackets shall be bolted to the upper beam portion, and four couplings incorporating a breakable reduced section are connected between the foot brackets and threaded anchor inserts embedded in the foundation. The couplings permit use of the design in medians where collision can occur in either direction of traffic.

16.     The alternate design uses four hinge/fuse plates incorporating a thinned section and bolted where the beam is cut through just under the sign. The pair of plates on the impact side of the beam and a pair on the opposite side bend severs upon impact to allow the beam to swing upward out of the path of the impacting vehicle.

17.     Beams should be erected in a single unit because they are easier to plum, square, and brace when the entire assembly is raised and set in concrete.

18.     Beams shall be erected in accordance with the procedure given for non-breakaway beams in 630.

19.     A sloping concrete foundation top surface is required on the high ground side to prevent a water pooling pocket and permit drainage as per SCD TC-41.10. For the alternate design, the foundation top shall be level in the area of the breakable couplings.

Figure 630.E

20.     When a supplemental panel is required below an extrusheet sign, the panel is fastened by sign backing assemblies to the parent sign. The panel shall be separated from the sign by the width of the fuse plate, plus 1 inch (25 millimeters). This is to permit unhindered hinge plate bending in the event of a vehicle collision.

21.     After the foundation concrete is cured, base plate nuts shall be loosened in turn and retightened with a torque wrench in a systematic manner to the specified maximum torque shown in the table on SCD TC-41.10, also shown in TEM Table 297-9. Torque wrenches used should be calibrated daily.

22.     When torque limiting nuts are used on base plates, the nuts shall be loosened in turn, and tightened in a systematic manner until the upper area shears away and ensures that the correct torque has been applied.

23.     At least 4 weeks following the erection of signs on breakaway beams, the breakaway feature shall be inspected by the Contractor for evidence of shifting or loose fasteners.

24.     All loose fasteners shall be re-torqued to specified values. Base plate fasteners shall be loosened and re-torqued even if no shifting or looseness is detected. If the base plate connection was made with torque limiting nuts, re-torqueing will only be required if looseness can be detected. Re-torqued conventional nuts shall have anaerobic adhesive applied, or as an alternate, new torque limiting nuts of the proper range may be used.

Rigid Overhead Supports (630.06.B)

Single Arm Support

1.        Single arm supports shall comply with certified shop drawings, SCD TC-16.20, and the plans.

2.        Welds, galvanizing, and general features of the support shall be inspected in accordance with 630.

3.        For arms of two telescoping pieces, a 15 inch (400 millimeters) overlap is required. The overlapped arms shall be secured with a stainless or galvanized steel hex head through bolt with nut.

4.        Arm caps shall cover at least 50 percent of the end area (Item 730.07).

5.        A minimum of two brackets shall be provided for each sign, each attached to the arm by steel clamps with carriage bolts. The clamps should be able to be tightened in a manner to firmly grasp the arm so as to prevent sign rotation.

6.        If signs are lighted, disconnect switch enclosure mounting brackets may be required on the support.

7.        Erection shall be in accordance with the general procedure given in 630, except as hereafter noted.

a.        The Contractor may choose to attach the signs and any sign lighting items before erection.

b.        Signs are installed at the same elevation. For this purpose, adjustment is provided by two pairs of slotted holes in the sign bracket for attachment of the arm clamp.

c.        Contact between galvanized clamp flanges and aluminum sign brackets shall be prevented by the use of chloroprene gaskets.

d.        Initial rake shall be adjusted so that under the load of signs, the pole will assume an essentially vertical position and the arm rise will be within the limits specified on the standard drawing, 3 inches (75 millimeters) minimum and 12 inches (300 millimeters) maximum.

 Cantilever Support

1.        Cantilever supports shall comply with certified shop drawings, SCD TC-12.30, and the plans.

2.        Welds, galvanizing, and general features of the support shall be inspected in accordance with 630.

3.        Supports with arm lengths 18 feet (5.5 meters) and over shall have truss members. Truss members may be angles or pipe.

Figure 630.F

4.        One blind half coupling shall be welded to the top chord approximately 12 inches (300 millimeters) beyond or outside of the first sign bracket for a sign less than 20 feet (6.1 meters) long. A second blind half coupling shall be welded near the second sign bracket for signs 20 feet (6.1 meters) or longer.

5.        Erection shall be in accordance with the general procedure given in 630, except as hereafter noted.

a.        The Contractor may choose to attach the signs and any sign lighting items before erection.

b.        Signs are centered vertically on the chords.

Center-Mount Support

1.        Center-mount supports shall comply with certified shop drawings, SCD TC-9.30, and the plans.

2.        Welds, galvanizing, and general features of the support shall be inspected in accordance with 630.

3.        Sign clearance above the roadway shall be a minimum of 17 feet (5.2 meters).

4.        Arms may be either square or round tube. The arm attachment design shall be in accordance with standard details for either square arms or round arms with separate cradle.

5.        A blind half coupling shall be located on the pole.

6.        Erection shall be in accordance with the general procedure given in 630, except as hereafter noted.

a.        Signs are centered vertically on the arms.

b.        Signs may be mounted laterally on the support in an eccentric position. However, a minimum of 2 feet (0.6 meter) of sign length shall remain to one side of the pole centerline.

c.        The Contractor may choose to attach the sign and any sign lighting items before erection.

 Semi-Overhead Support

1.        Semi-overhead supports shall comply with certified shop drawings, SCD TC-9.10, and the plans.

2.        Welds, galvanizing, and general features of the support shall be inspected in accordance with 630.

3.        Sign clearance above the ground shall be at least 10 feet (3.0 meters) unless a lower height is approved by the Project Engineer to provide sign visibility through preceding overpass structures.

4.        Arms may be either square or round tube. The arm attachment design shall be in accordance with standard details for either square arms or round arms with separate cradle.

5.        A blind half coupling shall be located on the pole.

6.        Erection shall be in accordance with the general procedure given in 630, except as hereafter noted.

a.        Signs are centered vertically on the arms.

b.        Signs may be mounted laterally on the support in an eccentric position. However, a minimum of 2 feet (0.6 meter) of sign length shall remain to one side of the pole centerline.

c.        The edge of the sign shall be back at least 2 feet (0.6 meter) from the edge of the curb.

d.        The Contractor may choose to attach the sign and any sign lighting items before erection.

 Span Truss Support

1.        End frames for span truss supports shall comply with certified shop drawings, the plans, and SCD TC-7.65 for aluminum trusses and SCD TC-15.115 for steel trusses.

2.        Welds, galvanizing, and general features of the support shall be inspected in accordance with 630.

3.        Handholes shall be oriented on the end frame downstream vertical member on the side away from the direction of traffic.

4.        The size of truss members shall be in accordance with standard details. Truss member joints may be of two different designs.

5.        Switch enclosure mounting brackets shall be in place and a chase nipple installed on both end frame vertical members, which are away from the direction of traffic.

6.        An angle shall be furnished and welded onto the end frame, near the top, to support the lower chords of the span box. Stainless steel U-bolts shall be used with aluminum trusses and galvanized steel U-bolts with steel trusses.

7.        End frame vertical members shall be furnished with steel clamps and a separate tee or angle (alternate) for supporting the upper chords of the span box. Stainless steel U-bolts shall be used with aluminum trusses and galvanized steel U-bolts with steel trusses.

8.        An internal J-hook shall be in each end frame in the downstream vertical member.

9.        When using an aluminum truss, the following shall apply:

a.        Aluminum trusses shall comply with certified shop drawings, SCD TC-7.65, and the plans.

b.        Welds shall be inspected according to 630.

c.        End caps shall be on each end of chords. The top front end caps shall be tapped for wiring.

d.        A blind half coupling shall be welded to the front top chord of the truss approximately 12 inches (300 millimeters) beyond or outside of the first sign bracket for each sign. Sharp edges shall be rounded to prevent damage to wires.

e.        Span length shall be in accordance with shop drawings and the plans.

f.         Span box camber shall be in accordance with standard details.

g.        Flanges between span box sections may be cast or fabricated with forged flanges as an alternate.

h.        Flange attachment hardware shall be stainless steel bolts and nuts.

i.         Supports shall be furnished with necessary sign brackets, U-bolts, luminaire support arms, bracing rods and other necessary structural members

10.     When using a steel truss, the following shall apply:

a.        Steel trusses shall comply with certified shop drawings, SCD TC-15.115, and the plans.

b.        Steel truss checking instructions are the same as those for aluminum trusses, except as hereafter listed.

                                                               i.      The galvanizing shall be inspected according to 630.

                                                              ii.      Flanges between span box sections shall be forged.

                                                            iii.      Flange attachment hardware shall be galvanized steel bolts and nuts.

11.     See the notes in the plan for traffic maintenance requirements when span type sign support members are erected.

12.     The base plates of end frames shall be placed on anchor bolt leveling nuts, plain washers and anchor nuts placed, the frames plumbed into a vertical position in both longitudinal and lateral directions, and nuts made tight in accordance with 630.

13.     Truss camber shall be correct. The various truss sections shall be assembled in the arrangement and sequence shown on the shop drawing.

14.     Trusses may be assembled into a total span while lying on blocks with wedges. Flanges on truss section ends may be aligned by driving in the wedges as necessary. All flange bolts are then assembled and made tight.

15.     Two cranes may be necessary when lifting very long trusses or the heavier steel trusses. For reference, truss weights are given in 630.

16.     Care should be taken in the attachment of slings. Trusses should be lifted at positions of a quarter to a third of the total span. Slings should be attached to the top chords and the horizontal diagonals.

Figure 630.G

17.     Trusses may be easily overstressed by poor handling, and care should be taken when moving assembled trusses for temporary storage, during transportation to the erection location, and in the erection procedure.

18.     Trusses shall not be erected unless at least one sign is in place within 8 hours or the trusses are fitted within the same period with damping devices approved by the Project Engineer (630.06 B).

19.     Attachment of the box truss to the end frames shall be by four U-bolts. Aluminum trusses shall be attached by 5/8-inch (16 millimeters) stainless steel bolts according to SCD TC-7.65 and steel trusses shall be attached by 3/4-inch (19 millimeters) galvanized steel bolts according to SCD TC-15.115.

20.     The Contractor may choose to attach the signs and any sign lighting items before erection.

21.     Signs are centered vertically on the chords (not considering the height of Exit Panels).

Span Wire Support (630.06.C)

Span Wire sign supports shall comply with SCD TC-17.10 and the plans. These sign supports consist of strain poles, messenger wire with accessories, and sign hangers. Strain pole size and type, anchor base, or embedded shall be as specified.

1.        Strain poles shall be inspected in accordance with 632 and general features of the poles shall be inspected in accordance with 630. Welds shall be inspected according to 630 and the galvanizing shall be inspected according to 630.

2.        Erection shall be in accordance with the general procedure given in 630, except as hereafter noted.

a.        For the initial rake of strain poles of the anchor base type or embedded type poles, see 632.

b.        The upper messenger wire shall be assembled with its accessories according to the standard drawing. Preformed guy grips are not permitted because wind loads on the signs can cause failure of the grips. Alternate methods of attaching messenger wire to strain poles may be used.

                                                               i.      Span wire clamp with clevis, anchor shackle and thimbles on the messenger wire, or

                                                              ii.      Messenger wire wrapped twice around the strain pole and secured with a 3 bolt clamp of the proper size.

c.        The upper messenger wire shall be fitted with its signs, furnished under other items of work, and the vertical clearance to sign bottoms adjusted within clearance limits over the roadway. The sag of the upper messenger wire shall be between 4 and 5 percent.

d.        It is essential that the lower messenger wire have more slack than the upper wire. The sag should be approximately 3 inches (75 millimeters) greater than the upper wire. This sag adjustment shall be made before the sign hangers are attached to the lower wire.

e.        Sign hangers shall be clamped snugly to the lower wire by U or J bolts. In the case of back-to-back signs, the lower messenger wire running in between the sign hangers is clamped between bolted spacers that are slightly thinner than the messenger wire (see SCD TC-17.10).

Overpass Structure Mounted Support (630.06.D)

1.        Overpass structure-mounted supports shall comply with the plans and SCD TC-18.24 for flush type supports and SCD TC-18.26 for skewed type supports.

2.        Overpass structure-mounted supports include sign brackets and two different kinds of steel Z-bars which are fastened to bridge concrete. For steel beam bridge mounting, aluminum angles at the bottom are to extend between sign brackets and short galvanized steel angles bolted to the bridge steel. For overpass structures essentially perpendicular to the roadway underneath, sign brackets are flush mounted to Z-bars for direct sign viewing. For overpass structures skewed to the roadway underneath, a wedge-shaped box structure is inserted between the sign brackets and Z-bars to provide for direct sign viewing.

3.        The number of sign brackets will vary according to the bracket spacing as required by SCD TC-22.20. Bracket details are also shown on the standard drawing.

4.        The number of aluminum frames in skewed supports shall equal the number of sign brackets. Frame details shall be in accordance with standard details and are to include two angles placed diagonally.

5.        Front upper and lower members of skewed supports shall be aluminum angles with a length equal to the sign length.

6.        The skewed support structure shall be internally braced by two aluminum angles extending diagonally and horizontally through the interior.

7.        For bridge clearance above a roadway of less than 17 feet (5.2 millimeters), the sign clearance above the bottom of the bridge shall be 3 inches (75 millimeters) minimum without or 15 inches (400 millimeters) minimum with sign lighting fixtures on the lower edge of the sign.

8.        Supports shall be mounted on the overpass structure so the sign is horizontal regardless of bridge slope (630.06 D).

9.        Expansion double wedge steel anchor bolts shall be used to fasten the support’s Z-bars to the overpass structure concrete parapet. Intended locations of anchor bolts are to be approved by the Project Engineer before any field drilling. Z-bars “A” are used at the top and Z-bars “B” at the bottom of parapet concrete.

Figure 630.H

10.     For a steel beam bridge mounting, aluminum angles at the bottom shall be fastened to short galvanized steel angles bolted to the bridge steel.

11.     Chloroprene gaskets shall be used to prevent contact between aluminum sign brackets or support frames and steel Z-bars or bolted-on angles.

12.     If the sign extends more than 4 feet (1.2 meters) above or below the attaching Z-bars, intermediate sign brackets shall be provided.

13.     For precast beam bridges, aluminum angles at the bottom shall be fastened to short steel angles and two expansion double wedge steel anchor bolts shall be used.

14.     After sign erection, the sturdiness of the support to bridge attachment should be checked.

Sign Erection (630.07)

General

This section provides information on erection of the signs. Assembly and erection of various types of overhead sign supports are addressed in 630.04 and 630.05 and ground-mounted supports are addressed in Section 630.06.

Ground-Mounted Flatsheet Signs

When erecting ground-mounted flatsheet signs, the following provisions apply:

1.        Typical vertical and lateral clearances of ground-mounted flatsheet signs are shown on SCD TC-42.20.

2.        Flatsheet signs shall be fastened to posts by 5/16-inch (8 millimeters) hex head steel bolts with a 3/8-inch (10 millimeters) ID x 1-1/4-inch (32 millimeters) OD wide washer under the bolt head and using a lock washer and hex nut. For U-channel posts, at each bolt, a bearing plate shall be used behind the sign to reinforce the sign, as indicated on SCD TC-41.20. The hardware and bearing plates are furnished with the signs.

3.        Posts supporting groupings of flatsheet signs in multiple arrangements will require the use of sign backing assemblies made up of bolted together short sections of posts. Sign backing assemblies are furnished with the signs unless separately itemized.

4.        Flatsheet signs mounted so as to be read by motorists using bridges shall be erected on special steel posts in accordance with SCD TC-41.40.

5.        Street Name signs shall be erected on square supports in accordance with SCD TC- 41.40.

Ground-Mounted Extrusheet Signs

When erecting ground-mounted extrusheet signs, the following provisions apply:

1.        Typical vertical and lateral clearances of ground-mounted extrusheet signs are shown on SCD TC-42.10.

2.        Mounting clips and other attachment hardware shall conform with SCD TC-51.11.

3.        Supplemental panels erected underground-mounted extrusheet signs mounted on non-breakaway beams shall be fastened directly to the beams. The panel shall be separated from the parent sign by 1 inch (25 millimeters) to conform with SCD TC-42.10. When the panel is too short to reach between the beams, the panel may be fastened to the parent sign by sign backing assemblies.

4.        Supplemental panels erected underground-mounted extrusheet signs mounted on breakaway beams shall be fastened to the parent sign by sign backing assemblies. The panel shall be separated from the parent sign by the width of the fuse plate plus 1 inch (25 millimeters).

5.        Exit Panels erected above extrusheet signs shall be attached by sign backing assemblies furnished with the Exit Panel.

6.        The signs should be checked after erection to verify that the beams extend to the top of the signs and that the signs are horizontal and the clearances satisfactory.

Overhead Signs

When erecting overhead signs the following provisions apply:

1.        The clearance above the roadway for the bottom of overhead signs shall be a minimum of 17 feet (5.2 meters) or as shown on the plans.

2.        Overhead signs shall be vertical or horizontal regardless of the sag of supporting messenger wire, mast arm rise, chord camber, or overpass slope.

3.        Signs erected on span wire supports shall be attached in accordance with SCD TC- 17.10.

4.        Signs erected on single arm supports (SCD TC-16.20) shall be installed so their bottom edge is at the same elevation. Sufficient adjustment for this purpose is provided by the two pair of slotted holes in the sign brackets for the attachment of the arm clamps. The clamps shall be tightened sufficiently to prevent sign rotation about the arm.

5.        Signs mounted on semi-overhead supports (SCD TC-9.10) shall be erected so that their edge clearance from the curb line is at least 2 feet (0.6 meter).

6.        Extrusheet signs over 8 feet (2.4 meters) in height may be delivered in two pieces for assembly in the field (630.08).

7.        Extrusheet signs erected on supports with two arms shall be centered vertically.

8.        Mounting clips and other attachment hardware for extrusheet signs shall conform to SCD TC-51.11.

9.        Signs mounted on center-mount supports (SCD TC-9.30) may be mounted laterally on the support in an eccentric position when required by the plans. However, a minimum of 2 feet (0.6 meter) of sign length shall remain to one side or the other of the vertical member centerline.

10.     Overlay signs erected in the field over existing extrusheet signs shall be attached by blind rivets at spacings as required in 630.04.

11.     Flatsheet signs used in connection with signals supported by span wire shall be fastened to the messenger wire by special attachments in accordance with SCD TC-41.41.

12.     Flatsheet signs used in connection with signals supported in a swinging condition on mast arm supports shall be fastened to the arm by a special attachment in accordance with SCD TC-41.41.

13.     Exit Panels erected above extrusheet signs shall be attached by sign backing assemblies furnished with the Exit Panel.

14.     Extrusheet signs shall be attached to rigid overhead supports using sign brackets in accordance with SCD TC-22.20.  Signs extending more than 4 feet (1.2 meters) above or below an attachment point require the use of intermediate sign brackets.

Sign Shipment and Storage (630.08)

Signs shall be suitably protected and identified for shipment and storage. Extrusheet signs shall be kept rigid by backbracing or crating and the sign face covered with protective material. The backbracing shall extend sufficiently below the sign lower edge to keep the sign off the ground.

Extrusheet and flatsheet signs shall be stored in a vertical position.

Signs must be stored in such a manner that the packaging paper or cardboard material does not get wet. If the packaging material or slip sheeting should become wet, the paper should be removed immediately from contact with sign faces to prevent damage to reflective sheeting on the faces.

In the case of signs furnished by ODOT for erection by the Contractor, the Contractor shall be responsible for the storage and care of the signs after their transfer (630.08).

Sign Inspection (630.13)

After sign erection, the Contractor shall inspect all signs under both day and night conditions. Any necessary adjustments in lateral position or orientation to correct visibility deficiencies shall be made to the satisfaction of the Project Engineer (630.13).

Overhead Guide Signs should typically be centered over the lane(s) to which they apply. Down arrows on the signs should normally be centered over the proper lane as viewed by the road user.

The maximum displacement of a down arrow from the center of a lane should not be more than 2 feet (0.6 meter).

Overhead Guide Signs situated on curved roadways and incorporating down arrows may have the arrow(s) adjusted within the sign and/or the entire sign moved laterally so the arrows, when seen from a typical viewing distance on the curve, will appear to be over the proper lane(s).

Night conditions inspection is to assure that each sign has visible and uniform reflectivity. Any signs not having proper reflectivity should be noted and cleaned or replaced by the Contractor.

Documentation Requirements – 630 Traffic Signs and Sign Supports

1.        Ensure signs and supports are in compliance with plans and approved catalog sheets.

2.        Document depth, diameter, or foundations.

3.        Document steel and clearance maintained (if used).

4.        Document support stubs (if placed).

5.        Document anchors: diameter and depth (if used).

6.        Document size and depth driven of drive post used.

7.        Document curing used on concrete.

8.        Measure appropriate units for foundations and/or supports used and turn in for pay.

9.        Document type, size, background sheeting, and legend sheeting for signs.

10.     Measure signs and turn in for pay as per 630.14.

631 Sign Lighting and Electrical Signs

General (631.02)

Sign lighting is not necessary for overhead guide signs when Type H or J reflective sheeting is used for the reflective legends.  Therefore, for new installations, sign lighting will normally not be used.

Guidelines and design information on sign lighting are addressed in TEM Sections 212 and 240-7.

This section provides additional information about what to look for when installing sign lighting.

1.        Check certified shop drawings, catalog cuts, etc. for luminaires, ballasts, switches, and enclosures.

Figure 631.A

2.        Luminaires for mercury vapor sign lighting shall comply with 731.01 and shall consist of a housing that contains a reflector, lamp socket, wiring, and a door containing a glass lens or refractor, which meet the following requirements:

a.        The housing shall be adequately reinforced cast aluminum with a natural finish or painted gray.

b.        The reflector shall be highly reflective aluminum.

c.        The lamp socket shall be a porcelain shrouded mogul screw with lamp grips and a large center spring, which provides firm contact with a lamp base.

d.        The door shall be an aluminum frame cast with either a natural finish or a formed extrusion with an anodized finish. The door shall be hinged securely to the housing and be provided with a spring loaded latch. Hinges shall be stainless steel and designed so that unintentional door separation is impossible. Latches shall be stainless steel and are not to require tools for opening.

e.        A flexible, readily removable gasket shall be attached to the housing or door so a waterproof seal is formed when the door is closed and the gasket compressed. The glass lens shall be mounted within the door and sealed with elastic cement or a gasket.

f.         The glass lens shall be borosilicate or equivalent and able to withstand hail or the thermal shock of freezing rain.

g.        Drainage weep holes shall be provided in the housing or the door depending upon the luminaire’s bottom or top position on a sign.

3.        Mercury vapor lamp sizes shall be as specified. Ballast type shall match the specified lamp wattage. Lamp watts and ANSI code are shown in TEM Table 297-11 and SCD TC-31.21.

4.        Sign lighting shall be controlled by a disconnect switch within an enclosure. The switch shall be a two-pole minimum, single throw, fused safety disconnect type rated at 600 volts and 30 amperes (C&MS Item 631.06). The fuse size shall be as specified. A solid neutral bar shall be provided.

5.        The enclosure shall be weatherproof and lockable, complying with NEMA standard Type 4 ICS 1-110.15. Enclosure size shall be as specified (See SCD TC-32.10).

6.        Each enclosure shall be furnished with at least one padlock. Padlocks shall have a corrosion resistant body and a corrosion proof steel shackle. All padlocks for a project are to be keyed alike from an appropriate master key number obtained by the Contractor from the maintaining agency.

7.        Sign service to the enclosure shall be in accordance with the plans. Service wiring cable size shall be as specified, single conductor rated at 600 volts and no less than Number 4 AWG (631.04). Sign service underground from a pull box to a foundation mounted support, or to a support mounted on a concrete median barrier, is shown on SCD TC-32.10. Sign service from a direct drop is shown on SCD TC-32.11.

8.        Sign wiring from the disconnect to the luminaires shall be the size specified, single conductor rated at 600 volts and no less than Number 10 AWG (631.05). The wiring shall be fully protected within enclosures, support interiors, junction boxes, rigid or flexible conduit, and luminaire housings. Wiring shall be continuous from the disconnect switch to a junction box mounted on the sign support or overpass structure. The junction box shall permit disconnection of wiring when a sign and its lighting equipment are removed as a unit. A junction box shall be installed for each sign. Wiring shall be continuous from the junction box to the first luminaire on a sign and continuous between additional luminaires on the sign.

9.        Luminaire ballast shall be located within the luminaire (integral) or in a weatherproof housing attached to or beside the luminaire (contiguous). Wiring to the ballast shall be continuous with permitted disconnection at the sign support junction box (see paragraph 8).

10.     The wiring routing for wired signs shall be as shown on SCD TC-31.21.

11.     Luminaire supports complying with SCD TC-31.21 are specified for new installations. Support arms are of welded tubular design incorporating an attachment flange and a luminaire support plate. The arms are bolted to a continuous rectangular galvanized steel tube forming the lower portion of the sign’s glare shield. The face of the rectangular tube shall be covered with non-reflective sheeting, which complies with 730.20, so as to match the color of the glare shield sheeting. Support arms shall not be mounted upside down or in any other manner than that permitted by the SCD.

12.     Luminaires shall be adjusted to a proper aiming angle according to the manufacturer’s instructions and inspected at night to determine if they are providing uniform illumination to the sign face.

Inspection and Testing (631.11)

1.        In accordance with 631.11, sign lighting and electrical signs shall meet the requirements of the following tests as required by 625.19 and performed by the Contractor:

a.        Ground rod resistance to ground (see 632).

b.        Cable insulation (Megger) test (see 632).

c.        Ten-day performance test (see 632).

2.        During the 10-day performance test, failure of lamps, ballasts, and transformers may be corrected by replacement of the faulty component, but will not require restart of the entire test period.

3.        The Contractor should perform a circuit test on all sign lighting cable and wire conductors to determine if there are any short circuits, cross circuits, or other improper connections. Circuit testing may be done in accordance with 632.

4.        The test results shall be reported to the Project Engineer in the test information required by 625.19. The test results should be documented.

5.        During the 10 day performance test, a night inspection shall be performed by the Contractor and final adjustments made to sign lateral positions and the aiming angle of luminaires to the satisfaction of the Project Engineer (631.11). The adjustments are to eliminate excessive brightness and glare and to obtain optimum sign face reflected brightness, uniformity of illumination, visibility, and legibility.

6.        Following successful completion of a 10-day performance test and after there has been a partial or final acceptance of the project, the Contractor should turn over to the Project Engineer all manuals, diagrams, instructions, guarantees, and related material. The Project Engineer should transfer the material to the maintaining agency. For ODOT maintained signs, the material should be given to the appropriate ODOT District Office.

7.        After the project has been accepted by ODOT, the Project Engineer should immediately notify the maintaining agency that as of a certain exact time and date, the agency is responsible for the maintenance.

Documentation Requirements – 631 Sign Lighting and Electrical Signs

1.        Ensure signs and supports are in compliance with plans and approved catalog sheets.

2.        Document depth, diameter, or foundations.

3.        Document steel and clearance maintained (if used).

4.        Document support stubs (if placed).

5.        Document anchors: diameter and depth (if used).

6.        Document size and depth driven of drive post used.

7.        Document curing used on concrete.

8.        Measure appropriate units for foundations and/or supports used and turn in for pay.

9.        Document type, size, background sheeting, and legend sheeting for signs.

10.     Measure signs and turn in for pay as per 630.14.

632 Traffic Signals and 633 Signal Controllers

General

This information is intended to serve as a guide for construction personnel where the Contractor furnishes and installs traffic control devices and appurtenances. It may also be useful for maintenance personnel performing the same functions. Inspection procedures for the various type traffic control devices are outlined, mainly in the form of checklists, to assist project personnel in performing their duties. This information points out the various important features of each device and references the applicable specification or standard drawing. Illustrations are used for easy recognition of the device or feature being discussed.

Qualified Products List (QPL)

All 632 and 633 devices should be checked against the Qualified Products List before they are incorporated into a project.

Foundations (632.14)

See Item 630 for additional information relative to concerns regarding the installation of foundations for poles and controller cabinets.

Electrical Appurtenances

General

This section will be used to provide additional information about various electrical appurtenances involved in the traffic signal installations, such as pull boxes, conduit, and ground rods.

Pull Boxes

Pull boxes shall be of the specified sizes (see SCD HL-30.11 and the plans), typically 18 inches (460 millimeters) or 24 inches (610 millimeters), and the specified material.

The word on the cover should be, Traffic, when the pull box is part of a traffic signal system unless the plans require the word, Electric, or other marking. The word shall be formed on the surface or displayed on an attached metal plate.

The location of pull boxes shall be as shown on the plans. However, pull boxes in low drainage areas may be adjusted to eliminate drainage problems, or feasible methods of positive drainage may be used in accordance with 611 and details on SCD HL-30.11 with the approval of the Engineer.

Pull boxes located in sidewalks, traffic islands, and curbed areas close to the roadway, where wide turning vehicles could drive over them, may be adjusted to eliminate the problem, or a concrete pull box with a heavy duty lid may be used with the approval of the Engineer.

Trench

Trenching shall be in accordance with 625. Any change in dimensions will require approval by the Engineer.

Trenching may be in earth or in paved areas according to plan details. Trenching and subsequent restoration of surfaces in paved areas shall be in accordance with SCD HL-30.22.

Trenching work in paved areas shall be divided into two pavement depths for payment: less than 6 inches (150 millimeters) and 6 inches (150 millimeters) or greater (625.20).

The trench in paved areas may be 4 inches (100 millimeters) wide when cut by a Vermeer type trencher. In this case, the trench shall be backfilled with concrete full-depth, except the bottom 4 inches (100 millimeters) above the conduit may be 625.13 tamped backfill.

Conduit

Metal conduit shall comply with 725, with sizes according to the plans. It shall be made from domestically produced steel, and the domestic steel content of the conduit shall be certified by the manufacturer or supplier before it is approved for installation.

The routing of loop detector wire in conduit through curb or under shoulder shall be as shown on SCD TC-82.10.

Conduit containing cable and/or wire shall have the terminal at the high end completely sealed in an approved manner, with removable sealing compound or a molded plastic or rubber device compatible with the conduit, cable jacket, and wire insulation according to 625.

After placement, a conduit which will not have cable or wire pulled into it during construction shall have a pull wire installed in it. The terminal at the high end shall be sealed with removable sealing compound, a molded plastic, or a rubber device according to 625.

Difficult pulling and possible jacket skinning may occur when an attempt is made to install too many cables or wires within a given conduit. The reason could be design error in new systems or attempts to insert an excess number or size of cable or wire in existing conduit.

Good electrical practice requires that the combined cross-section of all cables and wire within a conduit should be less than or equal to 40 percent of the conduit inside area:

a1 + a2 + a3 + etc. < 0.40Ci

a = Cable or wire across section area, sq. in. (mm²)

Ci = Conduit inside area, sq. in. (mm²)

A calculation can be made using the above formula. The cross-section area of conduit, cable, and wire is shown in TEM Table 497-1.

Ground Rod

A ground rod shall be driven below groundline near the foundation of every strain pole and overhead sign or signal support whether there is power in the vicinity or not, as shown on SCDs TC-21.20, TC-32.10, and TC-32.11.

Ground rods shall comply with 725 and be installed in accordance with 625.  A ground wire of insulated 600 volt No. 4 AWG 7-strand soft drawn copper shall be attached by an exothermic weld. The typical exothermic weld procedure is described in 632.

Insulating varnish shall be applied to the weld and any exposed conductor.

Exothermic Weld

The following procedure is typical and may be used unless the manufacturer’s instructions differ.

1.        The end of the ground wire shall be in an un-flattened, unbent, clean, and dry condition to ensure a good weld.

a.        Bent and out-of-round conductor wire will hold the mold open causing weld material leakage. A cable cutter should be used to make un-deformed ends. If a hacksaw is used, the insulation should first be peeled, as the saw tends to coat the cable with plastic material, which must be cleaned off.

b.        Corroded cable shall be cleaned. Oily or greasy cable should be cleaned with a solvent that dries rapidly and leaves no residue. Very greasy cable can be cooked out by dipping into molten solder.

c.        Wet cable can cause molten metal to blow out of the mold, and the cable should be dried by a hand torch or a quick drying solvent such as alcohol.

2.        Ground rod ends which have been mutilated in driving can hold the mold open and should be cut off. Rod ends shall be clean and dry.

3.        The weld mold shall be clean before use. Damp or wet molds can cause porous welds and should be dried by heating.

4.        The cable shall be inserted into the side of the mold so the cable is 1/8 inch (3 millimeters) back from the center of the tap hole. The mold shall be placed on the ground rod so the cable sits on top of the rod. A clamp or locking pliers should be used on the rod to keep the mold from sliding down during the welding process. The conductor should be marked at the mold surface so it can be verified that the conductor has not shifted before the weld is made.

5.        The steel disk shall be inserted into the crucible and the cartridge contents poured on top, being careful that the disk is not upset. The cartridge should be tapped when pouring to make sure the starting powder comes out and spreads evenly over the welding powder. A small amount of starting powder should be placed on the top edge of the mold under the cover opening for easy ignition.

a.        The proper cartridge size is marked on the mold tag and is the approximate weight of the powder in grams.

b.        If the proper cartridge size is not available, two or more small cartridges or part of a larger cartridge can be used.

6.        The mold cover will be closed and the starting powder ignited with a flint gun. If it is necessary to hold down the cover during the flash of igniting powder, a long tool should be used and the hand should be kept away.

Pole and Support Inspection - General

See 630 for information about pole and support inspection.

Signal Support (632.15) and Strain Pole (632.16)

General

This section will be used to provide additional information about traffic signal supports. Various types of overhead signal supports are also depicted in TEM Table 497-4.

Strain Pole Type Support (632.16)

Strain poles shall comply with the certified drawings and the plans.

They shall be galvanized unless paint is specified in the plans, and the general features should be inspected in accordance with 630.

Strain poles used to support traffic signals or signs (SCD TC-17.10) shall be furnished with one or more span wire clamps with shackles for attachment of messenger wire (see SCD TC-84.20).

Only messenger wire may be attached by wrapping twice around the pole and securing with a three-bolt clamp, as shown in SCD TC-84.20, when used on round, tapered steel strain poles.  Tether wire shall not use the alternate wrap method.

Erection of these poles shall be in accordance with the general procedure given in Section 630, except as noted in this section.

For the initial rake of strain poles of the anchor base type, leveling nuts shall be adjusted to provide a rake of 1/8 to 1/2 inch per foot (11 to 42 millimeters per meter) of pole in the direction opposite to the contemplated span wires and are to be made snug tight. Further adjustment may be necessary to ensure that the strain poles are vertical after the application of span wire load.

Single Arm Support

Single arm supports shall comply with the certified drawings, SCD TC-81.21, and the plans. General features of the support shall be inspected in accordance with 630, and except as noted in this section, erection of the support shall be in accordance with the general procedure given in 630.

Welds shall be inspected according to 630 and the galvanizing inspected according to 630.

For arms of two telescoping pieces, a 15-inch (380 millimeters) overlap is required. The overlapped arms shall be secured with a stainless or galvanized steel through-bolt with hex head washer and nut(s).

An arm clamp with clevis shall be furnished at each signal position as well as a hole with a rubber grommet for the outlet of signal cable.

The installation of small signs and their attachment to the arms should be checked. Any possible interference between swinging signals and signs should also be checked.

Blind half couplings shall be located on the pole of the support for mounting pedestrian signal heads or controller cabinets when required by the plans.

Signal heads shall be installed so that their bottom surface is 16 to 18 feet (4.9 to 5.5 meters) above the roadway. The signals shall be installed at essentially the same elevation. Drop pipes should be used only when necessary to maintain the clearance between 16 to 18 feet (4.9 to 5.5 meters). If the clearance without a drop pipe is slightly over 18 feet (5.5 meters), it is permissible to omit the drop pipe, with the maintaining agency’s approval.

Initial rake shall be adjusted so that under the load of signals, the pole will assume an essentially vertical position and the arm rise will be within the limits specified on SCD TC-81.21 (i.e., 3 inches [76 millimeters] minimum and 12 inches [300 millimeters] maximum).

Sag and Vertical Clearance

TEM Figure 498-13 illustrates sag guidelines and vertical clearance standards for traffic signals.

Cable Support Assemblies (632.21)

A cable support assembly makes use of a flexible, tubular, wire mesh device called a cable grip, which has a gentle holding action over its length and is used to eliminate strain or damage to the jacket of cable(s) hanging in the interior of poles.

The support assembly consists of the grip attached to a single “U” eye support bale and a sling when necessary. The grip may be used on an individual cable or a group of cables up to a maximum of four. The grip shall be the proper size and strength for the cable(s), of stainless steel or tin coated bronze, and may be either a “closed” or “split with rod” type. The split type is used when a cable end is not available. In this application, the grip mesh is not a continuous tubular weave, but is split for wrapping around the cable(s) and is secured by a rod which is inserted through alternate weaves at each side to form a tube.

The support’s bale shall be hung over the pole J-hook if sufficient length is available; otherwise, a sling shall be made of messenger wire, clamps, and thimbles. The sling wire is to be passed through the bale eye, adjusted to the proper length, and hung on the J-hook.

Pole interiors should be checked by removing pole caps to verify that cable support assemblies are in place, hung on the J-hook, and properly adjusted to eliminate cable jacket strain.

Aerial Interconnect Cable

For aerial interconnect cable, the following standards and guidelines apply:

1.        Aerial interconnect cable and accessories shall comply with SCD TC-84.20. Interconnect cable may be supported on separate messenger wire or be the integral messenger, self-supporting type, with a, "figure 8,” cross-section, if specified on the plans.

2.        Metal poles with messenger wire supported interconnect cable are to be furnished with pole clamps. The pole clamp may provide clevis(es) to which the messenger is attached and terminated or may provide a stud to which a clamp assembly can be bolted.

3.        Messenger wire ends are to be looped and secured with three-bolt clamps or a messenger vise, or a preformed guy grip dead end may be used (see 632). If clamps or vises are used, the wire tail shall be served (see 632). Thimbles with a correct groove size for the messenger wire shall be used to connect to the clevis of the pole clamp.

4.        When messenger wire is to be grounded to a metal pole, a ground clamp, an insulated ground wire, and a bolt tapped into the pole shall be used (also see item 10 in this section).

5.        Wood poles with interconnect cable shall be fitted with through-bolts holding a clamp assembly or with a thimble eye-bolt to which the messenger may be attached and terminated.

6.        The clamp assembly shall be suitable to the type of cable support, either messenger wire or self-supported cable with "figure 8" cross-section. Clamp assemblies for "figure 8" interconnect cable differ slightly from those intended for use with separate messenger, since the clamp used with "figure 8" must allow a small gap for the web of the "figure 8" cable which joins the messenger to the cable.

7.        When messenger wire or "figure 8" cable is to be grounded on a wood pole, a ground clamp and an insulated ground wire, stapled to the pole and covered by a molding, shall be used (see Item 10 in this section). The ground clamp used with "figure 8" cable shall be a type with teeth to penetrate the jacket over the messenger. The ground wire shall be bonded to an existing ground wire or to a ground rod.

8.        Standard interconnect cable shall conform to C&MS Table 732.19-1 and have the number of conductors and wire gauge specified. There is no difference between standard interconnect cable and signal cable, only in the application. Interconnect cable of the shielded type may be specified in the plans. The interconnect cable should be marked with the correct nomenclature. Solid conductors are not permitted (732), unless specified in the plans. Splices may be used on long lengths of interconnect cable (632) and shall be accomplished only in weather tight splice enclosures. Splice enclosures may be either aerially located on the messenger wire or be a pole-mounted box type (see SCD TC-84.20). Where the aerial enclosure is clamped to the span, it should be within 2 feet (0.6 meter) of a pole to improve accessibility. No measurement allowance is given for splices.

9.        Aerial interconnect cable is to have a sag between three to five percent of pole spans or is to match existing utility lines.

10.     Messenger wire supporting interconnect cable, and the integral messenger of self-supporting type cable, is to be grounded in cable runs at the first and last poles and on intermediate poles at intervals not to exceed 1,200 feet (366 meters). See Item 4 of this section for grounding on metal poles and Item 7 for grounding on wood poles.

11.     As temperatures decrease, interconnect cable gets stiffer and harder, becoming brittle when below freezing. In very cold weather, the cable should be handled with care so as not to damage the jacket or insulation when unreeling, flexing, and installing.

12.     Standard interconnect cable may be attached to supporting messenger wire by lengths of preformed lashing rod or by spinning wire. Lashing rods shall be of the proper internal diameter to snugly hold the cable, but not cut into its jacket (see 632).

13.     Aerial interconnect cable of the integral messenger, self-supporting type (with a "figure 8” cross-section) shall have its wind stability increased by being twisted or spiraled once every15 feet (4.6 meters) of span. This is done by clamping the tensioned cable to every other pole and then going to intermediate poles and twisting the cable before tightening their attachment clamps.

14.     When the interconnect cable is attached to a pole and continues in a relatively straight line past the pole, this is an intermediate support; however, if the interconnect cable turns at the pole, it is a corner or turning point. Certain types of clamps may be well suited for intermediate support applications, while other designs are required for corner clamps. The clamps shown on the left side in SCD TC-84.20 are usually not suitable for corner clamps if the change of direction is more than 10 degrees. See SCD TC-84.21 when the change of direction is more than about 10 degrees.

Tether Wire and Appurtenances

Tether wire and accessories shall comply with SCD TC-85.20, Plan Insert Sheet (PIS) 208521 and C&MS 732.185. S-hook wire diameter shall be in accordance with the strain pole Design Number, as shown in the plans.

The tether span, as shown in the standard drawings, is designed to yield under either high wind loads or vehicle snags. The S-hooks are designed to yield in a wind event, allowing the signal span to revert to a free-swinging configuration. The breakaway tether anchors are designed to release the tether in the event of a vehicle snag.

The use of a backplate and tethered span increase the frontal area of a 3-section signal head by a factor of approximately nine times that of a free-swinging signal head without backplates. Such an increase in a design wind will exceed AASHTO allowable stress levels in the strain pole. For this reason, it is important to provide a yielding element on the tether span that unloads the tether at the proper tether wire tension. For purposes of design, ODOT has chosen S-hook sizes based on the strain pole Design Number. The table in PIS 208521 gives the diameter of the S-hook corresponding to various pole Design Numbers. The S-hook must be galvanized, mild, low-carbon steel. High-strength alloy steels, such as Grade 80, sometimes used for load-rated S-hooks in the rigging industry, are not acceptable. These are much too strong for the application and will overload the strain pole in a design wind.

The use of breakaway tether anchors to attach signal heads to tether wire is required. Designs which use an L-shaped clamp, as shown in SCD TC-85.20, are acceptable. These shall be properly installed, with the cable clamped below the pinch bolt and the opening facing downward. This allows the tether wire to slip out in the event of a vehicle snag.

The turnbuckle used at the end of the tether span is a tensioning and leveling device used to bring the tether into its proper configuration after erection. On all spans, the tether wire must remain essentially horizontal.

The guy grip end also serves as the anchor point for the safety tie. The safety tie is an accessory feature designed to prevent the loose end of a tether span from dropping into the roadway in the event of an S-hook yield. As such, the safety tie need not be particularly strong. In the event of a strong vehicle snag, the 1/8-inch safety tie is designed to yield at a lower load than the 1/4-inch tether wire. If a full-strength safety tie matching the tether wire diameter were used, the possibility would exist of a snagged tether wire overloading the pole. Since the safety tie is small-diameter wire rope, it is specified to be stainless steel, with stainless steel hardware, to minimize corrosion.

Messenger Wire (632.22)

General

This section will be used to provide additional information about signal span messenger wire and appurtenances.

Note that tether wire is distinct from messenger wire.  Messenger wire supports a significant vertical load.  Tether wire does not and is used to prevent:

Signal Messenger Wire and Cable

Messenger wire and accessories shall comply with SCD TC-84.20. Messenger wire diameter shall be in accordance with the plans.

The height at which the messenger wire is to be attached to the pole will, in some instances, be shown on the plans. In cases where this is not shown, the Contractor is responsible for determining the proper attachment height. This determination shall consider the relative elevation of pavement to pole foundation top, the desired clearance between pavement and the bottom of each signal (i.e., 16 to 18 feet [4.9 to 5.5 meters]), the sag in the messenger wire (3 to 5 percent), and the height of each signal.

Alternate methods of attaching messenger wire to strain poles may be used as follows:

1.        Span wire clamp with clevis, anchor shackle, and thimbles on the messenger wire.

2.        Messenger wire wrapped twice around the strain pole and secured with a three-bolt clamp of the proper size when used on round, tapered strain poles.

If the messenger wire attachment to strain poles makes use of the alternative with pole clamps and anchor shackles, the wire is to be hooked through the shackle using a thimble and secured with a three-bolt clamp. A preformed guy grip shall not be used for messenger wire attachment at the pole. Guy grips of the proper size may be used at bull rings (aerial corners).

Thimbles with a correct groove size for the messenger wire (or the wire and eye of guy grips) are to be used at anchor shackles and bull rings. When three-bolt clamps are used, the wire tail is to be served as shown in the section on messenger wire. See the section, Messenger Wire, for the installation procedure for preformed guy grips.

Thimbles with a correct groove size for the messenger wire or the preformed guy grip shall be used to connect to anchor type shackles or bull rings at span wire aerial corners.

Messenger wire sag shall comply with 632 and the section, Sag and Vertical Clearance.

The signal cable shall be attached to the messenger wire by lengths of preformed lashing rod.

The lashing rod shall be the proper internal diameter to snugly hold the cable, but not cut into its jacket. See the section, Wire Lashing, for further information.

A drip loop shall be formed in the signal cable at each weatherhead and should extend at least 6 inches (150 millimeters) below the weatherhead.

Cables or groups of cables (up to a maximum of four), hanging within pole interiors, shall have their strain relieved by cable support assemblies as described in 632 and SCD TC-84.20.

Messenger Wire Served Ends

Messenger wire may be attached to various accessories by looping the wire to make an eye.

The wire end shall be secured by a three-bolt clamp, and the cut wire end or tail shall be served with construction wire or clamped with a sleeve device, as shown on SCD TC-84.20. The following illustrations show both serving methods for the wire tail:                          

Figure 632.A

Figure 632.B

Preformed Guy Grips

Preformed guy grips are made of helically shaped, high-strength steel wire. They are available in sizes fitting the outside diameters of messenger wire and form an eye permitting attachment to various accessories.

As shown in SCD TC-84.20, they should be used at bull rings of span wire aerial corners (see the following illustration). Thimbles are used in the eye of grips in accordance with standard details in the SCD.

Figure 632.C

Grips are installed on an end of the messenger wire by wrapping a first leg of the grip to the messenger wire. In most cases, the accessory to which the grip is to be attached must be inserted in the eye of the grip with a thimble before the second leg of the grip is wrapped. The second leg is then applied to the combined first leg and messenger wire. The following illustrations show the wrapping sequence.

Guy grips shall not be used on messenger wire used for span wire sign supports. In this application, wind load on the signs can cause failure of the grips (see SCD TC-17.10). Guy grips shall not be used for attachment to signal strain poles (SCD TC-84.20(5)).

Figure 632.D  

Figure 632.E

Cable and Wire (632.23)

In certain instances, the plans will assign a color code usage for each cable or a typical usage by color code. All connections should be made observing these assignments, and any deviations, if determined necessary, should be recorded. When a color code usage is not provided, good electrical wiring practice would still dictate that color code wiring on the project be consistent.

Typically, white is reserved for the neutral or common leg of a circuit. The following provides additional information about various types of cable and wire contained in Table 732.19-1:

1.        Signal cable is used as the electrical connection between signal heads and the controller cabinet at an intersection. The cable may be either IMSA 19-1, which has a jacket of polyvinyl chloride, IMSA 20-1, which has a polyethylene jacket, or IPCEA S-61-402. The number of conductors and wire gauge shall be as specified on the plans. Conductors shall be of copper and stranded, and conductor insulation shall be color coded. Splices are not permitted in signal cable and the cable should be scanned to be sure that there are none.

a.        As temperatures decrease, signal cable gets stiffer and harder, becoming brittle when below freezing. In very cold weather, the cable should be handled with care so as not to damage the jacket or insulation when unreeling, flexing, and installing.

2.        Interconnect cable is used as the connection between intersections for systems of signals.

a.        The cable may be either IMSA 19-1, IMSA 20-1, or IPCEA S-61-402 as in signal cable, or twisted pair/shielded interconnect cable, conforming to RUS PE-39, may be required by the plans.

b.        Twisted pair/shielded cables are less prone to pick-up induced current as a result of nearby electrical devices or magnetic fields. Twisted pair/shielded cables are necessary for certain types of communication systems which may be used to interconnect signals. The number of conductors and wire gauge shall be as specified. It should be noted that in the case of twisted pair/shielded cable, the number of conductors is typically referred to as the number of pairs or pair count (i.e., six conductor cable would be referred to as a three-pair cable). Conductors shall be of copper and are usually solid.

3.        Interconnect cable of the integral messenger type is aerial self-supporting cable with a, "figure 8," cross-section. The cable may be either IMSA 19-3, which has a jacket of polyvinyl chloride, or IMSA 20-3, which has a polyethylene jacket. Shielded versions, IMSA 19-4 and IMSA 20-4, may be required by the plans. The number of conductors and wire gauge shall be as specified. Conductors shall be of copper and stranded, and conductor insulation shall be color coded.

4.        Loop detector wire is laid in turns in saw slots cut into the pavement and routed by the groove to the edge of pavement and to a pull box. The wire is single-conductor No. 14 AWG.

a.        The conductor shall be of copper and stranded. Loop detector wire consists of detector wire inserted into a flexible plastic tubing (732) that meets specifications, IMSA 51-5. The tubing shall encase the wire completely from the splice at the lead-in cable through the entire loop turns and back to the splice.

5.        Lead-in cable for detector loops is spliced to loop wire and routed to detector units in the controller cabinet. The cable shall be two-conductor No. 14AWG with a jacket of 0.04 inch (1 millimeter) minimum black polyethylene and insulation of polyethylene. Each conductor shall be stranded copper. The conductor pair shall be twisted and shielded.

6.        Power cable is used as the connection between the service pole or service drop and the controller cabinet. The cable normally is two-conductor and UL:RHH/RHW/USE type. The wire gauge shall be as specified. Conductors shall be color coded, made of aluminum, and stranded.

a.        Stranded copper may be substituted with an AWG one gauge higher (wire one size smaller).

b.        When specified, power cable may be three-conductor. Single conductor cables may be substituted for a two (or three) conductor cable, but color coding should still be provided.

7.        Service cable is used to bring power to the vicinity of an isolated intersection. The cable is normally two-conductor (duplex) and XHHW type or cross-linked polyethylene with a 0.045 inch (1.14 millimeter) minimum jacket. The wire gauge shall be as specified. The cable is aerial self-supporting with one conductor being an uninsulated ACSR (aluminum conductor, steel reinforced) messenger wire. An insulated conductor of stranded aluminum is twisted around the messenger. Stranded copper with an AWG one gauge higher (wire one size smaller) may be substituted for the aluminum conductor. Three-conductor (triplex) may be specified where two insulated conductors are twisted around the messenger wire. The uninsulated messenger serves as the grounded neutral of the power supply.

8.        Ground wire is used to connect signal or sign supports to ground rods. The wire shall be single-conductor No. 4 AWG made of seven-strand soft drawn copper with white insulation and rated at 600 volts. The wire is used as part of the 625.16 Ground Rod item.

Lashing of Overhead Cable

A preformed helical lashing rod shall be of the proper internal diameter to tightly secure overhead cable(s) to the messenger wire. A lashing rod should not be loose or so tight as to be impressed deeply or cut into the cable jacket. If either deficiency is observed, the proper internal diameter may be determined by the following formula: C approx. = (0.85) (D+m), where C is the lashing rod internal diameter, D is the cable jacket diameter, and m is the messenger wire gauge (all dimensions in inches [millimeters]).

For groups of several cables of varying diameter, the internal diameter of the lashing rod may be best determined by a graphic layout to scale.

Signal cable routed on messenger wire should neatly pass the bull rings in its path. Also, signal cable routed around an aerial corner formed in the span wire at a bull ring should have a radius in its routing small enough to form a tangency with the bull ring.

Figure 632.F

Figure 632.G

Power Service (632.24)

General

Power service for traffic signals shall comply with SCD TC-83.10 and the plans. It shall consist of the equipment needed to provide a pole-attached wiring raceway and disconnect switch for use with separately furnished power cable routed from the service point to the controller cabinet. Unless otherwise specified, the equipment includes a weatherhead, a conduit riser with necessary fittings, and attachment clamps as well as a disconnect switch with enclosure.

A thorough review of the plans should be made to determine that the specific requirements of the maintaining agency for power service have been satisfied.

A ground wire shall be used, as shown on SCD TC-83.10, leading to a ground rod installed in accordance with 632.

The LB type fitting under the controller cabinet may have to be installed before erecting the pole because of interference with the foundation.

Electric Meter Base

When required, an electric meter base shall be furnished by the applicable utility and installed by the Contractor as part of the power service work.

Conduit Riser and Weatherhead

Power cable is the only type cable or wire permitted through the power service conduit riser.

If used, the conduit riser shall terminate at the meter base; otherwise, termination shall be at the switch enclosure. From there, the conduit connection to the controller cabinet is as shown on the plans. Conduit connection could be:

1.        Immediately to the controller cabinet on the same pole.

2.        Downward by underground conduit and possibly a pull box to a nearby foundation-based controller cabinet.

3.        Upward by another riser on the pole to span wire and a remote cabinet location.

The conduit riser shall comply with 725 and the plans. The weatherhead shall be threaded aluminum or galvanized ferrous metal. Risers on painted poles shall be painted to match the poles.

Disconnect Switch

The disconnect switch shall be a UL listed, single-throw safety switch or circuit breaker which meets the voltage and capacity requirements of the specifications. The amperage rating of the fuse or circuit breaker shall be 5 to 10 amperes greater than the peak load rating of the equipment service. The enclosure shall be a UL listed, water tight, lockable, stainless steel NEMA Type 4, supplied with UL listed conduit hubs, and the enclosure shall contain a solid neutral bar normally grounded to the enclosure.

Signal Equipment and Wiring

General

This section will be used to provide additional information about other signal equipment and wiring.

Controller Cabinet (632.05)

While the layout of controller cabinets may vary, the following requirements and guidelines apply:

1.        The prewired cabinet should be checked against certified drawings, the wiring diagram for the cabinet, and the plans.

2.        The cabinet should be fitted with a small door-in-door (police door), unless otherwise specified. The cabinet should be in good condition, revealing no evidence of damage, with its material free of cracks and pinholes. The doors and seals should fit properly. The cabinet exterior should appear as metallic aluminum, unless a color is specified. The cabinet interior may be similar to the exterior or may be flat white. The method of cabinet mounting should be as shown on the plans and the cabinet should be securely mounted.

3.        Cabinets equipped with solid state controllers shall be provided with a suitable number of sturdy adjustable metal shelves to mount the specified equipment and to provide the required space for designated future equipment.

4.        The equipment shall be arranged for easy withdrawal and replacement, without the necessity of disturbing adjacent equipment. The permanent location of equipment within the cabinet, as well as the shelves themselves, should allow free circulation of air and not restrict air flow from fan ducts or vents. Components on shelves and devices on the door shall be arranged so that a 1-inch (25 millimeter) minimum space separates them when the door is closed. This minimum space shall not be compromised by plugs, wires, controls, or similar items. Terminals and panel-mounted devices with exposed contact points located next to shelf mounted equipment shall be provided with spacers, shelf lips, or other means to assure that component units cannot be accidentally moved into contact with any exposed electrical terminal points. A minimum 4-inches (100 millimeters) clear area from the bottom of the cabinet should be reserved for the routing of cables. No shelf, component, or panel-mounted item shall be located in the bottom 6 inches (150 millimeters) of cabinets, with the exception that terminal blocks only in pedestal or pole mounted cabinets may be installed as close as 4 inches (100 millimeters) to the bottom.

5.        Ready accessibility should be provided for items such as load switches, flasher, relays, terminal blocks, and fuses which are mounted on or plugged into panels on the cabinet back or sides. Switches, controls, and indicator lights should be easily operable and visible without having to move equipment from their positions.

6.        Major equipment items should bear a name plate, brand, or indelible marking for identification as to type, model, catalog number, and manufacturer’s name or trademark.

7.        The furnished controller unit should be checked for the correct type, number of phases, and available control functions required by the plans. Controller units should be furnished with all auxiliary equipment necessary to obtain the operation shown in the plans.

8.        When specified, other equipment may be a part of the prewired cabinet, such as a coordinator, an on-street master, interconnection equipment, preemption equipment, time clock or weekly programmer, and special relays.

9.        Furnished detector units should be checked to see if the correct quantity is installed, and the proper type used with each loop and each detector phase. When multi-channel detector units are furnished, the plans may require the provision of special cabinet wiring and an adapter harness to allow single channel detector units to be readily substituted.

10.     The prewired cabinet should also be checked for the following auxiliary equipment:

a.        A forced air ventilating fan automatically controlled by a thermostat shall be furnished.

b.        A conflict monitor shall be furnished. When the plans so specify, according to 733., an increased capability monitor shall be furnished. The minimum number of monitor channels, related to the number of phases for the intersection, should conform to 733.

c.        Load switches should be provided in sufficient quantity for the interval sequence shown in the plans. The switches shall be solid state NEMA triple-signal type with input indicator lamps. The minimum number of load switch sockets furnished, related to the number of phases for the intersection, shall conform to 733.

d.        A flasher or flashers shall be solid state NEMA type.

e.        Relays required for the proper operation of the specified equipment shall be furnished.

f.         Lightning protection devices shall be furnished for the protection of solid state controllers. They should be located on the incoming power line and on loop detector leads where these connect to the terminal block. When solid state coordinators are furnished, they should be protected by devices across each conductor and ground on the interconnect cable.

g.        A convenience outlet and lamp shall be furnished. The outlet should contain at least one standard three-wire plug receptacle of the ground-fault, circuit-interrupting type. The lamp should be an incandescent type, located in the upper part of the cabinet and controlled by a switch.

h.        A main power breaker shall be furnished. The fan, convenience outlet, and lamp should be wired on a branch of the AC+ power line preceding the main breaker, so these may be operated independently of the main breaker control. This preceding branch should contain an auxiliary breaker rated at 15 amp.

i.         A radio interference filter should be installed in the incoming AC+ power line between the main breaker and solid state equipment. If the equipment furnished does not provide signal and flasher circuit switching at the zero voltage point of the power line sinusoid wave form, filters should also be provided for the load switches and flasher.

j.         A manual control cord with push button should be furnished only when the plans so require (733). The cord should be at least 5 feet (1.5 meters) long.

k.        Switches required for the proper operation of specified equipment should be furnished and labeled as to function and setting position. The following switches should be grouped behind the small door-in-door (police door): signal shutdown switch, flash control switch, and an automatic/manual transfer switch (when manual control is specified).

l.         Terminal blocks should not be obstructed by other equipment. Terminal points should accept spade-type wiring terminals except for incoming power terminal points which may be either the type to accept bare wire or spade terminals. Contact between adjacent terminal points may be either by bus bar or by wire jumpers with spade terminals.

11.     The incoming power bus should be fed from the line side of the incoming 120 VAC power line after the circuit has passed through the main power breaker. A signal bus relay should control power to the bus which supplies power for the signal load switches. The requirement for radio interference filters (733) should be adhered to, such as buses supplying load switches and flashers being filtered if load switches do not switch at the zero voltage point of the power line sinusoid wave form. A common terminal bus insulated from the cabinet should be furnished for the connection of the neutral wire of the incoming 120 VAC power line. This common bus should have sufficient terminal points to accommodate all potential cabinet wiring as well as field wiring. A separate common terminal, insulated from the panel, should be used for the interconnect common (if interconnection is a part of the system).

12.     The cabinet should include a ground bus bar with an adequate number (at least three) of ground terminal points (733). This bus bar should be grounded to the cabinet. The ground bus bar will normally be bonded to the common terminal bus using at least a No. 8 AWG copper wire.

13.     Wiring bundles should be neatly arranged and grouped as to voltage and function and should be lashed or restrained so they do not interfere with the access to equipment, including terminal blocks or buses. The harnesses should be of sufficient length and should be easily traced through the cabinet. All conductors should be stranded, with labeled spade-type terminals or plug connectors. The wiring should be color coded, with solid white for the AC common, black for the AC line side power (AC+), and solid green or white with green stripes for the safety ground.

14.     Incoming cable and wire should be identified by tags or bands (632). The size, material, and method of tag or band identification should be in accordance with 725, except that marking may be by indelible pen on plastic tags instead of embossed letters. The identification on the tags or bands should conform to the wiring diagram for the cabinet and its intersection, with typical abbreviations in accordance with the Table in 632.

15.     Two copies of the schematic and wiring diagram for each cabinet and its intersection should be furnished by the Contractor. The diagrams are to be updated to reflect any changes made during construction. The diagrams should be neat and legible on durable paper and folded in a moisture-proof envelope fastened to the cabinet interior.

Cable and Wire Identification (632.05)

As noted in 632, cables and wires shall be identified as shown in TEM Table 497-2.

Vehicular Signal Head, Conventional (632.06)

1.        Signal heads shall conform to the plans, 732 and applicable SCD. Signal heads shall have the correct number of faces (one-way, two-way, three-way, or four-way) and each face shall be made up of the correct number of optical sections (one, three, four, or five). Sections shall be of the correct lens size (i.e., 8 or 12 inches [200 or 300 millimeters]), color, and ball or arrow configuration. Arrow lenses are only to be the 12-inch (300 millimeter) size. It should be noted that arrow lenses are made in Rights, Lefts, and Throughs (up). The use of the proper arrow lens should be checked.

2.        Lenses shall be aligned properly in their frames so their optical configuration directs most of the light to the forward sector.

3.        Signal heads shall have a yellow or black finish, unless otherwise specified in the plan.

4.        Cutaway type visors shall be fastened to each optical section, unless open bottom tunnel visors or other types are specified, and the interior finish of the visors shall be flat black.

5.        Signals should be clean and the assembly tight. Gaskets should be in good condition and lens door hinges and latches should be in good working order. All openings not used for mounting purposes shall be closed by waterproof caps.

6.        Five-section faces, arranged in accordance with applicable SCD and the plans, are to use galvanized pipe, elbows, and tubular hardware painted to match the signal head.

7.        Swinging signals shall be installed in a plumb condition. A balance adjustor should be used only when necessary to achieve plumb.

8.        Swinging signals suspended from a mast arm shall be fitted with a universal hanger which permits swinging in both longitudinal and transverse directions.

9.        When specified by the plans, disconnect hangers shall be used with signal heads.

10.     Drop pipes, 1-1/2-inch (38 millimeter) diameter galvanized pipes, are a source of trouble and are aesthetically unattractive; therefore, they are intended to be used only when they are necessary to permit signals to be suspended above the roadway within a clearance of 16 to 18 feet (4.9 to 5.5 meters). Signals supported by span wire, with sag required between 3 and 5 percent, shall be brought to proper clearance by adjusting the attachment height of the span wire to the poles. Due to the 2 foot (0.6 meter) clearance tolerance, drop pipes should not be necessary in most cases.

11.     When the plans so specify, backplates shall be fitted to signal heads.

12.     Signal cable shall be routed into the interior of heads through the entrance fitting using a grommet. The cable shall be routed to each face’s terminal block, which is typically in the yellow indication section, but may be in the green section. Conductors shall be fitted with spade-type terminals and shall be fastened securely to the correct terminal points. Conductors shall be identified according to the wiring diagram. Signal cable shall not be spliced between signals or in signal face interiors.

13.     External signal cable shall be fashioned into a drip loop extending at least 6 inches (150 millimeters) below the entrance fitting, but shall not chafe on the signal.

14.     Lamps shall be LED only.

15.     Each face of a signal head shall be oriented to its approach of traffic and its locking device securely tightened. Orientation or aiming of standard signals should be done so the maximum light intensity from a standard signal is directed slightly below the horizontal center; thus, on a level approach, the face of the signal should be essentially vertical. When an approach to a signal is on a grade, the signal may be tilted slightly to point the signal axis parallel to the grade of the approach. Horizontal aiming should orient the axis of signal display parallel to the centerline of the approach for straight approaches when the signal is over the roadway. When the approach roadway is curved, or when a signal is not over the roadway, the axis should be directed at a point on the approach which is 175 to 625 feet (54 to 191 meters) in advance of the intersection, the distance being dependent on the speed of approaching traffic.

16.     When a vehicular traffic signal head has been erected and faces approaching traffic, it shall either be in operation as a stop-and-go signal or a flasher, or it shall be covered or bagged. This is an OMUTCD requirement and cannot be ignored. Typically, the plans will contain an item for “Covering of Vehicular Signal Heads,” which will require the Contractor to cover, maintain the covering, and subsequently remove the covering when the signal is ready to commence operation.

17.     Normally, the plans will provide the covering item for each new signal head, but will not provide them for any existing heads which are to be removed. The intent is that covering will be necessary for the new heads until they, and their associated controller and wiring, have been checked by circuit testing (see 632), while any existing signals at the intersection will continue to control traffic. When the new signals are uncovered and placed in operation, the existing signals can be quickly removed. Specific maintenance of traffic requirements in any plan may require a different means to assure the unused signals are not exposed to traffic.

Vehicular Signal Head, Optically Programmed (632.07)

Programmed heads shall conform to certified drawings and the plans. They are to have the correct number of optical sections making up each face. Programmed heads have many points of similarity to regular heads. For more detailed information, see publications by the manufacturer.

Programmed heads shall be mounted in a manner permitting little or no motion. If mounted on a mast arm, a rigid adapter shall be used. Heads of more than three vertical sections mounted on a mast arm shall be fitted with pipe backbracing, as shown on SCD TC-85.20. The pipe shall be a minimum of 17 inches (430 millimeters) behind the signal center axis so that adequate clearance is provided for the programming procedure. If heads are supported by span wire, a tether messenger wire shall be attached to a fitting in the bottom of the signal’s lower section.

Customarily the manufacturer’s representative will program the signals, but in accordance with the plans, the Contractor is responsible for the correct aiming and masking of the signal so as to be visible to drivers or pedestrians only in the area indicated on the plans.

Pedestrian Signal Head (632.08)

Pedestrian signal heads shall conform to 7325, certified drawings, the plans, and SCD TC-85.10. Signals shall have the correct type of light source and lettering height in accordance with the plans.

Housings shall have a black finish, unless otherwise specified. Visors shall be fitted over each message, except one type may have the entire face protected by a flat black sunshade fastened close to the lens. The interior surface of visors shall be flat black finish. Signals should be clean and the assembly tight. Gaskets should be in good condition and lens door hinges and latches in good working order.

Housings shall be positioned with a minimum set back of 2 feet (0.6 meter) from the curb and a height of 8 to 9 feet (2.4 to 2.7 meters) above the sidewalk for adequate clearance. The heads shall be oriented toward their crosswalk and locked securely in position.

Push button housings shall have a yellow finish, unless otherwise specified. The push button shall be positioned 3-1/2 to 4 feet (1.1 to 1.2 meters) above the sidewalk.

Push buttons on metal poles shall be installed over a 3/4-inch (19 millimeters) maximum field drilled hole with edge protected by two coats of zinc-rich paint and a rubber grommet inserted.

The push button housing curved back shall be positioned over the hole, wiring routed through to the electrical mechanism, and the housing secured by stainless steel screws. Unused holes in the housing shall be plugged. Push buttons on wooden poles shall have their wiring in conduit connected to a fitting of the signal support.

Signal head supports (conduit and fittings) on wooden poles shall be grounded using a ground clamp and an insulated ground wire stapled to the pole and covered by a molding.

If specified in the plans, pedestrian signal heads may be covered in accordance with 632.

OMUTCD addresses standards for the signs used where push buttons are provided to actuate pedestrian signals. The sign legend shall conform to the plans.

Detector Loop (632.11)

1.        Slots cut into the pavement which form rectangular detection loops shall be in accordance with the plans and SCD TC-82.10.

2.        The slots shall be a minimum of 3/8 inch (9.5 millimeters) in width and shall have a minimum depth of 2 inches (50 millimeters) in concrete and 4 inches (100 millimeters) in asphalt concrete. SCD TC-82.10 requires that loop corners be made at a drilled or bored hole, about 1-1/4 inches (32 millimeters) in diameter, and with the same depth as the saw slot. Any sharp edges at the saw slots and the holes shall be chiseled out.

3.        The slot depth shall accommodate the specified number of turns of wire laid so that the uppermost wire has a covering of at least 3/4 inch (19 millimeters). The number of wire turns shall comply with the plans and the table in SCD TC-82.10. A separate slot leading from the loop to the pavement edge is typically cut for each loop.

4.        When permitted by the Engineer, loops installed in new asphalt concrete may be sawed, and the loop wire(s) embedded with sealant in a subsurface course with subsequent covering by the surface course.

5.        Some plans may specify the use of preformed loops placed on the pavement for covering by a surface course of asphalt concrete.

6.        If the problem of loop installations in brick streets is encountered, the Engineer should consult with the local traffic engineer for recommendations.

7.        Loop locations may be adjusted to avoid manholes. Loops should not be placed across pavement joints. Instead, lateral and longitudinal adjustments should be considered with the approval of the Project Engineer. If joint crossing is unavoidable or major pavement cracks are encountered, the following techniques may be used.

a.        In Technique A, the loop wires are laid over the joint or crack within a 3-inch (75 millimeter) square or circular hole cut to slot depth. The wires are laid in an “S” shape and the hole filled with elastic joint material or asphalt concrete.

b.        In Technique B, the slot at the joint or crack is saw cut to twice-normal width and depth. The wires are laid so as to conform to the deepened slot, which is injected with soft setting butyl rubber up to the depth of the original slot. The original slot depth and the remaining perimeter of the slots are embedded with standard sealant cured to a flexible state.

c.        In Technique C, the slot at the joint or crack is enlarged. The wires are encased in a length of plastic tubing which should be large enough to loosely hold all wires and may be slit lengthwise to facilitate construction. Before placing it in the slot, the ends and the longitudinal slit are to be taped shut to prevent the entry of loop sealant. The enlarged slot is then filled with loop sealant.

8.        Before loop wire is placed, all slots shall be brushed, blown clean of loose material, and completely dry.

9.        Loop detector wire shall be single-conductor No. 14 AWG insulated wire, type IMSA 51-5 with stranded copper conductors, unless otherwise specified. The wire should be marked at intervals with the wire gauge, UL label and type. The detector wire is contained inside a flexible plastic tube, as required by IMSA 51-5.

10.     The correct turns of loop wire shall be placed in the slots, to comply with 6323 and the plans. The wire shall be pushed to the bottom of the slots with a blunt wooden tool (or equivalent) to avoid damaging the insulation.

11.     The wires with tubing at the pavement edge or curb shall be led into a conduit of the size shown in SCD TC 82.10. Care should be taken to prevent excessive slack at the point where the wires enter the conduit. The high end of the conduit shall be sealed in accordance with SCD TC 82.10.

12.     The detector wire shall be twisted in the conduit leading from the pavement edge to the pull box. The flexible plastic tubing shall cover the wire completely from the splice at the lead-in cable, through the entire loop turns, and back to the splice. The tubing provides extra protection from abrasion and allows the wire to slide inside the tubing in case of pavement shift or cracks, thus minimizing the possibility of breakage. Since wire/tubing includes an air pocket, it will tend to float to the surface when sealant is applied to the slot. For this reason, it is usually necessary to wedge short lengths of the tubing, or similar devices, into the slot to wedge down the tubing/wire. These are usually needed at 1 to 2 foot (0.3 to 0.6 meter) intervals.

13.     The slots shall be completely filled with approved sealant and left undisturbed until cured to a flexible state. Sealants on the ODOT prequalified list shall be used in accordance with the manufacturer’s recommendations. Materials which set-up to a hard or brittle state are not acceptable.

14.     Detector loops are measured as “each” loop installed and the item includes wire, pavement cutting, and sealant.

Loop Detector Lead-In Cable

Unless otherwise specified, loop detector lead-in cable shall be two conductor No. 14 AWG twisted pair shielded, with a jacket of black polyethylene 0.04 inch (1 millimeters) thick minimum, and polyethylene insulation with conductors of stranded copper.

Within the pull box, loop wire ends shall be joined to the conductors of the lead-in cable by soldering and covered with insulating material. An approved, poured epoxy waterproof splice kit shall be used. It is understood that epoxy splice kits are easily damaged by freezing temperatures encountered prior to mixing. Damaged epoxy components may sometimes be recognized if either of the components has turned or is streaked milky white.

Lead-in cable shall be routed to the controller cabinet, fitted with soldered spade-type terminals, and fastened to the correct points of the terminal block. The lead-in cable’s shielding shall be grounded to the ground bus within the cabinet.

If a pull box is not specified on the plans, the splice between the loop wire and lead-in cable shall be made in the first entered pole or pedestal, except where the controller cabinet is mounted on the pole or pedestal. If the controller cabinet is mounted on the pole or pedestal, the loop wires may be routed directly into the cabinet and no lead-in cable is necessary.

Testing (632.28)

General (632.28.A)

Traffic control signal components and the entire system shall be tested, as required by various specifications, to assure proper operation before acceptance. Ground rods shall be tested for satisfactory low resistance to ground. A circuit test should be performed on all conductors to make sure there are no shorts, crosses and high resistance, or other improper connections. A cable insulation or Megger test shall be performed on all conductors to verify the integrity of the insulation covering. All traffic control equipment in the controller cabinet should be checked for correct settings and all controls manipulated for assurance of an operable system.

Finally, the traffic control system shall successfully pass a 10-day performance test, which will give an opportunity for any hidden flaws to reveal their presence. As a final “housekeeping” check, equipment should be observed for any evidence of unattached ground wire, unlatched or unbolted doors, etc.

The results of the various tests are to be entered by the Contractor on test report forms (TEM Form 496-6) as required by 632.

Ground Rod Test (632.28.B)

All ground rods shall be tested by the Contractor for earth resistance to ground, as required by 632.

Short-Circuit Test (632.28.C)

Before the performance of any cable insulation (Megger) test or the 10-day performance test, a short-circuit test shall be performed by the Contractor using a volt-ohmmeter or other approved instrument. Short-circuit tests shall be conducted with all electrical loads, power sources, equipment grounds, and earth grounds disconnected (see TEM Figure 498–28).

Signal cable routed to signal heads may be tested with connection made to the lamp sockets, but without the lamps being installed.

Each conductor shall be measured against every other conductor and ground to ensure that no short-circuits, cross-circuits, or other improper connections exist. Continuity should not exist between any conductor and any other conductor including ground.

Circuit Continuity Test (632.28.D)

Each circuit branch shall be disconnected and tested by the Contractor for continuity by temporarily jumpering each branch at its termination and measuring the temporarily looped circuit for assurance that no open circuits exist (TEM Form 496-6). This testing is illustrated in TEM Figures 498-29 through 498-32. Each circuit branch should be according to plan, with no high resistance connections and with proper identification.

Lead-in cable for loop detector wire shall be tested before and after the cable is spliced to the loop wire.

Circuit continuity of signal cable may be done by applying 120 volts to each outgoing circuit and observing that only the specific lamps are lighted.

Cable Insulation Test (Megger Test) (632.28.E)

This testing is illustrated in TEM Figures 498-33 and 498-34.

1.        Each conductor of cable or wire terminating at the controller cabinet shall be tested by the Contractor for insulation resistance measured to ground (TEM Form 496-6). A listing of the resistance reading for each conductor is to be included in the test results furnished to the Engineer.

2.        Cable and wire insulation can be faulty, but the imperfections can be easily overlooked, leading to eventual electrical failure of the wiring. Weakening of insulation properties may be caused by poor storage conditions and stress due to rough handling during installation. Dirt is especially troublesome since it is an electricity conductor and can penetrate small cracks in the insulation.

3.        Insulation testing shall be performed with all conductors disconnected from their points on the terminal block in the cabinet. This will ensure that there is no voltage present and will prevent damage to any connected equipment. One Megger instrument terminal shall be attached to a termination of jumpered together ends of conductors or to the end of a single conductor cable or wire undergoing testing. The other Megger instrument terminal shall be attached to the cabinet ground bus bar.

4.        Insulation resistance shall be measured for the wire of roadway loops after the embedding of the wire with sealant in slots.

5.        The meter pointer of the Megger instrument (or equivalent indication) should be adjusted to zero and the test switch activated. Test duration should be as recommended by the instrument manufacturer.

6.        The insulation resistance measured to ground for each conductor shall be no less than 10 megohms. Cable or wire not meeting this reading shall be replaced.

7.        After completion of the cable insulation test, all cabinet wiring shall be connected in accordance with the wiring diagram. The Contractor shall demonstrate to the satisfaction of the Engineer that all circuits are continuous and operating correctly, free from shorts, crosses, and unintentional grounds.

Functional Test (632.28.F)

Before energizing the traffic signals the following functional checks should be made:

1.        The incoming AC voltage should be checked.

2.        Operation of the following equipment should be checked: cabinet ventilating fan, fan thermostat, and convenience outlet with lamp (when furnished). The filter(s) used with the fan should be unobstructed.

3.        Timing settings on solid state controllers should be varied over their ranges and all functions activated to verify that the controls are operable without fault.

4.        Timing settings in accordance with the plans should now be entered on the controller, time clock, etc. and checked for corrections. On some projects, timing settings will be provided by the maintaining agency and not listed in the plans.

5.        An agreement should be reached with the Contractor and the maintaining agency on the procedure which will be followed in the event of a signal failure prior to acceptance.

6.        Before signals are energized to control traffic, the maintaining agency should be notified and given an opportunity to check the installation and timing settings.

After energizing the traffic signals the following functional checks should be made. In the event the signals are controlling traffic at the time, these checks should be made with caution to protect the safety of workers, pedestrians and drivers.

1.        The function of all cabinet switches should be checked, including the power on/off switch and manual control (when furnished).

2.        The traffic signals and controller indicator lights should be observed to verify that the controller is timing consistently the intervals and phases set into the controls. A stopwatch is suggested, especially to check critical short intervals. All controllers’ functions should be activated to verify that operation is proper.

3.        The detector units should be investigated to determine which pavement loop(s) or other type sensor is associated with which unit. The visual indication of units (light, meter, etc.) should be observed to determine that each vehicle (truck, car, motorcycle, etc.) entering sensor areas are properly detected on the associated unit and that no extraneous calls occur when the sensor area is vacant. When a detector unit is set for "presence," a detection call should continue as long as a vehicle is positioned over the associated sensor. Concurrent with detection, the appropriate controller indicator light should exhibit the detection.

4.        The flasher switch should be activated to cause the signal heads to flash. Their indications should be checked to verify if they are correct. The flasher switch should then to be returned to the normal or signal mode and a check made of the resumption of normal stop-and-go operation.

5.        The conflict monitor should not be activated by normal signal operation or by the manipulation of cabinet switches. If at any time the monitor is activated, the Contractor is required to determine the cause of the problem and make appropriate changes and adjustments before beginning the 10-day performance test. The Contractor should test the conflict monitor by artificially causing a number of different conflicting indications. The Contractor should check that at each test, the monitor causes the signals to flash and places the controller in a "stop timing" mode. Artificial conflict may be caused by touching a jumper wire between two load switch outputs that would signal a traffic conflict. Other methods of artificially caused conflicts may be used at the discretion of the Contractor.

6.        Signals which are interconnected should be observed to determine if offset relationships are maintained in accordance with settings during all periods of the day.

7.        When preemption equipment is furnished as part of the cabinet installation, the proper functioning of the equipment should be checked. The equipment should be activated and observations made to determine if the required sequence of intervals and phases is called for in a correct and safe manner.

8.        On projects having equipment furnished for future use only, the equipment should be checked to verify that it is properly installed and operable in a correct manner.

Some signal control equipment, such as time clocks or switches and weekly programmers, are intended to vary the timing patterns at different periods of the day or days of the week. To determine if these required changes are occurring at the proper times, it is necessary that observations be made to check the operation at transition times over a period of several days.

The change in timing shall not be extremely drawn out or abrupt. The accuracy of time clocks and weekly programmers should be checked. Programmed changes should occur within 5 minutes of scheduled times for clocks of the electromechanical type and within 1 minute for clocks of the solid state type. No significant cumulative clock error should be noted during the 10-day performance test.

After successful completion of the 10-day performance test, and after a partial or final acceptance of a project, the Contractor should give the Engineer all manuals, diagrams, instructions, guarantees, and related material, as required by 632. It is recommended that the Engineer list this material in the project diary as a permanent record of the transfer. The Engineer should transfer the material to the maintaining agency. For ODOT-maintained signals, the material should be given to the District Roadway Services Manager.

After a traffic control system project has been accepted by ODOT, the Engineer should immediately notify the maintaining agency to indicate that as of a specific time and date, the agency is responsible for the operation and maintenance of the system.

Performance Test (632.28.G)

Before acceptance of the traffic control system, the Contractor shall furnish all personnel and equipment required to successfully operate the system continuously for 10 consecutive days without major malfunction or failure (632).

At least 7 days prior to the beginning of the performance test, the Contractor shall notify the Engineer of the starting date. The Engineer will notify the maintaining agency.

The Contractor shall arrange with the utility supplying the power for purchase of the energy required to conduct the test. All costs of personnel, equipment, electrical energy, and incidentals required to perform the test are to have been included in the contract unit prices for the respective items tested.

Minor failures, such as lamps, a single detector, or an individual signal head, etc. shall be immediately replaced or repaired and will not cause restart of the test.

A major malfunction or failure, such as a master or local controller, interconnect equipment, etc. will cause termination of the test, and after replacement or repair of the malfunctioning or failed equipment, the beginning of a new 10-day test.

Items which have been repaired or replaced are to be monitored by the Contractor for a period of 10 days to assure their reliability.

The complete test results are to be furnished to the Engineer on test reporting forms in accordance with 625. The Contractor is to record, in the test results, the beginning and end of the test and the method and date of the correction of each fault.

The Engineer should record the following events in the project diary: the date the 10-day performance test began, a day-by-day record of faults as they occur during the test, and the date of the successful completion of the performance test.

Final Signal Installation Check

After all wiring is completed, and all testing completed and accepted, a final inspection of the traffic control system should be performed to assure a neat and workman-like appearance.

1.        All spare conductors should be connected to the ground bus bar in the controller cabinet.

2.        All ground wires should be properly connected.

3.        The spade type ends of conductors should be sound. After all testing is completed they should be reinstalled on their correct points of terminal blocks and tightened.

4.        A visual check should be made for any signs of arcing, melted insulation, etc.

5.        All debris from wiring work or packaging materials should be cleaned from the bottom of cabinets.

6.        Cabinet vents should be checked to assure that they are unobstructed and all filters should be clean and in place.

7.        Duct sealing material shall be used to seal the conduit entering the cabinet from the base.

8.        All doors on the optical sections of vehicular and pedestrian signal heads shall be closed and latched.

9.        No wires or cable should be visible under the base plates of poles and pedestals.

10.     The handhole covers on poles and end-frames shall be securely fastened.

11.     Pedestals with transformer type bases shall have the access door securely fastened.

12.     The covers on pull boxes shall be securely bolted.

Documentation Requirements - 632 Traffic Signal Equipment

1.        Review certified drawings prior to work commencement.

a.        Document depth and width of cut for detector loop wire in pavement.

                                                               i.      Cuts blown clean.

                                                              ii.      What kind of material used to fill cuts after loop placement?

b.        Foundations.

                                                               i.      Excavate as per 503.

                                                              ii.      Perform concrete work as per 511.

                                                            iii.      No load applied for 14 days, 7 days with beam break of 650 pounds or more.

c.        Document each type of equipment installed as per certified drawings provided by supplier and as per individual specifications included in 632.

2.        Test as per 632.

3.        Measure and pay per 632.

Documentation Requirements - 633 Traffic Signal Controllers

1.        Review certified drawings prior to starting work.

a.        All electrical parts of sufficient capacity and marked per 633.

b.        Diagrams and manuals furnished to Engineer before installation.  Documents modified upon completion of work.

                                                               i.      Controllers tested and pre-qualified.

                                                              ii.      Individual items provided and documented.

                                                            iii.      Test in accordance with Item 632.

                                                            iv.      Measure and pay as per 633.

                                                              v.      Record serial numbers and manufacturing date for all LED signal lamps installed in the project.

632/633 Supplemental Information

Please refer to the Traffic Engineering Manual (TEM) for a complete list of forms, supplementary information, and updates.

 Figure 632.H – Exothermic Weld

Figure 632.I – Vehicular Signal Heads

Visors for Signal Heads

Figure 632.J – Pedestrian Signal Heads

 Figure 632.K – Loop Detector Placement and Installation

Loop Perimeter

 feet            (meters)

Number of Turns

40

(less than 12)

4

40-160

(12 to 49)

3

over 160

(over 49)

2

Figure 632.L – Loop Construction

Figure 632.M – Loop Detector Slots and Wiring

Figure 632.N – Loop Detector Slots and Wiring

Figure 632.O – Loop Detector Wiring

Figure 632.P – Magnetometer Probes and Lead-In

Figure 632.Q – Ground Rod Testing

Figure 632.R – Short-Circuit Test

Figure 632.S – Circuit Continuity Test of Loop Wire

(Before Splice to Lead-In Cable)

Figure 632.T – Circuit Continuity Test of Loop Wire and Lead-In Cable

Figure 632.U – Circuit Continuity Test of Signal Cable Disconnected from Heads or Other Cables such as Interconnect and Loop or Magnetometer Lead-In

Figure 632.V – Circuit Continuity Test of Signal Cable with Cable Connected to the Signal Heads and Lamps Installed

Figure 632.W – Cable Insulation Test (Loop Detector Wire)

 Figure 632.X – Cable Insulation Test (Signal Cable)

Figure 632.Y – SCD TC-81.20 Signal Support Design Chart

Figure 632.Z – Plan Details for Strain Poles

Figure 632.AA – Plan Details for Signal Supports - Arm Lengths

(Table is continued in Figure 632.BB)

Figure 632.BB – Plan Details for Signal Supports - Mast Arm Orientation

(Table continued from Figure 632.AA)

638 Water Mains and Service Branches

Documentation Requirements - 638 Water Mains and Service Branches

1.        State that materials conform to 638.02.

2.        Document clearance between pipe and walls of trench: 6 inches (15 cm) minimum, 12 inches (30 cm) maximum. Ensure proper clearance between water line and any utility crossing or underground structure.

3.        Grade shaped to receive bell.

4.        Type of sheeting and bracing used to support and protect adjacent utilities.

5.        Type and thickness of bedding.

6.        State that trench was kept free from water.

7.        State that pipe was carefully handled.

8.        Tracer tape installed 1 foot (0.3 m) above top of pipe extending full-length.

9.        Joints installed according to manufacturer’s recommendation.

10.     Perform and document backfill as per 611 Type B and C conduits.

11.     Document hydrostatic testing and disinfection as per 638.09 and 638.10.

12.     Measure as per 638.19 and 638.20.

640 Pavement Markings

641 Pavement Markings – General

This information is intended to serve as a guide for construction personnel where the Contractor furnishes and installs traffic control marking devices. This information may also be useful for maintenance personnel performing the same functions.   

As per 641.06, the Contractor shall establish reference points to ensure proper placement of restored markings on projects where resurfacing or other operations will result in obliteration of the existing pavement markings.

Please refer to the Traffic Engineering Manual for a complete list of forms and supplementary information. Updates are available on the following ODOT website:

http://www.dot.state.oh.us/Divisions/Operations/Traffic/publications2/TEM/Documents/Part_03_Complete_042012Revision_bookmarked_042012.pdf

Pavement Marking Materials (641.02)

Pavement marking materials used on the construction projects shall be as listed on the Approved List.

The Approved List for pavement marking materials is maintained by the Office of Material Management (OMM) and is available on the website.

http://www.dot.state.oh.us/Divisions/ConstructionMgt/Materials/Pages/PAVEMENT-MARKING-MATERIALS.aspx

The appropriate type of glass beads shall be applied according to C&MS 740.09 for different types of pavement marking materials.

Application of Pavement Marking Materials (641.03)

Pavement marking materials shall be applied according to C&MS Items 640 and 740.

Data Logging System (DLS) (641.04)

The Data logger System can be verified in the field by using the following method:

DLS Verification Testing

This section provides information on the Data Logger System (DLS) for long-line striping trucks, the reports generated by DLS, and how to use the reports to verify compliance with specifications.

DLS Requirements

The requirements for DLS are contained in C&MS Section 641.04.

According to Item 641.04, long-line striping equipment for traffic paint, polyester, epoxy, and work zone markings (Item 642) shall be equipped with a computerized Data Logger System (DLS) to document long-line markings as follows:

1.        Measure and record application vehicle speed to nearest 0.1 mph.

2.        Measure and record weight and/or volume amount of material used by color.

3.        Measure and record weight of glass beads.

4.        Measure and record pavement surface temperature.

5.        Measure and record air temperature.

6.        Measure and record dew point.

7.        Measure and record humidity.

8.        Calculate and record average material application rates and film thickness over the section painted.

9.        ODOT provides standard DLS spreadsheets which prescribe the correct DLS report format and content.

DLS are not required for any markings applied by hand, with push carts, for channelizing lines, or Class II work zone markings.

When the Striping Truck Arrives on the Project

·         Each district should establish one individual as District DLS Contact to receive DLS Reports for all striping activities. Check with the District Construction Office for the email address of the District DLS Contact to provide to the Contractor.

·         Make sure every vehicle in the striping train has the correct maintenance of traffic equipment and signs. See SCD MT-99.20 and plan notes.

·         Check the driver’s door or the door of the DLS unit to confirm the presence of the DLS calibration sticker. It should be signed and carry a date no more than one-year-old. Every DLS must be calibrated once every year.

·         Make sure that there are adequate TE-24s to cover all materials needed for the job.

·         Make arrangements with the Contractor’s crew foreman to get DLS Short Reports for each day’s work. DLS Short Reports are to be provided to ODOT the next working day or, when requested by ODOT personnel, any time route sections are completed on any given day. ODOT should receive a report from the Contractor for each day worked. The DLS specification requires the Contractor to furnish ODOT with a paper copy of the DLS Short Report which should be retained to compare to the electronic file that will be received later.

·         The Data Logger System shall be verified by field personnel.  Field personnel shall randomly verify the components of the DLS.  The purpose of this is to verify that the striping truck places the material shown on the DLS printout.  Field personnel should try to verify the DLS of every paint contractor at least once per construction season.  If field personnel believe that the DLS printouts are not accurate, then more field checks can be taken.

How to Field Verify the Data Logger System

Figure 640.A – Striping Truck with DLS System

Figure 640.B – Electronic Control Box

Figure 640.C – Sensors

Sensors such as temperature sensors, located at appropriate locations on the striping truck, provide temperature data.

Figure 640.D – Gauges

Gauges provide data and help monitor the temperatures of striping material in the tanks.

Figure 640.E – Glass Bead Tank Load Cells

Glass bead tanks are mounted on load cells.  Load cells are the basis of bead weight calculations.

Figure 640.F – DLS Electronic Data Sheet

1.        DLS data is automatically recorded and stored electronically. 

2.        DLS data includes:

a.        Sensor data.

b.        Distance data.

c.        Ambient conditions.

d.        Material quantities.

3.        Verification test results will be compared to the Contractor’s electronic sheet data.

Calibration Sticker Check

Check for the presence of the annual calibration sticker.

Figure 640.G – Calibration Sticker

Evidence of the annual calibration shall be a signed and affixed sticker to the inside of the driver’s door of each striping truck.

Yearly Calibration

1.        As per C&MS 641.04, each DLS shall have an annual calibration.

2.        Items to be calibrated include:

a.        All mechanical and electrical components.

b.        Software.

c.        Function and output.

3.        Calibration will be confirmed by the manufacturer.

The Plate Test

Figure 640.H – The Plate Test

1.        Place an aluminum plate, approximately 24 inches by 8 inches under the paint gun of the striping truck. Aluminum plates are supplied through the Office of Materials Management (OMM), Chemical Section.

2.        Allow the striping truck to stripe over the plate in order to get a stripe of the desired thickness on the plate.

3.        Send the striped plate to the OMM, Chemical Section for film thickness testing.  After converting dry film thickness to wet film thickness, the difference obtained from the plate should be no more than 5 percent from the DLS reading.

4.        Send the Contractor’s DLS average mils applied data as comparison for the film thickness testing results. See picture below.

5.        Note: Be careful not to damage the paint stripe on the plate.

Figure 640.I – Average Mils Applied

The Bead Weight Test

Figure 640.J – The Bead Weight Test

1.        Check and record the bead weight on the DLS electronic data sheet W1.

2.        Obtain an object of known weight. Must be a minimum of 20 pounds (e.g., a 50 pound bag of glass beads).

3.        Place the weight on top of the bead tank. Keep the weight in position on top of the tank and check and record the new weight, W2, on the DLS electronic data sheet.

Subtract W1 from W2 to get the known weight of the object used.

W2 – W1 = weight of the object of known weight used.

Correct test results confirm the proper operation of the bead tank load cells as well as the accuracy of the data on the spreadsheet.  The difference should be no more than 5 percent.

Figure 640.K – The Bead Weight Test

The Infrared Thermometer Test

Figure 640.L – The Infrared Thermometer Test

Use a hand-held Infrared Thermometer to measure road surface temperature, air temperature, and/or striping material temperature.

1.        To operate the infrared thermometer, follow the manufacturer’s operating procedures.

2.        Compare temperature readings to the data on the appropriate DLS electronic screen.

3.        Temperature readings on the DLS screen should be within ±5 percent of the thermometer readings.   

Figure 640.M – The Infrared Thermometer Test

The Humidity Test

Figure 640.N – The Humidity Test

1.        Measure the ambient humidity with the use of a sling hydrometer.

2.        To operate the sling hydrometer, follow the manufacturer’s operating procedures.

3.        Compare humidity readings to the data on the appropriate DLS electronic screen.

4.        Humidity readings on the DLS screen should be within ±5 percent of the hydrometer readings.   

Figure 640.O – The Humidity Test

The Distance Traveled Test

Figure 640.P – The Distance Traveled Test

1.        Testing the distance traveled data on the DLS electronic data screen can be done using a distance wheel like the one shown in the picture.

2.        To operate the distance wheel, follow the manufacturer’s operating procedures.

3.        Compare distance readings to the data on the appropriate DLS electronic screen.

4.        Distance readings on the DLS screen should be within ±5 percent of the distance wheel readings.

5.        DLS distance data can also be checked using mile markers and an accurate odometer. 

Figure 640.Q – The Distance Traveled Test

Summary

1.        The specified annual calibration of the data logger system is the primary check of the operation of the systems.

2.        The tests described above are meant to be done in a random fashion to:

a.        Verify proper operation after calibration.

b.        Verify correct millages are applied.

c.        Determine if the system is the cause of suspicious developments in the field application of striping material.

3.        One or all of the tests may be used to check the DLS operation.

What to Do When the DLS Fails         

If the DLS fails during the day, allow the Contractor to complete the day’s work and document the application quantities. Make the calculations for gallons of material per mile and pounds of beads per 100 square feet from the quantities used, provided by the Contractor, with your confirmation of accuracy. The Contractors are expected to repair the DLS before resuming work. See C&MS Section 641.04, paragraph three.

If you have any significant issues regarding DLS use, please call Dan Groh at Central Office Construction, (614) 387-1162 or Maria Kerestly at the Office of Material Management, (614) 275-1349 for further assistance.

DLS Reports

The DLS Report is an Excel spreadsheet which contains data on environmental conditions and material application parameters recorded during striping operations.

                            ODOT has developed standard DLS Reports for four different types of striping trucks:

·         Weight-Based DLS – for pressure tank trucks (CA-T-1, CA-T-2)

·         Stroke-Based DLS – for pumper trucks (CA-T-3, CA-T-4)

·         Flow-Based DLS – for either type, but using material flow meter (CA-T-5, CA-T-6)

·         Thermoplastic DLS – for thermoplastic trucks. Note: the thermoplastic DLS is an abbreviated report, as we cannot yet measure material used, although beads used and environmental conditions are recorded (CA-T-7, CA-T-8).

Two versions of the DLS Report are contained in each Excel file:  DLS Short Report and DLS Full Report. The DLS Short Report is an abbreviated format containing only critical application information which can be easily printed on an 8.5 inch by 11 inch paper using in-truck printers. DLS Full Reports contain all project, application, and environmental data.

Delivery of DLS Reports

Each district should establish a District DLS Contact person who will receive email copies of the DLS Reports and provide that person’s name and email address at the preconstruction meeting.

The paper copy of the DLS Short Report covering all route sections completed each day must be provided to ODOT personnel the next working day. A paper copy of the DLS Short Report may be requested from the Contractor by ODOT personnel at any time during striping operations for those route sections completed so far that day. The paper copy of the DLS Short Report should be retained by the project and compared to the DLS Full Report for the same route sections, which will be provided to ODOT personnel by the Contractor at a later time, as described below.

DLS Full Reports contain all project, application, and environmental data and can be provided to ODOT by any one of the following methods, which should be agreed upon at the preconstruction meeting:

·         Hand delivery of paper report.

·         Fax delivery of paper report.

·         E-mail an electronic version of the Excel spreadsheet file.

Within two weeks of the application date of the markings which require documentation with the DLS, the Contractor is required to furnish the District DLS Contact with an electronic version of the Excel spreadsheet file of the DLS Report in ODOT standard DLS Report format by e-mail at the e-mail address provided at the preconstruction meeting. Note: This file will contain both the DLS Full Report and the DLS Short Report on separate sheet tabs.

At the end of the project, the Contractor is required to furnish the District DLS Contact with all DLS Excel spreadsheet files in ODOT standard DLS Report format. Note: This file will contain both the DLS Full Report and the DLS Short Report on separate sheet tabs.  The Engineer shall forward the final electronic copy containing the DLS Long report and the DLS short report to the following address:

DLS.Report@dot.state.oh.us

DLS Report Security

ODOT has established a method to monitor accuracy of DLS Reports. This method is based on comparison of the paper copy DLS Short Reports for daily production to the DLS Full Report for the same day. Note: The DLS Short Report does not contain all project or environmental information, but does contain all information necessary to monitor correct application rates and speed.

The Contractor is required to provide ODOT personnel with a paper copy of the DLS Short Report for each day’s production the next working day. ODOT personnel may also occasionally request a copy of the DLS Short Report during the day for those route sections completed thus far that day. On projects with only partial days of striping work, ODOT personnel should request the DLS Short Report immediately after the Contractor finishes the striping operation. Printing of the DLS Short Report soon after completion of the striping operation will minimize the opportunity for tampering.

ODOT will keep these paper reports and compare them to the DLS Full Report that is received later. Any differences in sections, lengths, quantities, or application rates between the Short Report and Full Report should be considered suspect and will be investigated more closely. There should be no valid reason for any differences between these reports beyond the complete listing of route sections between partial day and full day reports.

Pay Items

Pay items are plan quantity. If there is a significant variance between the actual and plan quantities, meet with the ODOT project personnel to address the issue. Please note that per C&MS Section 641.12, Method of Measurement, pavement markings are designed, measured, and paid “end-to-end,” including gaps, intersections, and other sections of pavement not normally marked. This provision applies to all types of roadways and lines.

The DLS is used for two purposes, neither of which is to measure pay item quantities:

1.        To monitor environmental conditions and material application parameters, such as temperatures.

2.        To monitor actual application rates of marking materials and glass beads for purposes of determining deficiencies in accordance with Section 641.11.

How Data Is Entered into DLS Reports

Each report has three different types of cells which are color-coded: 

1.        One type contains data which may be manually entered during striping operations (yellow). Note that this information may also be entered into the job screens of the DLS console and come into the Report without additional manual entry.

2.        One type contains data which must come directly from the DLS (green).

3.        One type contains values that are calculated by the spreadsheet (rose) from data provided by the DLS.

The DLS Short Report and the DLS Full Report will have one row for each section painted, by route and by direction, even if the section length is less than 10 miles. (A route section is a continuous section of highway without breaks, with the same route number designation in one direction of travel.) A new route section is not started at 10 miles if the route and direction stay the same even when the section length exceeds 10 miles. Whenever material or beads are loaded, the route section is ended. Start a new route section, for that route, to complete the route or, if needed, until reloading.

Depending on how the Contractor sequences work, the route sections will generally match the plan sub-summary.

How to Read a DLS Report

The Contractor is required to provide a DLS Short Report for each day’s work. It should be furnished to the project the next working day after striping occurs. A paper copy of the DLS Short Report is printed from an in-truck printer each day or upon demand of ODOT personnel. This copy should be compared to the DLS Full Report, which is provided to the District DLS Contact person within two weeks of application.

Check General Project Information

Check the date box in upper left corner for correct information. Note that the yellow color indicates manual entry.

Check crew names and day’s production boxes in center and right upper parts of report.

Next, check to make sure each cell in the body of the report contains data. There should be a row for each route section, by direction, striped. Start with the yellow columns on the left side. Note: The rose color indicates a value calculated by the spreadsheet. Manual entry of values in rose colored cells is not permitted.

Then, check the yellow columns on the right to confirm that the correct material and bead batch numbers have been entered. These should be supported by TE-24s.

All of the above information is manually entered into either the report or the DLS console and is the same for Section 614, Class III markings using 740.02 paint, 642, 643, 644, and 646 materials, for all types of trucks and for all types of DLS.

Check for proper material application rates – varies by type of material:

 For Section 614, Class III markings using 740.02 paint, 642, 643, and 646 materials only:

Review the application thickness (which is the average mil thickness over the section), distance painted (linear feet from gun counters and equivalent miles painted calculated by spreadsheet [linear feet/5280]), gallons used, and gallons per mile applied (gallons used/equiv miles painted). Compare the actual gallons per mile applied to the requirements in Section 614.11, 642.04, 643.04 or 646.05. Determine any deficiencies per Section 641.11. Note: The green color indicates values which come directly from the DLS and rose color indicates values calculated by the spreadsheet. Manual entry of values in these cells is not permitted.

For Section 644 materials only:

Present technology does not permit measuring the material usage of hot thermoplastic. Determine pounds per mile from field measured amount of material used and the equivalent miles painted from the DLS report. Determine any deficiencies per Section 641.11.

Check for proper glass bead application rates – the same for all materials:

Check the weights of beads used and the actual pounds per 100 square feet (weight of beads used/100 square feet of markings applied). The spreadsheet divides the sum of pounds of beads used, by the linear feet painted, multiplied by line width in inches, divided by 12 inches, divided by 100.

Compare the actual pounds per 100 square feet applied to the requirements for Section 614.11, Class III, 642.04, 643.04, 644.04, or 646.05. Determine any deficiencies per Section 641.11.

Check the average speed of application:

Check to confirm the material temperatures and environmental conditions have been recorded:

The average material temperatures and environmental conditions over the section painted are recorded in the remaining green columns. These values are the average of all readings recorded over the section painted. There are slight differences between DLS types.

Most sprayed materials (paints, polyester, and epoxy) can be heated slightly to improve flow and spraying characteristics. ODOT does not specify minimum or maximum temperatures, but defaults to those recommended by the material manufacturer.

Thermoplastic materials have temperature requirements for both pavement and air temperatures and material temperatures. See Section 644.04 for specific requirements. These values are the average of all readings recorded over the section painted.

Kettle temperature cannot exceed 450 °F and material at point of application must be between 400 °F and 440 °F. If thermoplastic material is overheated in the kettle or applied below 400 °F, it will not perform as intended and should be considered unsatisfactory and must be replaced per Section  641.11 and 644.05.B. Thermoplastic applied when pavement and air temperatures are below those specified in Section 644.04 will not bond adequately to the pavement and applications should not be made under those conditions.

Check to confirm the weight per gallon (for liquid materials – all DLS types) and stroke information (for stroke-based DLS) has been recorded:

Weight per gallon, per batch, is entered into the DLS console during job setup for liquid materials for all DLS types and reported here as recorded data. Note the weight per gallon may vary per batch.

For stroke-based DLS only, stroke calibration is entered into the DLS console during setup and reported here as recorded data. The number of strokes is recorded during striping. This information is used by the DLS to calculate gallons used.

If You Need Further Assistance

Should it be necessary, please contact Dan Groh at Central Office Construction, (614) 387-1162 or Maria Kerestly at the Office of Material Management, (614) 275-1349 for further assistance.

Construction Inspection during Pavement Marking Installation

Before the application of marking material, pavement surface should be clean and dry by using:

1.        Power broom.

2.        Air jets (guns).

Approve the pre-marking for long lines and auxiliary markings to ensure proper layout placement.

Center lines shall be “T” marked to establish no-passing lines.

Figure 640.R – Example of Premarking

District shall provide center line paint logs.

As per Item 641.06, the Contractor shall establish reference points to ensure proper placement of restored markings on projects where resurfacing or other operations will result in obliteration of the existing pavement markings.

Figure 640.S – Example of Measurement of Markings

Marking lines shall be applied to the width specified, ±1/4 inch.

Pavement markings shall be free of uneven edges, overspray, and other visible defects.

Figure 640.T – Example of Uneven Edge Line Placement

Pavement marking lines shall be placed as per SCD TC-73.10 as follows:

1.        Edge lines shall be applied 6 inches from the pavement edge.

2.        Lane lines shall be applied 2 inches to left of joint.

3.        Center lines shall be applied 2 inches from joint.

Pavement marking lines shall be straight or smoothly curved true to the alignment of the pavement.

1.        If deviation is greater than 3 inches in 100 feet, it shall be corrected.

Gaps shall be filled that were not marked as a result of template use for spray-applied auxiliary markings with marking material after the template is removed.

1.        For extruded thermoplastics, gaps may be left.

Figure 640.U – Example of Retroreflectivity Check

Pavement marking lines shall be sharp, well defined and uniformly retroreflective.

1.        To check for retroreflectivity, put sun over shoulder.

2.        If it is not sunny:

a.        A well beaded line in the daylight will appear dull.

b.        An unbeaded line will be shiny.

3.        If possible, review lines at night for retroreflectivity.

642 Traffic Paint

1.        Material Type, 740.02.

a.        Traffic Paint Type 1, fast dry, water-based paint.

b.        Traffic Paint Type 1A, fast dry, water-based paint for cold weather conditions.

2.        Glass beads, 740.09 Type A. 

3.        Application of Traffic Paint, Item 642, Type 1 and 1A.         

a.        Traffic Paint Type 1 shall be applied when the pavement and air temperature are 50 °F and above.

b.        Traffic Paint Type 1A shall be applied when the pavement and air temperature are between 35 °F and 50 °F.

c.        Glass beads, 740.09 Type A shall be applied at the rate of 15 pounds per 100 square feet of Type 1 traffic paint applied.

d.        Glass beads, 740.09 Type A shall be applied at the rate of 8 pounds per 100 square feet of Type 1A traffic paint applied.

e.        Type 1 Traffic Paint shall be applied at the rate of 22 gallons per mile of 4-inch solid line, 33 gallons per mile of 6-inch solid line, and/or 1.25 gallons per 100 square feet.

f.         Type 1A Traffic Paint shall be applied at the rate of 16 gallons per mile of 4-inch solid line, 24 gallons per mile of 6-inch solid line, and/or 0.94 gallon per 100 square feet.

g.        Striper equipment speed shall be according to the paint manufacturer’s recommendations.

h.        Coning of line required because pavement marking is not track free in 2 minutes or less.

Documentation Requirements - 642 Traffic Paint

1.        General requirements per 641.

2.        Material as per 740.02 and 740.09, SS 1047 and SS 1089.

3.        Temperature above 50 °F for Type 1.

4.        Temperature between 35 °F and 50 °F for Type 1A.

5.        Location and/or stationing of where work is performed.

6.        Measure in appropriate unit and turn in for pay.

7.        Use form CA-D-3A to document information.

643 Polyester Pavement Marking

1.        Material Type, 740.03.

2.        Glass beads, 740.09 Type B.

3.        Application of Polyester, Item 643.

a.        Polyester shall be applied when the pavement and air temperature are 50 °F and above.

b.        Polyester shall be applied in two components (catalyst and resin) in proportions recommended by the manufacturer.

c.        Glass beads, 740.09 Type B shall be applied at the rate of 16.5 pounds per 100 square feet of polyester used.

d.        Polyester shall be applied at the rate of 16 gallons per mile of 4-inch line, 24 gallons per mile of 6-inch line, and/or 0.94 gallon per 100 square feet.

e.        Striping equipment speed shall be not less than 7 miles per hour (11 km/hr).

f.         Dry time is 45 minutes and less.

                                                               i.      Coning is required to protect the line until track free.

                                                              ii.      If tracking continues after 45 minutes, cease marking operation until tracking problem is corrected.

Documentation Requirements - 643 Polyester Pavement Marking

1.        General requirements per 641.

2.        Material as per 740.03 and 740.09, SS 1047 and SS 1089.

3.        Temperature above 50 °F.

4.        Location and/or stationing of where work is performed.

5.        Measure in appropriate unit and turn in for pay.

6.        Use form CA-D-3A to document information.

644 Thermoplastic Pavement Marking

1.        Material Type, 740.04.

2.        Glass beads, 740.09 Type C.

3.        Application of Thermoplastic, Item 644.   

a.        Thermoplastic shall be applied to pavements less than a year old when the pavement surface and the air temperature are 50 °F or more. 

                                                               i.      At the end of the construction season, if the surface temperature is 50 °F or less, apply Traffic Paint Type 1A.

b.        Thermoplastic shall be applied to pavements one year or older when the pavement surface and the air temperature are 70 °F or more.

c.        At the point of application, the temperature of thermoplastic shall be at least 400 °F, but no more than 440 °F.

d.        Glass beads, 740.09 Type C, shall be applied at the rate of 12 pounds per 100 square feet.

                                                               i.      Thermoplastic material shall be applied at a thickness of 125 mils.

                                                              ii.      Use an applicator that has a shoe which rides on the pavement and extrudes the thermoplastic.

e.        Thermoplastic shall be applied at the rate of 2,340 pounds per mile of 4-inch line, 4,680 pounds per mile of 6-inch line, and/or 133 pounds per 100 square feet.

Documentation Requirements - 644 Thermoplastic Pavement Marking

1.        General requirements per 644.

2.        Material as per 740.04 and 740.09, SS 1047 and SS 1089.

3.        Air and pavement temperature, type and condition of existing pavement.

a.        Temperature requirements are outlined in 644.04.

4.        Location and/or stationing of where work is performed.

5.        Measure in appropriate unit and turn in for pay.

6.        Use form CA-D-3A to document information.

645 Preformed Pavement Marking

1.        Material Types, 740.05 and 740.06.

2.        Type A, Item 740.05, shall be used for permanent markings.

a.        Type A1 material, 0.090 inches thick, shall be applied with a pre-coated adhesive layer.

b.        Type A2 material, 0.060 inches thick, shall be applied with a pre-coated adhesive layer.

c.        Type A3 material, 0.020 inches thick, shall be applied with a pre-coated adhesive layer.

3.        Type B, Item 740.06, 0.015 inches thick, shall be used for Work Zone Pavement Markings.

a.        Type B, Type II material (non-removable).

4.        Type C, Item 740.06, 0.030 inches thick, shall be used for Work Zone Pavement Markings.

a.        Type C, Type I material (removable).

5.        Glass beads, none.

6.        Application of Preformed Pavement Marking, Item 645.

a.        Preformed Pavement Marking shall be applied according to the manufacturer’s recommendations packed with the material.

Documentation Requirements - 645 Preformed Pavement Marking

1.        General requirements per 645.

2.        Material as per 740.05, 740.06 and SS 1047 and SS 1089.

3.        Air and pavement temperature, type and condition of existing pavement.

a.        Temperature requirements are outlined in 645.03.

4.        Location and/or stationing of where work is performed.

5.        Measure in appropriate unit and turn in for pay.

6.        Use form CA-D-3A to document information.

646 Epoxy Pavement Marking

1.        Material Type, 740.07.

2.        Glass beads, 740.09 Type D.

3.        Application of Epoxy Pavement Marking, Item 646.

a.        Epoxy shall be applied at a surface temperature of 50 °F and above.

b.        Epoxy shall be applied in components, Part A and Part B, in proportions recommended by the manufacturer.

c.        Cleaning and surface preparation shall be done according to Item 646.04 for different pavement types and done according to manufacturer’s recommendations.

d.        Glass beads, 740.09 Type D, shall be applied at the rate of 31 pounds per 100 square feet.

                                                               i.      Glass beads shall be applied in a double-drop system with Size I, large gradation first and Size II, regular graduation second in equal amounts by weight in the same pass.

e.        Epoxy shall be applied at the rate of 22 gallons per mile of 4-inch (100 mm) line, 33 gallons per mile of 6-inch line and/or 1.25 gallons per 100 square feet.

Documentation Requirements - 646 Epoxy Pavement Marking

1.        General requirements per 646.

2.        Material as per 740.07 and 740.09, SS 1047 and SS 1089.

3.        Air and pavement temperature is above 50 °F.

4.        Location and/or stationing where work is performed.

5.        Measure in appropriate unit and turn in for pay.

6.        Use form CA-D-3A to document information.

647 Heat-Fused Preformed Thermoplastic Pavement Marking

1.        Material Type, Item 740.08.

a.        Type A90 is 90 mil thick.

b.        Type A125 is 125 mil thick.

c.        Type B90 is 90 mil thick.

d.        Type B125 is 125 mil thick.

2.        Glass beads, 740.09.

a.        Type A and B shall contain intermix beads throughout. Drop-on glass beads are not required unless using non-surface beaded markings.

3.        Application of Heat-Fused Preformed Thermoplastic Pavement Marking, Item 647.

a.        According to the manufacturer’s recommendations, Heat-Fused Preformed Thermoplastic Pavement Marking shall be applied only as auxiliary markings.

b.        If recommended by the manufacturer, apply primer sealer on Portland cement concrete pavement.

Documentation Requirements - 647 Heat Fused Preformed Plastic Pavement Marking

1.        General requirements per 647.

2.        Material as per 740.08, 740.09 and SS 1047 and SS 1089. State type of material used, A or B.

3.        Air and pavement temperature, type and condition of existing pavement.

a.        Temperature requirements are outlined in 647.04.

4.        Location and/or stationing of where work is performed.

5.        Measure in appropriate units and turn in for pay.

6.        Use form CA-D-3A to document information.

648 Spray Thermoplastic Pavement Marking

1.        Material Type, 740.10.

2.        Glass beads, 740.09 Type C.

3.        Application of Spray Thermoplastic, Item 648.   

a.        Spray Thermoplastic shall be applied to pavements less than a year old when the pavement surface and air temperature are 50 °F or higher.

                                                               i.      At the end of the construction season, if the surface temperature is 50 °F or less, apply Traffic Paint Type 1A.

b.        Spray Thermoplastic shall be applied to pavements one year or older when the pavement surface and air temperature are 70° F and rising.

c.        The Temperature of the Spray Thermoplastic, at the point of application, shall be at least 375 °F, but no more than 425 °F.

d.        Glass beads, 740.09 Type C, shall be applied at the rate of 10 pounds per 100 square feet.

e.        Spray Thermoplastic material shall be applied at a thickness of 45 mils.

f.         Spray Thermoplastic shall be applied at the rate of 762 to 886 pounds per mile of 4-inch line and 1,143 to 1,329 pounds per mile of 6-inch line.

Documentation Requirements - 648 Spray Thermoplastic Pavement Marking

1.        General requirements per 648.

2.        Material as per 740.10 and 740.09, SS 1047 and SS 1089.

3.        Air and pavement temperature, type and condition of existing pavement.

a.        Temperature requirements are outlined in 648.05.

4.        Location and/or stationing of where work is performed.

5.        Measure in appropriate unit and turn in for pay.

6.        Use form CA-D-3A to document information.

650 Roadsides

651 Topsoil Stockpiled

Because of the straightforward nature of this item of work, no detailed explanation of the item is required in this manual.

652 Placing Stockpiled Topsoil and 653 Topsoil Furnished and Placed

Documentation Requirements - 652 Placing Stockpiled Topsoil and 653 Topsoil Furnished and Placed

1.        Topsoil free of grass, brush, and roots.

2.        Opened up before seeding.

654 Renovating Existing Soil

Because of the straightforward nature of this item of work, no detailed explanation of the item is required in this manual.

656 Roadside Cleanup

Documentation Requirements - 656 Roadside Cleanup

1.        Clean up all debris outside excavated and fill areas and dispose of in accordance with 105.16 and 105.17.

2.        Prune trees 6 inches (15 cm) or less in accordance with item 666.

3.        Measure area for payment.

657 Riprap for Tree Protection

Documentation Requirements - 657 Riprap for Tree Protection

1.        Document material outlined in 657.02.

2.        Document tree wells in fill sections (657.02) and cut sections (657.04).

3.        Place hand laid riprap on 12:1 slope.

4.        Measure area for payment.

658 Tree Root Aeration

Documentation Requirements - 658 Tree Root Aeration

1.        Aggregate.

a.        Number 4 or 467 limestone as per 658.02.

2.        Placement of aggregate for trees not welled (658.04) and for trees that are welled (658.05).

3.        Measure volume for pay.

659 Seeding and Mulching

Documentation Requirements - 659 Seeding and Mulching

1.        Measure area to be seeded prior to start of operations and set-up test sections.

2.        Exclude area to be seeded at Contractor's expense.

3.        Incorporate fertilizer to a depth of 2 inches (5 cm) by _______________________ (harrowing, disking, etc.).  Type of fertilizer placed as outlined in 659.04.

4.        Calculate and document seed mixture required and used.

5.        Remove rocks and other foreign material larger than 3 inches (8 cm). Remove rocks and other foreign material 1 inch (2.5 cm) and larger in front of residences, commercial properties, and between curb and sidewalks.

6.        If broad cast seeding, rake and roll flat areas and track slopes with dozer.

7.        Mulch should be placed within 48 hours after seed has been sown.

8.        Identify areas to be paid by Contract Pay Item 659 separately from areas that are incidental to the work.

Note: Use form CA-EC-2 for field dimensions and calculations.

660 Sodding

Documentation Requirements - 660 Sodding

1.        Prepare area according to 659.

2.        Place sod on a prepared area and cover with a 1-inch (2.5 cm) minimum of straw.

3.        Pin sod on slopes of 2:1 and steeper if the strips are more than 6 feet (2 m) wide.

4.        Measure and pay per 660.10 and 660.11.

661 Planting Trees, Shrubs, and Vines

Description (661.01)

This item of work involves furnishing plantings (trees, shrubs, vines and other materials) and planting them according to the plan details, these specification requirements and applicable Standard Construction Drawings.

Labeling (661.05)

All plantings delivered to the project must have legible labels which indicate detailed information of the botanical genus and species name, the common name, the size, or age of each plant variety.  The labeling must state the quantity in the individual bundles, boxes, and bales.  These labels must be removed before the completion of the establishment period.

Acceptance (661.06)

General Appearance

The general appearance of a plant is the quickest way to judge its health and vigor. Be sure that the plant:

·         Is healthy, typical of their species or variety, and have a normal growth habit.

·         Meets the minimum dimensions given in the General Notes.

·         Container is not cracked or severely dented.

·         Container is weed free.

·         Is generally symmetrical with no large gaps in the branching structure.

·         Has no broken limbs.

·         Is free of excessive bark damage.

The foliage of the plant should be:

·         Erect and firm (except for weeping type plants). 

·         A uniform green color (except for fall color).

·         Vigorous, healthy, and robust.

·         Free of wilting, yellowing, and browning.

Note: Inspection of the plants before unloading from truck will save time and effort. Plants do not need to be individually inspected; a random inspection will be ok. The source of supply should be verified from the shipping ticket and compared to the plant material list (C&MS 661.03) as submitted earlier. Plants that do not meet specifications or differ in source of supply is justification for non-acceptance.

Problem Signs

Substantial amounts of brown or yellow foliage indicate the plant may be experiencing stress or shock. (Be aware that some trees, depending on whether they are deciduous or evergreen, may change color during the fall.)

Wilted foliage probably indicates a lack of water during shipping or storage. All plants must be completely covered during shipping (C&MS 661.04).  A thorough watering should restore the foliage to a healthy appearance within a couple of days. If not, the plant should be monitored for a few more days to see if it recovers before planting. If the condition does not improve, reject the plant. Broken and dead limbs indicate poor growing or handling conditions.

Testing for Dead Plants or Limbs

It is not always easy to tell if a plant is alive, particularly during the winter if the plant is a deciduous variety and has shed its leaves. Some of the techniques listed below will help to determine if a plant or a part of the plant is alive.

·         Using your fingernail, pocket knife, or other sharp object to scratch the bark on the trunk or limbs. A living plant will be light-green and moist just below the soft bark. If the bark is hard and the scar is brown, that part of the plant is dead. A random check of other areas will help to determine if the plant is vigorous and healthy.

·         Wrinkled bark that is off-color is an easy visual clue to dead parts of a plant.

·         Healthy limbs are flexible. They can be bent without breaking. Dead limbs are dry and brittle.

Container Grown Plants

The roots of a container grown plant should:

·         Be growing throughout the growing medium. 

·         Bind all the soil together.

·         Be white in color and moist; dark brown or blue black roots indicate damaged or dead roots.

Test for adequate root system: Inspecting the root systems of plants is very important.  It is not necessary to test all the plants; random checks will be sufficient if all the plants are from the same grower. If the plants are provided from more than one supplier or grower, be sure to random-check each group. Also, inspect any plants that appear different or out of character with a group of like plants.

·         For shrubs, hold the plant at the base of the trunk and gently lift the plant a few inches out of the container. If the entire contents of the container move and hold its shape in a firm mass of roots, the plant is properly "rooted-out" and ready for planting.

·         For trees, lay the container on its side. Hold the tree at the base of the trunk as close to the soil level as possible and gently slide the tree from the container a few inches. If soil is left in the container or if the root system is not growing throughout the entire container, the plant is not ready for planting and should be considered for rejection.

This method is not possible for large trees. Instead, dig 2 to 3 inches into the soil at the very edge of the container and look for a firm mass of small roots.

Root-Bound Container Plants

If plants have been growing in their container for a long time, the roots will wrap around the inside of the container. These roots need to be cut or sliced prior to planting. These cuts should be made along the sides and bottom. Cutting these circling roots will enable the plant to produce new root offshoots and grow without problems.

Checking Container Sizes

The size of large plastic containers may be indicated on the handle. Since these are nominal volume sizes only, there may be some variation in actual size, even though the containers from two different growers are labeled as being the same volume. Refer to Appendix for the minimum acceptable size ranges for containers without sizes printed on them or for wooden or metal containers.

Soil Condition in Containers

Check for the following soil conditions:

·         The soil level should be within a couple of inches of the top of the container. It should be a light (by weight) soil mix of mostly bark mulch and perlite or vermiculite (small white or silver particles that help hold water).

·         If you see clay, burlap, or wire in what is supposed to be a container grown plant, inspect closer to determine if the plant has been dug from the field and then placed in the container. The root development test described previously should determine this. A containerized plant in lieu of a container grown plant is not acceptable and must be rejected.

B&B Plants (Balled & Burlapped)

Inspect the rootball of B&B material for:

·         A firm, tight ball with no roots protruding outside the wrapping.

·         Wrapping that is snug and free of rips and holes.

·         Cracked balls or balls that are soft and look like a bean bag (these should be rejected).

·         Damage to the base of the trunk caused by wire or string used to secure the wrapping moist soil.

Soil Condition of the Rootball

The soil in a B&B rootball will almost always be clay or tight, sandy clay. This is necessary so that the soil will hold its shape during digging, as well as hold water during shipping and storage. Rootballs that are mostly sand may crack and break easily, possibly exposing roots to heat and dry air. Plants with a sand rootball should not be accepted. The rootball must be moist and shaded for protection at all times when shipping or storing.

Measuring Caliper

This is measured 6 inches above the ground (or top of rootball) up to and including 4-inch caliper size and 12 inches above the ground for larger sizes. Measurement should be taken with pincher type caliper or diameter tape.

Proper Habit of Growth

If a particular habit (e.g., single stem, multiple stem, etc.) has been specified, be sure to obtain plants that conform to this requirement. Height of branching should bear a relationship to the size and kind of tree, plus, the crown of the tree will be in good balance with the trunk as the tree grows. For example, 2-inch caliper = 12 to 14 feet average height; 16 feet maximum height.

Shade and flowering trees should have top growth symmetrically balanced. Shade trees should have a single leader. The branching should be well developed and characteristic of the species. For example, 3/4-inch caliper = 7 or more branches.

Multi-stem trees can be defined as clump or shrub form. Clump form is a tree which has two or more main stems arising from the root crown. Shrub form has multiple stems arising from the root crown in the manner of a shrub. Multi-stem trees are measured by height, taken from the ground level (or top of root ball) to the average uppermost point of growth of the plant.

Evergreen trees and shrubs should be full foliaged plants with uniform density. Sheared plants, such as pines sheared for Christmas trees, must be avoided unless specified. Most evergreen shrubs, such as juniper and yew, are measured by spread and should be the plant average. Evergreen trees like pines and spruces are measured by their height.

Deciduous shrubs should be well branched and full with no large holes from missing branches. Most are broad, upright type plants and are measured by their height.  Well grown material should have a height equal to, if not greater than, the spread. However, the spread should not be less than two-thirds of the height.

Rejected Plants

Plants rejected for the project should be removed as soon as possible. They should be marked to preclude the possibility of their installation on the job. Since discarded plants are the property of the Contractor, they should not be marked or mistreated in such a way as to make them unfit for other uses.

Insects

Do not allow the Contractors to deliver any plants to the site that are infested with harmful insects. Harmful insects are those that eat or bore into the plant including:

·         Caterpillars

·         Borers

·         Aphids

·         Scale

·         Mealy bugs

·         Bagworms

When inspecting for insects, look for:

·         The insects themselves. Most insects that suck plant juices usually do so from the undersides of leaves, particularly tender new leaves. Be sure to check these areas for aphids and mealy bugs.

·         Leaves that have holes or portions chewed out of their margin. Typically caused by caterpillars.

·         Small bag-like structures hanging from limbs. Typically an indication of bagworms.

·         Holes in the bark that looks like shotgun holes. Typically a result of borers.

·         Discolored bumps along a stem that look like shells. Typically an indication of scales.

Beneficial insects include lady bugs and butterflies. If insects are found, and it is unknown whether they are harmful or beneficial, the Inspector can call the local County Extension Office.

Table 661.A – Plant Damage - Trees and Shrubs

Things To Look For

What It Means

Action To Take

Minor amounts of breakage of small, twiggy growth.

Normal shipping damage. Should not be excessive.

Damaged twigs should be not be pruned.

Many small limbs broken.

Poor handling. Should not be excessive.

Broken limbs should be pruned. Reject if breakage is excessive.

Minor amounts of nicks and scratches.

Normal shipping damage. Should not be excessive.

None.

Gashes in trunk that are 1/8 (0.3 mm) deep or less and less than 1 inch (2.5cm) long.

Poor handling. Should not be excessive.

Treat with pruning paint. Reject if damage is excessive.

Gashes longer and deeper than the above.

Excessive damage. May stress plant and lead to loss of plant

Reject the plant.

Broken limbs 3/8 inch (l cm) in diameter or larger.

Poor handling. Damage done to larger limbs is more critical.

Broken limbs should be pruned. Reject if major limb or more than one.

Central leader (main trunk) is broken or cut.

Poor care or may have been pruned to meet specifications.

Reject the plant.

Limb partially

broken or cut and has to be

wrapped or repaired.

Someone tried to repair evidence of poor handling.

Reject the plant.

Inspection during Planting

The purpose of this part is to serve as a guide for an inspector who may not have the experience to determine that planting operations at the construction site are being properly completed in conformance with contract plans and specifications and good horticultural practices.

Planting stock should be inspected upon delivery. This will ensure that the plants delivered meet the requirements of the contract planting plans and specifications.

If plants are delivered before the site is ready for planting, a location should be chosen to store the plants until time to plant. This site should be away from construction traffic and protected from direct sun and wind. Asphalt or concrete areas are not acceptable as storage locations. Plant rootballs should be covered entirely with mulch, approximately 3 inches deep. Plants should be watered as necessary (see watering table) while in this temporary location.

Planting (661.10)

Unless in conflict with the contract specifications, the following check list of horticultural practices may be used by the Inspector. This information pertains to new or replacement nursery stock and not to large, mature plants.

1.        Plantings should be performed only during the specified planting season (see C&MS 661.07). Planting must be done between September 15 and June 1.

2.        The Inspector should check for proper positioning of the plants. After plants are set, burlap and any twine should be loosened, laid back, and cut away if bulky, without damaging the ball. Non-biodegradable materials should not be used in lieu of burlap.

3.        Check for correct depth of the plant crown. Depth of crown will vary for different soil conditions. See SCD LA-1.2 for details.

4.        Place approved backfill material around plant roots or plant balls. Be careful not to damage the ball or the fine root system. Backfill which is frozen or too wet is not acceptable.

5.        Eliminate air pockets in the backfill by filling, tamping, and watering as required by the specifications. It is best to water plants thoroughly before backfilling. Container plants should be moist at the time of planting.

6.        When the above operations have been completed, unless otherwise specified, place a berm of soil around the perimeter of the pit to form a basin or saucer to facilitate watering and retention of moisture.

7.        Mulch all plants to the specified depth with approved material (C&MS 661.11). The use of mulches prevents rapid temperature fluctuation, reduces moisture loss, and aids in weed control.

Note: Installation can directly affect a plants survival rate. Concentration on the installation process is critical to a project's success or failure. Because the nature of this work is based upon the end result (i.e., plants live or die), Inspectors need to watch the installation closely. If the Inspectors have any questions during the installation work, they should contact the Project Designer or other knowledgeable personnel as soon as possible.

Preliminary Preparation

1.        The Inspector and Contractor should jointly review and become familiar with all plan sheets, quantities, details, specifications, and other provisions of the Contract. At this time, questions or interpretations can be answered or problems resolved through discussion with the landscape architect, horticulturist, or other authorized persons.

2.        Sources of materials, other than plants required for planting operations, should be submitted for approval prior to use in the planting operation. Some of the materials that may require approval prior to use are topsoil, peat materials, (peats, mosses, humus, and related projected), compost, fertilizer, lime, mulch, stakes, wire and hose, and wrapping material.

3.        The Inspector or other approved personal should check and approve the stakeout of all planting areas and planting pit locations prior to excavation. Minor relocation of planting areas and pits can be done at this time to avoid utility lines, rocky outcrops, drainage ditches, existing plants, or impervious or wet soil conditions. If minor relocations of plantings are not possible, the Inspector should contact the Landscape Architect to adjust the design requirements.

Site Preparation

Prior to installing plant stock at the construction site, the following preparation must be completed according to the requirement of the contract plans and specifications.

1.        Excavation of planting pits, pockets, or beds to the required size and depth and spaced as shown on the plans.

2.        On-site preparation of backfill mixture, as called for by contract specifications. The backfill mix must consist of the following (C&MS 661.09):

a.        One part excavated soil.

b.        One part sphagnum peat moss, shredded pine bark, or EPA rated Class IV compost.

c.        One part sand.

d.        A slow release commercial fertilizer (0-20-20 or equal) added at a rate of 5 pounds per cubic yard (3kg/m) to the backfill mix.

Wrapping, and Bracing (661.12 and 661.13)

All plants should be pruned, wrapped, and braced as specified.

1.        Drive stakes solidly into the ground and guying installed to prevent movement of the plant until the root system is firmly established in the new planting location. See SCD LA-1.2 for details.

2.        Wrap trunks or stems of plants from the root crown to the lower limbs with approved material to protect against drying or other physical damage. Wrapping should not be done prior to planting deciduous trees.

3.        Plants should be pruned at planting time to restore a balance between the root and top growth. Tops should be pruned to compensate for the partial loss of roots when the plant was removed from the nursery. Tops should be pruned in a manner that will retain the characteristic shape of the plant.

4.        Broken or damaged branches must be removed. The central leader of a deciduous tree should never be trimmed or removed. Deciduous trees with competing leaders should not be accepted for the project.

5.        Prune all broken, torn, or damaged roots, leaving a clean cut surface to help prevent rot and disease.

6.        Prune deciduous shrubs if only branches are broken during installation. Coniferous evergreens normally should not be pruned, except for broken branches, unless otherwise specified or directed.

7.        Trees may be pruned before planting to save time and trouble. At this time, hand clippers can be used to cut closer than can be done with pole pruners (usually used for trees in an upright position). Pruning may be done under the Inspector's supervision prior to planting.

8.        The planting operation is complete by watering all plants as specified.

9.        See pruning diagram below.

Figure 661.A – Pruning Diagram

LANDSCAPE INSTALLATION INSPECTION CHECKLIST

Project No.:_____________________  Date: ___________

County: _________                  Route: _______ Section: _____________

Contractor: ____________________________________

Certified Landscape Technician: ____________________________________

Inspector: ____________________________________

Y

N

Item

Remarks

Plant Installation: General Condition

Plant identification (proper species, tag, certification)

Overall foliage, condition (shape, leaf color, wilt, scorch, etc.)

Leaf discoloration (spots, splotches)

Evidence of pruning (needed or properly performed)

Insects (chewing damage, presence of insects)

Condition of trunks and limbs (gashes, breakage)

Soil conditions in container or rootball (moist, dry)

Root system (rooted throughout, healthy white color)

Y

N

Size Specifications

Container size

Rootball size

Height

Spread

Caliper

Plant Delivery. Storage and Handling

All plants delivered on trucks are completely covered during transit

Rootballs and containers protected from direct sun

Handling and unloading from truck is done by the rootball or container and not by truck.

Are plants adequately watered

Plants are healed in until planted

Y

N

Plant Installation

Plant location staked in field

Plant spacings conform to plan notes

Plant pit or bed preparation conforms to details

Plant is properly placed in pit

Rootball relation to finished grade meets spec

Rootball supporting devices removed (twine, wire, etc.)

Backfill mix meets specifications

Backfill placed in lifts and properly watered

Fertilizers added if specified

Plant is properly watered during installation

Watering basin conforms to details

Tree supports installed according to details( stakes, guy wire)

Vegetation barriers installed according to details

Mulch installed according to details

Tree trunk is wrapped to first branch

Period of Establishment (661.14)

Warranty Periods 

Landscape projects normally include a period of establishment. During this time, all plantings on the projects shall be under the care of the Contractor. This period begins immediately upon completion of the planting operation for any plant or species group and continues until October 1, but no less than one growing season (i.e., June 1 to October 1).

The stress caused by improper handling may not show its effect immediately. Plants, particularly large trees, may be under stress for months before showing obvious signs. By then, it is difficult to relate the damage to the plant installation phase rather than the maintenance it has received. Again, this points out the need for care early in the installation to make sure that the quality of plants is the highest and the care they receive is the best.

During the establishment period, the Contractor must water, re-mulch, re-stake, and cultivate as necessary.  The Contractor is required to perform two weeding and mowing programs around trees, guy stakes, shrubs, and bed edges in order to remove all weeds and grasses from the planted and mulched areas.  The first program should begin around June 15 and the second approximately 8 weeks later.

Plant Establishment Period – Final Inspection

This inspection should be done on or about October 1 and include a plan-in-hand review of each planting area or bed to determine the arrangement, number, and species of plants called for on the planting plans are present. If all plants have been properly installed, there should be minimal settlement of the backfill. Proper mulch depth should be checked, as this will affect plant survival.

The Contractor must remove all stakes, guy wires, and wrapping material from plantings just prior to final inspection, except for any replacement plantings that have not been through their establishment period (C&MS 661.14).

Since this inspection is of major importance to the ultimate success if the project, the Contractor, Inspector, and Designer should be members of the inspection team.

All plants rejected during the inspection should be removed and replaced by new plants which meet all of the requirements of the project and specifications. The final acceptance of the project should not have been completed until all plant replacements have been satisfactorily made.

ESTABLISHMENT CHECKLIST - FINAL INSPECTION

Y

N

Item

Remarks

Foliage

Leaf wilt or browning

Leaves healthy and green

Yellowing

Spots of discoloration

Evidence of insect damage

Web or cocoons (caterpillars present)

Disease present

Remarks:

Tree trunk and limbs

Damage at the base of trunk

Broken limbs that need to be pruned

Dead limbs (no leaves present)

Damage from insects, birds, rodents, or animals

Sucker growth (prune out)

Straighten plant if needed

Misc.

Planting pit and rootball

Exposed roots (mulch is needed)

Settled backfill (replace as needed)

Animal damage

Moisture level of soil (water if needed)

All stakes, guy wires and wrapping removed

Weeds in mulch

Leaning trees (straighten if needed)

Plant replacement

Dead and missing plants replaced

Vandalism or vehicular damage

Ground cover and shrub bed area

Weeded

Dead shrubs (replace if needed)

Straighten if needed

Misc.

Remarks:

Plant Substitution List

Occasionally, landscape contractors may need to make recommended substitutions to the plant material list. This can occur if the plants are not available locally, there's not enough to meet the project requirements, or the specified size is no longer available. These substitutions should be pre-approved by the Designer before the Contractor purchases the plants.

Listed below is a chart to keep records on these substitutions.

Specified Plant

Substitution

Method of Measurement and Basis of Payment (661.17 and 661.18)

Measurement is done by counting the number of each species and size that was completed and accepted.

The Contractor is paid 40 percent of the bid price of each item when it is delivered to the project and is paid 40 percent after each item is planted.

At the end of the establishment period, after the final inspection, the Department will determine the actual number of living plants.  The Department will pay the remaining 20 percent of the bid price for all living plants at the end of the establishment period.

If for each pay item, less than or equal to 5 percent of the installed plants require replacement at the time of Project Completion, the Engineer may waive the establishment period for the replacement plantings, provided that the replacement plantings are installed in accordance with this specification and in the presence of the Engineer or Inspector.

If for each pay item, more than 5 percent of the installed plants require replacement at the time of Project Completion, the Contractor is required to install the replacement plantings in accordance with this specification.  The Department will pay the remaining percentage of the bid price at the time of Project Completion.  The replacement plantings are subject to the one year establishment period regardless of the Project Completion date.  After the replacement plantings complete the one year establishment period, the Department will inspect the replacement plantings and notify the Contractor of the Departments’ findings.  As final remedy under the contract, the Contractor is required to install replacement plants for all plantings that did not survive the establishment period at no additional cost to the State.

661 Appendix I – Shade Trees

Height relationship to caliper:

Caliper

(inches)

Avg. Height

Range (feet)

Maximum

Height

(feet)

Minimum

Diameter

Ball

(inches)

3/4

6 to 8

10

14

1

8 to 10

11

16

1-1/4

8 to 10

12

18

1-1/2

10 to 12

14

22

1-3/4

10 to 12

16

24

2

12 to 14

16

24

2-1/2

12 to 14

16

28

3

14 to 16

18

32

3-1/2

14 to 16

18

38

4

16 to 18

22

42

5

18 and up

26

54

Tree caliper is measured 6 inches above ground level, up to and including 4 inch caliper size, and 12 inches above the ground for larger sizes.

Container Specifications – Shade Trees

Tree sizes and acceptable container sizes:

Height

Container Size

12 in.

18 in.

2 ft.

3 ft.

#1

2 ft.

3 ft.

4 ft.

#2

4 ft.

5 ft.

6 ft.

#3

All container grown plants shall be healthy, vigorous, well rooted, and established in the container in which they are sold.

An established, container-grown tree is a tree which is transplanted into a container and grown sufficiently long for new fibrous roots to have developed, so the root mass will retain its shape and hold together when removed from the container.

661 Appendix II - Deciduous Shrubs

Height

Minimum Diameter

Ball (inches)

12 in.

8 in.

18 in.

9 in.

2 ft.

10 in.

3 ft.

12 in.

4 ft.

14 in.

5 ft.

16 in.

6 ft.

18 in.

7 ft.

20 in.

8 ft.

22 in.

9 ft.

24 in.

10 ft.

26 in.

Plants dug to the specifications in the above table should have the center of the stem or cluster of stems of the plant in the center of the ball.

661 Appendix III - Coniferous Evergreens

Broad spreading and Globe Types (eg., Taxus media)

Height

Minimum Spread

Minimum Diameter Ball

6 in.

6 in.

9 in.

9 in.

8 in.

12 in.

l0 in.

8 in.

15 in.

12 in.

10 in.

18 in.

15 in.

10 in.

2 ft.

18 in.

12 in.

2-1/2 ft.

21 in.

14 in.

3 ft.

24 in.

16 in.

3-1/2ft.

18 in.

4 ft.

21 in.

5 ft.

24 in.

Container Grown Specifications

Height      I

Container Size

6in.

9in.

12 in.

#1

12in.

15in.

#2

18in.

2 ft.

2-1/2 ft.

#3

Conicals, Broad Upright, and Columnar (e.g., Pinus, Picea, and Thuja)

Height

Spread

Minimum

Diameter Ball

12 in.

8 to 12 in.

10 in.

15 in.

9 to 15 in.

10 in.

18 in.

12 to 18 in.

10 in.

2 ft.

15 to21 in.

12 in.

2-1/2 ft.

18 to 24 in.

12 in.

3 ft.

21 to 30 in.

14 in.

4 ft.

2-1/2 to 3 ft.

16 in.

5 ft.

3 to 4 ft.

20 in.

6 ft.

22 in.

7 ft.

24 in.

8 ft.

27 in.

10ft.

34 in.

12 ft.

34 in.

Ball sizes should always be of a diameter and depth to encompass enough of the fibrous and feeding root system as necessary for the full recovery of the plant.

Plants dug to the specifications in the above table should have the center of the stem or cluster of stems of the plant in the center of the ball.

Container Grown Specifications

Height

Container Size

6 in.

9 in.

12 in.

15 in.

18 in.

#1

12 in.

15 in.

18 in.

2 ft.

#2

18 in.

2 ft.

2-1/2 ft.

3 ft.

3-1/2 ft.

#3

661 Appendix IV - Broadleaf Evergreens

Spreading and Dwarf Types (e.g., Buxus and Cotoneaster)

Spread

Minimum Diameter

Ball (inches)

18 in.

10 in.

2 ft.

12 in.

2-1/2 ft.

14 in.

3 ft.

16 in.

3-1/2 ft.

18 in.

4 ft.

21 in.

Container Grown Specifications

Height

Container Size

6 in.

9 in.

12 in.

#1

12 in.

15 in.

#2

18 in.

2 ft.

2-1/2 ft.

#3

All container grown plants shall be healthy, vigorous, well rooted, and established in the container in which they are sold. They shall have quality tops and be in a healthy growing condition.

Cone and Broad Upright Types (e.g., Rhodoendron)

Height

Minimum Diameter

Ball (inches)

18 in.

10 in.

2 ft.

12 in.

3 ft.

14 in.

4 ft.

16 in.

5 ft.

20 in.

6 ft.

22 in.

Container Grown Specifications

Height

Container Size

6 in.

9 in.

12 in.

15 in.

18 in.

#1

12 in.

15 in.

18 in.

2 ft.

#2

18 in

2 ft.

2-1/2 ft.

3 ft.

3-1/2 ft.

#3

662 Landscape Watering

General

When watering by hand, attention should be given to the type of device used to apply the water. If the water is applied at too high a rate, the force of the water will displace mulches, soil, and expose roots. All equipment used to direct water into the watering basin should have a flow-control device that will break the impact of the water, so it will flow gently into the basin.

Water should not be applied where runoff will occur. If the plant is newly planted, too much water can erode the watering basin and allow water to escape before it can soak down into the soil. If this occurs, the basin should be repaired before the next watering.

WATERING TABLE (662.03-1)

Shrubs

12 to 36 inches (300 to 900 mm), height

4 gallons (15 L)

Shrubs

36 inches to 5 feet (900 mm to 1-1/2 m), height

7 gallons (25 L)

Trees

5 to 8 feet (1-1/2 to 2.5 m), height

15 gallons (55 L)

Trees

2 to 3 inches (50 to 75 mm), caliper

25  gallons (95 L))

Trees

3 to 4 inches (75 to 100 mm), caliper

30 gallons (115L)

Trees

Greater than 4 inches (100 mm), caliper

35 gallons (115 L)

WATER-RELATED STRESS SYMPTOMS

Symptoms

Soil Condition

Problem

Action to be Taken

Leaves are slightly dropping. Soft, hazy-green color.

Dry

Lack of water

Apply water as soon as possible.

Leaves are dropped and wrinkled.

Dry

Severe lack of water

Apply water immediately

Leaves are dropping, brown and falling from the plant.

Very dry, look for cracking.

Severe lack of water

Water immediately.  Plant is near to shedding its leaves to compensate for lack of water.

Leaves are brown along margins but not drooping.  Some leaves are falling from the tree.

Wet

Over-watering

Stop watering.  Allow soil to dry

Documentation Requirements - 662 Landscape Watering

1.        Document watering method.

2.        Determine gallons of water used for payment (weigh slips or measure tank).

666 Pruning Existing Trees

Documentation Requirements - 666 Pruning Existing Trees

1.        Pruning and payment method outlined in item 666.03 thru 666.08.

670 Erosion Protection

Documentation Requirements - 670 Erosion Protection

1.        Document and measure the erosion control items installed and maintained in accordance with the plans. Use form CA-EC-1.

671 Erosion Control Mats

Documentation Requirements - 671 Erosion Control Mats

1.        Document type of erosion control mats (Type A thru Type I 670.03), seeding, and mulching installed and maintained.  Materials outlined in 671.02.

2.        Measure areas for payment.

SS 832 Temporary Sediment and Erosion Controls

Description (832.01)

All references to 207 have been removed from the C&MS 2013.  This Sediment and Erosion Control contract item will remain as a supplemental specification to allow for the timely contract revision of the NPDES construction general permit, commonly referred to as the storm water permit. Projects which involve 1 acre or more of earth disturbing activity are required to have an NPDES Permit.  This permit pertains to both the work within the project work limits and related support activities. Supplemental Section 832 is required to be installed in all contract documents regardless of the amount of Earth Disturbed Area (EDA).

1.        The Contractor is required to furnish a fully executed Co-Permittee form.

2.        The Contractor is required to furnish a site specific Storm Water Pollution Prevention Plan (SWPPP) that is compliant with the NPDES Permit (see SS832 Appendix E).

3.        The Contractor is required to locate, furnish, and maintain all BMP as identified in the Contractor’s SWPPP.

4.        Project personnel are required to read the permit, SS832 Appendix E, and should inform the Contractor of any non-compliant permit conditions known on the construction site.

5.        If stream or river crossing (causeway) provisions are not specifically included in the contract documents, the Contractor must obtain the proper permit to construct a stream or river crossing.  Fording streams, rivers, or waterways is not permitted.

Definitions (832.02)

Co-Permittee:  The Contractor is required to file the Co-Permittee form to OEPA.  This form notifies OEPA that the Contractor is an “Operator.” Both ODOT and the Contractor are identified as “Operators” in the NPDES Permit.  As a result, both ODOT and the Contractor are required to keep the construction activity in compliance with the NPDES Permit.  ODOT contractually holds the Contractor responsible for compliance and provides compensation for the Contractor’s efforts.  ODOT cannot knowingly allow a permit violation to exist without taking corrective measures.  If a permit violation or deficiency is identified, the Contractor should be notified and reminded of his contractual responsibility to maintain permit compliance. 

Standard Construction Drawing Reference (832.03)

The Standard Construction Drawings (SCD) provide detailed information which describe the materials, construction, and installation requirements for most of the BMP.  The SCDs are referenced in SS 832; however, they are often overlooked by the Contractor’s crews who perform the work.  The SCDs should be brought to the Contractor’s attention as early in the project as possible, and preferably at, or even before, the preconstruction meeting.  Project staff should use the SCDs when inspecting and measuring BMP for payment.

Requirements (832.04)

Post construction NPDES Storm Water Management Requirements are not included in this specification.  Post construction controls are not considered temporary, and therefore, are addressed in the project plans.  Project staff should be familiar with the Post Construction BMPs, where they are located in the plans and on-site. OEPA may specifically inspect these BMP during a field visit.

Provisions (832.05)

The “Provisions” portion of the specification identifies how the ODOT contract handles storm-water enforcement actions resulting from non-compliance.  The NPDES Permit holds the Operator responsible for compliance.  Both ODOT and the Contractor are identified as Operators.  If a non-compliant condition results in OEPA enforcement action, the Contractor agrees to:

1.        Make all necessary corrections resulting from an incomplete or inadequate SWPPP.

2.        Reimburse ODOT for any fine penalty assessment damage judgment or expense resulting from non-compliance regulatory action.

3.        Indemnify and hold the Department harmless for any fine penalty assessment damage judgment or expense resulting from non-compliance regulatory action.

4.        If a stop work order is issued resulting from an incomplete or inadequate SWPPP and/or BMPs, the Department will find the Contractor in default.

5.        Failure to correct non-compliant site conditions may result in suspension of the work and/or removal of the project superintendent.

When notifying the Contractor of non-compliance matters, the provisions portion of the spec should be referenced.

EDA Requirements (832.06)

ODOT Maintenance projects involving less than 5 acres of maintenance work activity are exempt from the NPDES Permitting requirements.  For a project to be eligible for this exemption, it is required that all work activity included in the project fall under the OEPA approved list of “Maintenance Activities.” The approved list can be found at:

                http://www.epa.ohio.gov/dsw/storm/routine_maint.aspx

If the Contractor elects to work outside of the project limits (typically areas for borrow, waste, staging, or storage) and the EDA is greater than 1 acre, the Contractor is required to either include the areas outside the project limits on the SWPPP or obtain a separate, Contractor-held NPDES Construction General permit.

Work Outside the Project Work Limits

If the project has identified any EDA within the project limits, even less than a 1 acre Project EDA, ODOT will compensate the Contractor for the installation of appropriate BMP within the project limits.  For projects with more than 1 acre of EDA, the Contractor is required to specifically identify all work areas located outside of the project work limits on his SWPPP.  The cost for expanding the SWPPP coverage outside of the project work limits is included in the lump sum price bid for SWPPP.  See 107.19 for general environmental protection requirements.  It is important to note that the Contractor EDA may be on ODOT R/W but outside of the project work limits.

Jurisdictional Waters may include Waters of the State or Waters of the U.S.  In either case, a permit may be required (107.19). Placement of fill in these regulated waters (streams, ponds, lakes, waterways, etc.) without a permit is illegal.  The Contractor is required to furnish the proper permit for any area affected by his operation that is outside of the project work limits.  This may include temporary work pads, stream crossings, causeways, or placement of any fill in Jurisdictional Waters that are not otherwise identified in the plans.

The Contractor is required to furnish spill response equipment for all operations working next to a body of water. See 107.19 and Special Provisions.

The Contractor is required to furnish water handling controls that are capable of preventing sediment-laden water from being discharged from the site.  This is an important consideration when working in and around water areas on drilled shafts, cofferdams, dewatering operations, etc. (107.19).

The Contractor is required to provide a location to properly wash out cement or concrete trucks. Concrete washdown water is toxic and can cause a fish kill or other serious environmental impact.  Concrete truck washdown BMP must be located away from all bodies of water.  The Contractor is required to locate the concrete washout BMP(s) on the SWPPP.

BMP Materials (832.07)

The Standard Construction Drawings referenced on the plan title sheet contain details that are often overlooked by the Contractor.   The SCDs have been revised to address the latest version of the storm water permit.  Earlier SCD versions may reference sediment and erosion controls that are no longer recognized by OEPA as viable BMPs.

Furnish the materials as outlined below:

1.        Furnish commercial fertilizer, seed, and mulch material that meet 659.

2.        Furnish filter fabric material for ditch checks that meets standard drawing DM-4.4.  It is important to note that this BMP includes the installation of an aggregate component to prevent high flows and sediment accumulation from collapsing the fabric fence.

3.        Furnish rock material for ditch checks that meets standard drawing DM-4.4.

4.        Furnish filter fabric material for inlet protection that meets standard drawing DM-4.4.

5.        Furnish filter fabric material for perimeter controls that meets standard drawing DM-4.4.

6.        Furnish filter fabric material or hay or straw bale material for bale filter dikes that meets standard drawing DM-4.3.

7.        Furnish excavation and embankment material for sediment basins and dams that meets the capacity and 48-hour draw down requirements described in the NPDES permit.

8.        Furnish pipe material for slope drains that meets standard drawing DM-4.3.

9.        Furnish rock channel protection material that meets standard drawing DM-4.3.

Furnish and Locate BMP (832.08)

The NPDES permit requires that the SWPPP identify the type, location, and size of all sediment and erosion controls installed or proposed on the project site.  The Contractor is required to keep the SWPPP current with the controls installed and maintained on site SS832 Appendix E Part III.C.2.D.

Figure 832.A – Sediment Settling Pond with Construction Fence and Stream Perimeter Filter Fabric Fence

Figure 832.A2 – Perimeter Filter Fabric Fence

Perimeter Controls (SS 832.08.A)

Apply perimeter control practices to protect the disturbed area from off-site runoff and to prevent sediment from discharging off-site to areas below the construction site. Sediment and runoff barriers surrounding the area disturbed by construction activity prevents runoff from moving off-site and impacting surface waters downstream.

1.        Perimeter controls must be placed and identified in the SWPPP before or concurrent with any clearing and grubbing operation.

2.        The perimeter controls should be dated on the SWPPP along with the dates of the clearing and grubbing.

3.        Perimeter controls BMP are detailed in standard drawing DM-4.4.

4.        Perimeter controls (typically dikes) can effectively divert water away from the project, and when designed properly, can separate watersheds into smaller drainage areas reducing the need for large sediment settling ponds.

5.        Perimeter controls should be used to protect all water bodies (ponds, streams, wetlands, etc.) and any areas shown on the plan which may be adversely affected by construction surface drainage.

Figure 832.A3 – Perimeter Control, Water Body Protection

Filter Fabric Fence

Filter Fabric Fence is used to control sheet flow, not concentrated flow.  The application of Filter Fabric Fence is limited by the steepness of the slope and the size of the surface area draining toward the fence.  The regulatory limitations for Filter Fabric Fence are outlined in the NPDES Permit. See SS832 Appendix E, Part III.G.2.d.

It is critical that Filter Fabric Fence be installed in accordance with standard construction drawing DM 4.4.  The fabric must be installed in a 6-inch by 6-inch trench and backfilled with compacted earth.  Placement of the fence along the ground surface and shoveling fill on top of the lower edge of the fabric is not acceptable.

Filter Fabric Fence is a filter.  It should be installed down gradient of EDA to filter sediment from sheet flow.  Do not install silt fence above EDA areas.

When Filter Fabric Fence fails in the field, it is typically caused by one or more of the following:

1.        Improper burial depth.

2.        Drainage area exceeds the capacity of the fence.

3.        Fence is not parallel to the surface contours.

4.        Poor maintenance.

Dikes

Dikes can be used as a perimeter control.  Dikes function best by collecting and concentrating sheet flow then directing it to an appropriate controlled outlet or other BMP which does not allow the discharge of sediment.

Inlet Protection (SS 832.08.B)

Place Inlet Protection as outlined below.  The location and date of placement, maintenance, or removal should be identified on the SWPPP.  It is recommended that all Inlet Protection be numbered and dated both in the field and on the SWPPP.

Figure 832.B – Inlet Protection

1.        If Inlet Protection is being used as a BMP, it is required that they be located on the SWPPP.

2.        Inlet Protection should be dated on the SWPPP.

3.        Inlet Protection should be used around Catch Basin inlets and/or any structure that conveys storm water.

4.        Inlet Protection requirements are detailed on standard drawing DM-4.4.

5.        When Inlet Protection fails in the field, it is typically caused by one or more of the following:

a.        Improper burial depth.

b.        Inadequate height of fence above inlet invert.

c.        Improper lap of fabric.

d.        Poor maintenance.

Construction Seeding and Mulching (SS 832.08.C)

Seed and mulch all disturbed areas that have been idled, particularly before winter shut down.

Figure 832.C – Construction Seeding and Mulching

Figure 832.C2 – Winter Seed and Mulch, with mulch crimped in place

1.        The rate furnished for straw mulch is 3 tons per acre (0.5 metric ton/1000 m²).

2.        The rate furnished for fertilizer is half the rate found in Item 659.

3.        Do not place Construction Seed on frozen ground.

4.        Install Construction Seed and Mulch on disturbed areas that work will be suspended during the winter.  Standard Construction Seed and Mulch should not be installed between October 15 and March 15.

5.        Winter Seed and Mulch is the standard erosion control practice for EDA occurring between October 15 and March 15.  This BMP includes mulch crimped in place or a Bonded Fiber Matrix capable of providing sufficient protective cover to comply with the NPDES permit.  The cost for installing BFM mulch is typically greater than crimped mulch.  The BFM mulch is better suited for limited area applications on steep slopes or areas where crimping implement access is limited.  The use of other seed and/or mulch materials in this time period requires Department approval.

6.        Temporary cover such as Construction Seed and Mulch, Construction Mulch or Winter Seed and Mulch should be installed as the construction progresses and not when a big enough area is exposed to the elements.  Temporary cover requirements address the allowable time that disturbed earth may remain exposed.  It is important that temporary cover installation keeps up with construction progress.

7.        The date of construction seed placement should be recorded on the SWPPP and corresponding NPDES inspection reports.

Slope Protection (SS 832.08.E)

Fill slopes that are greater than 8 feet (2.5M) and have had no filling activity for 3 weeks.

Figure 832.E – EC Items Required For Slope Protection

1.        If dikes are being used as a BMP, it is required that they be located on the SWPPP.

2.        Dikes should be dated on the SWPPP along with the date of the slope construction.

3.        Dike and slope drain construction requirements are outlined on standard drawing DM-4.3.

Figure 832.E2 – Item 670 Recommended for Cut Slope construction

When constructing cut slopes, a surface water control ditch should be installed before the slope excavation begins.

1.        The ditch should be constructed at the top of the cut slope.

2.        If the ditch is being used as a BMP, it is required that it be located on the SWPPP.

3.        It is important that the ditch is constructed with sufficient grade to prevent water from saturating the underlying soils and causing slope instability problems.

Ditch Checks and Ditch Protection (SS 832.08.F)

Figure 832.F1 – Filter Fabric Ditch Check

1.        Construct Filter Fabric Ditch Checks as soon as ditch is cut.

2.        Ditch Checks shall be placed per the SWPPP or as required.

3.        Ditch Checks are BMP and are required to be recorded on the SWPPP along with the ditch construction.

4.        Filter Fabric Ditch Checks construction requirements are detailed on the standard drawing DM-4.4.

5.        Filter Fabric Ditch Checks are limited to drainage areas of 2 acres (0.8 ha) or less.

6.        Filter Fabric Ditch Checks include No. 1 thru No. 4 aggregate components.  The Engineer may waive the aggregate requirement when ditch checks are needed in the clear zone.  The aggregate should be replaced with straw bales staked in place against the filter fabric as detailed on standard construction drawing DM-4.4 (see Figure 832 F2).

7.        It is important that Ditch Checks be in place by the end of the day if working on the ditch.

Figure 832.F2 – Filter Fabric Ditch Check with Straw Bale Backing

Figure 832.F3 – Rock Ditch Check

1.        Rock Ditch Checks shall be placed per the SWPPP or as required. 

2.        If Rock Ditch Checks are used as BMP, they should be recorded on the SWPPP.

3.        Rock Ditch Checks should be installed as soon as the ditch is cut.

4.        Rock Ditch Checks construction requirements are detailed on the standard drawing DM-4.4.

5.        Rock Ditch Checks are limited to drainage areas between 2 and 5 acres (0.8 and 2.0 ha).

6.        It is important that Ditch Checks be replaced by the end of the day if working on the ditch.

Bale Filter Dike (SS 832.08.G)

OEPA no longer recognizes Bale Filter Dikes or Bale Ditch Checks as acceptable BMPs. 

Filter Fabric Ditch Checks that are installed in the clear zone may use straw bales in lieu of the aggregate backing (see DM 4.4).  Installation of straw bales is permitted only when allowed by the Engineer.

Sediment Basins and Dams (SS 832.08.H)

Place Sediment Basins and Dams as outlined below and as required by the NPDES Permit. 

Figure 832.H – Sediment Settling Pond

1.        Sediment basins and dams are required to be placed within 7 days after completion of grubbing and constructed before grading begins.

2.        Sediment basins and dams should be installed as per the SWPPP and as required by the NPDES Permit.

3.        Sediment basins are a BMP and are required to be recorded on the SWPPP and routinely inspected. 

4.        Concentrated flow discharging from areas containing EDA is required to pass through a Sediment Settling Pond.

5.        Typical field locations include the bottom of a ravine, culvert inlets and outlets, at the end of a ditch, and any concentrated water exit point.

6.        Sediment Settling Ponds, Basins or Dams should never be constructed in a body of water.

7.        Sediment Basins and Dams should be sized to retain 67 cubic yards (125 cubic meters) of water for every acre of drainage area.  The latest version of the OEPA NPDES General Construction Permit requires that the basin volume described above be designed to have a minimum 48 hour draw down time.  Sediment storage ponds are required to include an additional volume specifically designed for sediment storage.  The sediment storage portion of the pond consists of 34 cubic yards per acre of disturbed earth in the watershed.  The SWPPP designer is required to attach the computations for sediment settling pond design to the Acceptance submittal (832.10).

8.        Construction requirements for Sediment Basins and Dams are detailed on the standard drawing DM-4.3.

9.        Install construction fence as needed for safety considerations.

River, Stream, and Water Body Protection (SS 832.08.I)

All rivers, streams, and water bodies must be protected from all sediment-laden or turbid water.

Figure 832.I – Stream Protection

Stream Relocation (SS 832.08.J)

Fully stabilize any temporary-relocated waterway before the water is diverted, as outlined below.  Examples are temporary run-arounds to constructed culverts, temporary ditches, or any temporary waterway constructed by the Contractor to build the project.  General and/or specific permits may be attached to part of the special provisions shown in the plan.  Some individual or specific permits may include requirements in addition to what is required under the general NPDES Permit.

Figure 832.J – Temporary Channel

Temporary Channel

1.        Temporary channels require stabilization with rock channel protection (Item 670 Erosion Protection) or a stand of grass at least 70 percent established.

2.        Temporary channels are required to be stabilized before any flow is diverted into the channel.

3.        If the Temporary channel is a 404/401 permit requirement, costs associated with constructing, maintaining, and removing the temporary channel are incidental to the work taking place within the footprint of the 404/401 permit area.

Causeways and Access Fills (Stream and River Crossings and Fills) (SS 832.09)

Equipment can cross a waterway only by means of a permitted crossing or causeway.  Regulatory permits are required prior to any disturbance to the waterway.  Place Stream or River Crossings (Causeways) as outlined below and date the placement on the SWPPP. 

Figure 832.K – Stream Crossing

1.        Ensure the causeway is a height of 1 foot (.3m) above the Ordinary High Water Mark (not necessarily the “normal water elevation”).

2.        The causeway should be as narrow as practical to provide for passage of the equipment while preventing the movement of any fill into the water.

3.        Furnish culvert pipes if filling more than one-third of the waterway.  Pipes may be specifically required per the terms of the 404/401 permit.

4.        Only clean, dump rock (non-erodible fill) is permitted for use in the waterway.  Broken concrete can be used as a temporary fill if all exposed rebar has been removed.

5.        Furnish 50 feet (15m) approach drive of dump rock (non-erodible fill) on both sides of the causeway.

6.        When a high water event impairs the Contractor’s ability to work and causes a delay, the Department will allow an excusable, non-compensable delay.  The Department will compensate the Contractor for required repairs to the causeway and access fills that were damaged as a result of the high water event.

Causeways and Access Fills Construction and Payment (SS 832.10)

Typically, Causeways and Access Fill environmental protection costs are incidental to the work contained within the 404/401 permit boundary.  In some cases, Causeways and Access Fills are paid as a separate item.  It is important to note that all environmental controls within the 404/401 permit boundary are incidental to the work conducted within that boundary.  The Sediment and Erosion Control Prices (SS 832 Appendix F) should not be used as compensation when BMP are installed within the 404/401 permit boundary.

Figure 832.L – Required Maintenance

Maintenance (SS 832.11)

1.        The Contractor is required to maintain all BMP throughout its functional life on the project.

2.        All BMP are required to be sized and designed to withstand a minimum 1/2-inch rainfall event.

3.        The cost for maintaining BMP is included in the price paid per unit of BMP.  Compensation is provided for BMP replacement and/or repair required as a result of a rainfall event greater than 1/2 inch.  The Contractor is required to inspect, record, and report all impacts to the BMP that require maintenance and/or replacement.  BMP must be inspected weekly and within 24 hours of a 1/2-inch or greater rainfall event.

4.        Sediment that accumulates at the BMP requires removal and proper disposal as part of the Contractor’s responsibility for maintenance.  Safeguards must be in place to prevent the release of sediment into waters of the state during the BMP maintenance effort.  Disposal of accumulated sediment must be compliant with C&MS 107.19.

5.        Routine maintenance and repair of BMP is required to be conducted within 3 days of the inspection which identified the need.  Sediment settling ponds must be repaired and/or maintained within 10 days of the inspection.  If deficiencies or violations have been identified on-site, the Contractor is required to correct and mitigate the conditions within 48 hours of notification by the Department or regulatory agency SS832.05.G.

6.        BMP should not be removed until the Earth Disturbing Activity has been completed and, “A uniform perennial vegetative cover with a density of at least 70 percent has been established,” on all unpaved areas.  If a silt fence is removed to accommodate the final grading and seeding operation, it should be replaced after the seeding work is completed or other perimeter control BMP should be installed to provide appropriate protection.  OEPA recommends the installation of sediment basins down gradient as an appropriate control measure when perimeter controls are removed for final grading and seeding.

BMP Maintenance Requirements

Routine maintenance on BMP is required when repairs are needed and when:

1.        Rock Ditch Checks have sediment covering half the height of the rock.

2.        Perimeter Filter Fabric Fence, Filter Fabric Ditch Checks, and/or Inlet Protection have sediment covering half the height of the fabric.

3.        Sediment Settling Ponds require sediment remove maintenance when the required sediment settling zone is full.

4.        Bale Filter Dikes have sediment covering half the height of the bale.

5.        Erosion Control Mats require replacement when they are torn and/or displaced.

6.        Construction Seeding and Mulching has been displaced and re-application is needed.

Permanent stabilization must be achieved before the project is accepted.  Once the project is permanently stabilized, (see SS832 Appendix G, Part VII.H) all temporary BMP must be removed and resulting debris disposed of appropriately.

Storm Water Pollution Prevention Plan (SS 832.12)

1.        The Department requires that the SWPPP be designed by an Engineer (P.E.) that is also a Certified Professional in Erosion and Sediment Control (CPESC) Registration of certified professionals can be found at the following websites:

https://license.ohio.gov/lookup/default.asp

http://www.cpesc.org/cc-info/us-directory.asp 

2.        The SWPPP must show the location of the BMP for all areas with EDA related to the project.  This includes borrow, waste, staging, and storage areas that experience EDA.

3.        It is important that the SWPPP identify the watersheds and the area disturbed by the construction in each watershed (SS 832.12 G).  This provides the project and Contractor with the location of all drainage outlets from the project.  This information is helpful in conducting appropriate inspections (see SS 832.14 below).

4.        If the Contractor is proposing BMP other than those identified on the standard BMP pricing schedule, the SWPPP needs to describe the proposed BMP for the Engineer’s approval, particularly if compensation is a consideration.

SWPPP Acceptance (SS 832.13)

The intent of acceptance is to determine if the SWPPP developed by the Contractor is a reasonable reflection of the site conditions and identifies reasonable controls that will uphold compliance with the NPDES Permit.  Acceptance is not regulatory approval.  If the SWPPP is accepted, the Department is recognizing that the Contractor has developed what appears to be an appropriate plan to comply with NPDES.  Sections A through G of Part III in the NPDES Permit is a checklist that identifies the minimum SWPPP elements that the Contractor must have on his plan.  If the SWPPP is not accepted by the project, and the Contractor requests assistance from the project to develop an acceptable SWPPP, guidelines are available in the form of a checklist from OEPA.  The checklist is titled, “SWPPP Checklist for Construction Activities,” and can be found at:

http://www.epa.ohio.gov/dsw/storm/const_SWP3_check.aspx

 Project staff can, and should, make recommendations to the Contractor to facilitate permit compliance.  It is important to note that the Contractor’s responsibility and liability related to NPDES compliance is reduced when he is directed to perform compliance work by the Department.  The Contractor is required to tailor his operation in order to comply with the NPDES Permit.  The purpose of this submittal is to demonstrate compliance with the contract documents.  If the Contractor intends on using the submittal as a mechanism to alter the contract requirements, he is required to “prominently call attention to the proposed deviation from the contract in the submittal.” 

Inspections and Updates (SS 832.14)

Inspections are a requirement of the SWPPP.  The NPDES Permit requires that all controls (BMPs) and all surface water outfalls on the site are inspected at least once every 7 calendar days and within 24 hours of any storm event greater than 1/2 inch as per SS832 Appendix E part III.G.2.i.  The Storm Water Inspection Report is a document of record that carries legal liability.  The Contractor has the contractual responsibility to conduct the inspections by or directly under the supervision of the SWPPP designer who sealed the SWPPP.  At least once a month, the SWPPP designer is required to sign off on the inspection report with the following standard certification language:

"I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations."

 SS832 Appendix E part III.G.2.i describes the minimum components of an inspection report. 

It is important that the inspection specifically includes all discharge locations.  If erosion is occurring or sediment is accumulating at a discharge location along the boundary of the project, immediate action needs to be taken to document and correct the problem.  For situations where off-site sediment is mixing with surface water from the project, care should be taken to separate the flows and divert the off-site water away from the site (when possible).  In many instances, the separation and diversion of off-site surface water is not possible.  In these cases, the Contractor should monitor the in-coming surface water and document the conditions as part of the routine inspection effort.  In the event that OEPA or others identify an NPDES Permit violation, the remedy and/or corrective action can be identified and implemented quickly and additional enforcement actions can often time be avoided.

OEPA refers to the SWPPP as a “living, breathing document.”  The intent of the SWPPP requirement of the permit is to plan the work in advance and incorporate the BMP in such a way that prevents the discharge of pollutants to waters of the state.  The permit requires that the SWPPP be kept current with the site conditions and document the addition, removal, and maintenance of the BMP on the SWPPP (see SS832 Appendix E, part III.D).  The Department requires that the Contractor perform the required inspections.  The Inspector must be CPESC trained.  When modifications to the SWPPP are needed, the Inspector is required to get approval from the SWPPP Design Engineer.  The SWPPP Design Engineer’s approval is documented as part of the routine inspection report, which is provided to the project at least once a month. The Contractor’s Erosion Control Inspector is required to provide the project with a weekly certification that the site is compliant with the permit.  If the project does not receive the weekly certifications, SS 832.05 should be enforced, and the Contractor should be notified in writing.  The certification requirement provides the project with the ability to track compliance issues and to stay current with the required documentation. 

Documentation Requirements – SS 832 Temporary Sediment and Erosion Controls

Documentation requirements include the entries in the Inspector’s Daily Reports, which reflect the Inspector’s observations relative to the sediment and erosion control compliance of the site.  A BMP Inventory form is furnished in SS 832 Appendix A to assist in documenting and recording the BMP quantities for payment.  The BMP inventory form in Appendix A is not a substitute for the inspection report described above.

The Contractor is required to provide the Engineer with an inspection report every 7 days and within 24 hours of a 1/2-inch (13 mm) or greater rainfall event throughout the life of the Contract.  Inspection requirements can be reduced to once a month if the SWPPP Engineer certifies that the entire project has been temporarily stabilized and the construction activity will be suspended over the winter.  

Include the following in the inspection report:

§  The OEPA NPDES Permit inspection checklist information (see appendix E, Part III.G.2.i).

§  A map identifying all BMP needed, installed, maintained, or removed since the last inspection report.

§  Certification that all construction activities are compliant with the SWPPP and the signature of the CECI responsible for the inspection. 

§  The signature of the Professional Engineer who sealed the SWPPP is required as part of the inspection report on a monthly basis or when modifications to the SWPPP design are made.

§  Include the certification requirements according to OEPA NPDES Permit Part V.H with all reporting sign offs.

SS-840 Mechanically Stabilized Earth (MSE) Walls

Introduction

MSE walls have been constructed in the State of Ohio for over 25 years.  In previous years, there were special provisions in the Contract that detailed the construction and design requirements.  In the old special provisions, each wall supplier had a unique special provision.  The supplemental specification (SS-840) combines all of the special provisions into one document.

SS-840 is updated frequently.  Check the plans and addenda to see which version is included in the Contract.  If a more recent version is available, consider adopting the new version by a change order.  There may be a cost or savings involved with adopting the new version, depending on what has changed.

Below is a detail of a typical MSE wall application.  This is an elevation view of a MSE wall and bridge.

Figure 840.01.A  MSE Wall Elevation View

For the same bridge, a plan view is shown below.

Figure 840.01.B  Plan View of the MSE Wall and Bridge

MSE wall specifications are different than the normal construction specifications.  There are both design and construction criteria in the specifications.  The plans will detail a three line diagram of the MSE wall structure.  The internal details and the construction shop drawings are submitted after the sale of the project.

This detail shows the reinforcing mesh in general form and the undercut.

Figure 840.01.C  Typical Plan Cross-Section of a MSE Wall

In the detail below, the Designer has laid out the select granular backfill and 203 embankment.

Figure 840.01.D  Layout of the Select Granular Backfill and 203 Embankment

There are applications where the Designer may choose to place a wall on both sides of an embankment as detailed below.

Figure 840.01.E  MSE Walls on Both Sides

General Information

The following figure details the general configuration of the MSE wall system.

Figure 840.01.F  Typical Section of an MSE Wall Structure

Terms

The following are standard terms that will be used throughout this text.

Coping: The coping is used to tie in the top of the wall panels and to provide a pleasing finish to the wall top.  It is cast in place.

Filter Fabric: A geotextile filter fabric is used to cover the joint between panels.  It is placed on the backside of the panel joints.  This keeps the soil from piping through the joints and allows excess water to flow out.

Concrete Leveling Pad: The leveling pad is unreinforced cast-in-place concrete.  The concrete is 24 inches wide, 6 inches thick, and has a minimum compressive strength of 2,500 psi.  Cure the cast-in-place concrete for a minimum of 12 hours prior to placing the first row of facing panels.

Original Ground: The existing ground surface at the site.

Random Backfill: Random backfill is the backfill that is allowed in normal embankment construction.

Select Granular Backfill: Select granular backfill is the granular backfill that meets the gradation, corrosion, unit weight, internal friction angle, and any other requirements.

Soil Reinforcement: Soil reinforcement holds the wall facing panels in position and provides reinforcement for the soil.  The soil reinforcement can be strips, grids, or mesh. The reinforcement can be made of steel (inextensible materials) or polymers (extensible materials).

Spacers: Wall panel spacers are typically ribbed elastomeric or polymeric pads.  They are inserted between panels to help provide the proper spacing.  Proper spacing keeps the panels from having point contact and spalling the concrete.

Wall Facing Panel: Wall Facing panels or panels are used to hold the soil in position at the face of the wall.  The panels are made of precast concrete.

Wall/Reinforcement Connection: This is where the connection is made between the wall facing panel and the soil reinforcing.

Wood Clamps: Wood clamps are pieces of wood with a steel bolt.  It is used to hold the panel in place once the panel is set.  The panel is not released from the crane until the wood clams are in place and tight.

Wooden Spacers: Wooden spacers are used to space the panels at the 3/4 inch-vertical spacing.  The spacer is held between the panels to ensure the joints are not too close or far away.

The wooden wedges should be made from any hard wood.

Wooden Wedges: Wooden wedges are used to help hold the panels at the correct batter during the filling operation.  The wooden wedges should be made from hard wood, such as oak, maple, or ash.

Figure 840.01.G  MSE Wall Parts

Construction (840.06)

The wall system consists of the original ground, concrete leveling pad, wall facing panels, coping, soil reinforcement, select backfill, and any loads and surcharges.  All of these items have an effect on the performance of the MSE wall and are taken into account in the stability analysis. A change in any of these items could have a detrimental effect on the wall.  The construction sequence follows:

Wall Excavation (840.06.C)

There are many instances that the MSE wall is constructed in a cut section.  This means that the excavation behind the wall needs to be supported temporarily in order to construct the wall.  A pay item for cofferdams and excavation bracing will be included in all MSE wall plans, but if it is missing, the specification states that the cost for cofferdams and excavation bracing are included with the MSE wall pay item.  The Contractor is responsible for supporting the wall excavation.  All work to support the excavation or to fill the void behind the wall will be the responsibility of the Contractor.

Figure 840.06.C.1  Excavation and Select Granular Backfill Areas

Figure 840.06.C.1 shows the wall excavation and embankment areas.  All of the area below the dotted line is paid for under wall excavation.  All the area in the reinforced zone is filled with select granular backfill.  The area below the leveling pad is filled with undercut material.  Below is a field view of the same situation.

Figure 840.06.C.2  Area Behind the Wall

Foundation Preparation (840.06.D)

Preparation and Compaction

The MSE wall footprint area needs to be prepared in the leveling pad, soil reinforcement, and select granular backfill areas.

Figure 840.06.D.1  Foundation Preparation

Figure 840.06.D.1 above shows a track hoe excavating down to the MSE wall foundation.  All organic matter, vegetation, slide debris, and other unstable materials, detailed as unsuitable in 703.16, needs to be removed.  Once the unsuitable soil is removed, 1 foot outside of the foot print formed by the leveling pad and soil reinforcement needs to be compacted.  The foundation needs to be compacted to meet the requirements of 203.07.  If the foundation material is granular then the material needs to be compacted by one of the test section methods detailed in S-1015.

Once the foundation is compacted, then the foundation for the wall needs to be graded level for the full-length and width of the leveling pad and the soil reinforcement.

Foundation Evaluation

Once the foundation is compacted, the Department needs to evaluate the foundation.  Contact the District Geotechnical Engineer or the plan design soils consultant to evaluate the foundation.  This can be paid for through continuing services during construction through the project design coordinator.  The DGE or soils consultant will evaluate the soil conditions.  In the design phase, a bearing capacity and stability analysis was performed for the MSE wall based on the plan borings.  This needs to be reevaluated based on the existing soil conditions during construction.  The DGE or soils consultant will make a field visit to the site to determine if the foundation soils found during construction meet the soil conditions designed for in the plans.  They will then report to the Department to give their results.  The Contractor’s pay depends on receiving this report so the Contractor will prompt the Department to make this evaluation.

The project should review the soils’ consultant report.  The project should ensure that the excavated soils match the soil borings performed to design the wall.  If the existing conditions do not match plan soil borings or there are any unusual problems with the report, contact the State Construction Geotechnical Engineer.

Undercut and Drainage

Drainage and the foundation conditions are important parameters of the MSE wall system.  Therefore, many contracts will detail an undercut.  If an undercut is in the plans, the foundation work detailed above should be performed on the foundation of the undercut.

The following sketch details a standard undercut.

Figure 840.06.D.2  Standard Foundation Undercut

Once the foundation of the undercut is compacted, the drainage pipe is constructed.  The plans will detail the pipe with a pay item.  The pipe must be outletted.  There will be at least 50 feet of outlet pipe in the plans to outlet the pipe.  The project will have to look for an outlet if it is not detailed in the plans.  Pipe, manholes, and other items can be used as a drainage outlet.

If the pipe cannot be drained, move the pipe to the outside of the wall until it can be drained.  The dotted pipe above the leveling pad, in Figure 840.06.D.2, represents this pipe.  It is shown on the inside of the wall, but there is no need to put the drain on the inside of the wall.  It can also go on the outside of the wall.  The sand on the inside is free draining.

Figure 840.06.D.3 below shows a 5 foot undercut operation.  The replacement material in this case was a well graded blast rock.  The material of choice for foundation replacement should be Item 203, Granular Material Type C.  The upper portion should be chocked off with at least 1 foot of Item 203, Granular Material Type B.  Geotextile Fabric Type D should be placed below the Granular Material Type C.  This will prevent the piping of fines from the top and the bottom of the Granular Material Type C.

Figure 840.06.D.3  Replacing the Foundation

Leveling Pad Construction (840.06.E)

Once the foundation is compacted and prepared, a 2-foot wide and 6-inch thick un-reinforced concrete pad is constructed.  The purpose of this pad is to serve as a guide for the wall panel erection.  This leveling pad is not intended to provide significant structural foundation support in the final configuration of the wall, but there is significant construction panel loading on the leveling pad.  Therefore, it must be properly constructed and on a firm foundation in order to minimize potential wall movements during the construction of the wall.

Figure 840.06.E.1  Leveling Pad Construction

The leveling pad is important to the construction of the wall, because the leveling pad sets the horizontal and vertical alignment of the wall.  It must be in the correct horizontal position, level, and at the correct grade.

Figure 840.06.E.2  Accurate Leveling Pad Construction is Important

If the final wall is not level, the panels will bind against each other causing spalling of the edges and corners.  If the wall is not started correctly, the finished product is seldom satisfactory.

No more than 2 shims (each 3/16 inch thick) should be required to level the panels on the leveling pad.  If level cannot be obtained with two shims, then the leveling pad and the bottom of the panels needs to be checked.

Figure 840.06.E.3  Improper Shimming

Under no circumstances are bearing pads allowed on the leveling pad.  Bearing pads can create point loads on the panels and allow for movement of the panels during construction.

Figure 840.06.E.4  Bearing Pads are Not Allowed on the Leveling Pad

Care must be taken to ensure the leaving pad is correctly aligned.  The leveling pad is 24 inches wide to allow for some alignment errors and inconsistencies, for example, when going around corners and curves.  In addition, the wider leveling pad will supply more support during construction.

Do not allow any overhanging of the panels off the leveling pad.  If this happens, stop the construction and investigate the problem.  If needed, reconstruct the leveling pad.

Figure 840.06.E.5  Improper Overhang

Leveling pads that change in elevation have special challenges in design and construction.  Figure 840.06.E.6 below details this challenge.  This figure is a general step-up figure with some of the dimensions changing in the new SS-840.

Figure 840.06.E.6  Change in Leveling Pad Elevation

The challenge is to arrange the leveling pad and panels so that when this elevation change occurs, the panel is almost fully supported by the leveling pads.  Multiple elevation changes are even more difficult to construct.  In all cases, a 6-inch maximum overhang along the wall is allowed.  The minimum overhang distance along the wall is approximately 3 inches.

Figure 840.06.E.7  Acceptable if Less than 6 inch Overhang

The concrete leveling pad must cure for at least 12 hours before wall panels can be placed.

Figure 840.06.E.8  Finished Concrete Leveling Pad

Wall Panels Types and Parts (840.04.A)

Wall panels come in many shapes and sizes.  The most common are the square and rectangular.  They can be custom built into any configuration that will fit together.  The front face can have any type of finish, shape, texture, or other surface treatments that can be formed.

Figure 840.04.A  Reinforced Earth Panels

Figure 840.04.B  Rectangular Panels

Figure 840.04.C  Textured Finish Panels

Corner Panels

Corner panels provide a good connection between the two walls and act like slip joints for the wall allowing differential movement between the two walls.

Figure 840.04.D  Corner Panels

Slip Joints

Typically a slip joint is used to handle large differential vertical movement of the wall.  There are two in the figure below, one on each side of the corner section.

Figure 840.04.E  Corner (front) and Slip Joints (One on Each Side)

Handling, Storing and Shipping Panels (840.05.H)

Panels should be stored flat and on spacers or dunnage.  Spacers are typically sent by supplier on pallets of panels.  Spacers protect the galvanized soil reinforcement connections from being bent or damaged by other panels.  Panel faces should be kept away from areas that are muddy to prevent staining of the face of the panel.  The project should ensure that panels don’t have spalling or cracking upon delivery to the site.

Correct storage is shown in Figure 840.05.A.  Note that the dunnage height is more than the soil reinforcement connections to minimize damage.

Figure 840.05.A  Proper Panel Storage with Dunnage

Figure 840.05.B is an example of improperly stored panels.  The panels in this case can get chipped or cracked.

Figure 840.05.B  Improper Panel Storage

The soil reinforcement connections also can get bent.

Figure 840.05.C  Damaged Tabs

Panel Inspection

Panel Dimensions and Tolerances (840.05.G)

When the panels first arrive at the project, the panel documentation needs to be checked.  The panels come with a TE-24.  The documentation required with this TE-24 is a record of final inspection of all precast components and the measurements of the tolerances, strength, and dimensions of all panels.  As one final check, the dimensions need to be randomly checked at the project.  The shipment paperwork, shop drawings, and the actual panel dimensions need to be compared to ensure that issues are found in a timely manner.  The earlier in the process that these problems are found, the easier it will be to correct the issues.  Some of the panel items to pay particular attention to are:

1.        Length, width, and thickness.

2.        Squareness.

3.        Finish.

Physical measurements of the panels are required.  The project should use a tape and carpenters square to check the above.  All of these dimensions have an effect on the Contractor’s ability to construct the wall within the specification tolerances.

Figure 840.05.D  Checking the Squareness of the Panel

Precast Panel Rejection (840.05.J)

Damage to the Galvanized Soil Reinforcement Connections

If the soil reinforcement connections are damaged to the point that it inhibits the soil reinforcement from being attached, then the panel needs to be rejected.  Many times the connection is filled with residual cement or concrete that does not allow the soil reinforcement to be connected.  If this is the case, have the Contractor clean out the connections.  Do not cut the soil reinforcements.

If the connections are bent more than 15 degrees from perpendicular, the panel needs to be rejected.  When bent beyond 15 degrees, the galvanizing is compromised and cannot be repaired.

Damage to the Panels

The panels also need to be inspected for damage.  Panels can be damaged almost anywhere during the manufacturing or construction process.  Many of the chips and cracks are caused by poor handling.  Chips or spalls can be prevented by using nylon straps in the handling process.  Cracks can be avoided by taking care in the handling process.  There is a list of defects and damages in 840.05.H that are sufficient reason for rejecting a panel.  Depending on the severity of the damage, the Contractor may propose a repair.

Figure 840.05.E  Rejected Cracked Panel

Figure 840.05.F  Rejected Lifting Spall

Figure 840.05.G  Repairable Lifting Strap Spalling

Figure 840.05.H  Repairable Handling Spalls

Wall Erection (840.06.G)

Panel Identification

At this point, we have constructed the foundation, added drainage, checked the materials, and constructed the leveling pad.

There is one last step we need to perform before we construct the wall; the wall and shop drawings must be checked to ensure that the correct panels are being used in the correct location along the wall.  Depending on the wall height, the panel shape, or design, the number of soil reinforcement connections on the back of the panel may vary.  The panels with the most connections will typically be in the lower panels of the wall.  In the upper portions of the wall, the number of connections may be less.  It is important that the panels are used in their proper position.  Below is a typical shop drawing showing the panel organization.

Figure 840.06.G.1  Typical Panel Erection Shop Drawing

The erection drawings have a numerical code on each panel that depicts its position in the wall.  In the above shop drawing, the letter A denotes full-height panels in the first row and the subsequent rows until the shape changes as the panel is just below the coping.  The letter B denotes half-height panels in the first row.  The codes HX, F11, L11, KX, K, E, EX, HJJ, KJJ, LJJ, DJJ, and EJJ denote panels just below the coping. Note the combination of letters. R or L will be used to denote the right or left side of the wall.  A number that follows the letters denotes the number of tie strips required for the panels.  Below is a code that details the panel letter and numerical system.

Figure 840.06.G.2  Code for Panel Placement (Reinforced Earth)

The code that is detailed above is for Reinforced Earth walls.  The code for other wall systems will be different, and the code for a particular wall system may change at any time.  The codes are marked on the back of the panels for easy reference during construction.  Below is a photo of the marking on the back of a panel.

Figure 840.06.G.3  Actual Panel Markings

The above markings show piece A has 3 tie strips and is on the right side of the wall.  Other required markings include date of manufacturing, production lot number, and the precaster’s and accredited manufacturer’s inspection and acceptance marks.

Placing the Panels

Picking up the panels is an important aspect of the construction procedure.  If the panels are not properly picked up, spalling or cracking can occur.  The figure below shows the correct method of picking up the panels.  The crane lifts the panel so that no concrete to concrete contact occurs.

Figure 840.06.G.4  Picking up the Panels

The correct placement of the first row or two of panels is very important.  When the panel construction is not started correctly, the finished product is rarely satisfactory.

In the figure below, a chalk line is placed on the leveling pad to properly align the panels along the leveling pad.  Sometimes a 2×4 is used to align the panels.  Adjust the alignment using a crowbar as shown below.  At this point, the panel is still supported by the crane.

Figure 840.06.G.5  Proper Placement

As one last check of the horizontal alignment, the panel to panel horizontal offset needs to be checked. Use a straightedge across the panel horizontal joints to ensure that the panel to panel horizontal offset does not exceed 1/2 inch.

The first row may be composed of both half- and full-height panels.  A photo of full- and half-height panels is shown below.  The panels need to be in proper alignment and level.

Figure 840.06.G.6  Half Height Panels

Horizontal Leveling

Once the panel is placed on the leveling pad, the panel needs to be leveled horizontally.  A 6-foot level rod is placed on the top surface of the panel to determine if it is level.

Figure 840.06.G.7  Proper Horizontal Leveling

If it is not, shims are placed under the panel in order to make the panel level.  Galvanized metal washers or rubber shims are allowed.  A maximum 3/8 inch in total shim height, at any location, is allowed.  If more shims are required, then the leveling pad is not level or the panel bottoms are not flat.  In either case, the issue is the Contractor’s responsibility to resolve.

Figure 840.06.G.8  Metal Shims to Level the Panels

Horizontal Joint Spacing

Without the correct joint spacing, panel corners will crack and spall with the wall settlement.  Spacing blocks must be used.  As the panels are placed together, the 3/4-inch spacers are placed in the joints.  The panels are maneuvered so that there is contact between both panels and the joint spacer.  The required joint spacing is 3/4 inch ± 1/4 inch.  If this spacing cannot be achieved, the Contractor is required to submit an action plan to correct the problem.  The spacer is shown in the figure below.  If the panel is moved during the joint spacing adjustment, then the horizontal leveling should be checked again.

Leave the horizontal spacers in until half of the panel height is filled with backfill.

Figure 840.06.G.9  Wooden Joint Spacers

Vertical Alignment

The panels need to be set with a backward batter toward the inside of the wall.  The typical batter is about 1/8 inch per foot of panel height or about 1/2 to 1 inch per panel.  Compacting the backfill behind the wall pushes the panel outward, so the panel will be vertical once the fill is placed against it.  The amount of batter is adjusted for the site conditions, such as backfill properties; the finer sand may require a more batter.  If a fine graded material, such as foundry sand is used, then it may require a 1-inch batter.  A well-graded, crushed limestone may require a 1/2-inch batter.

Figure 840.06.G.10  Batter Check

A level with a batter spacer is placed on the outside or inside of the wall.  Use the outside of the wall unless textured.  The batter spacer can be used on the top or bottom of the level.  If the level is used on the outside of the wall, the batter spacer is used on the top of the level.  If the level is used on the inside of the wall, the spacer is used on the bottom of the level.  The spacer is usually duct taped on to the level at a thickness of the batter.  In the figure below, it shows the batter spacer being used on the inside of the wall.

Figure 840.06.G.11  Vertical Leveling Spacer on the Inside of the Wall

The level can also be used on the outside of the wall as shown below.

Figure 840.06.G.12  Vertical Batter on the Outside of the Wall

Vertical and horizontal alignments and joint spacing needs to be checked one last time prior to temporarily locking the panel in place.  For the entire time the horizontal leveling, joint spacing and vertical alignment is being adjusted, the panel is still suspended from the crane so that the panel is not damaged.

Triangular Wedges and Wood Blocks

Wooden triangular wedges are used to lock the panel into vertical alignment once the wall is battered with the level.  The wedges are shown below on the leveling pad.

Figure 840.06.G.13  Wooden Wedges for Vertical Alignment

No more than three levels or rows of the wooden wedges should be placed in the wall without removing the lower row.  If more than three levels of wedges are used they may become bound in the wall making them very difficult to remove and can cause the panel to spall.

Wooden clamps are used to hold the panels together.  Wooden clamps are two pieces of wood held together with a long bolt.  The bolt is tightened to hold the panels together.

Figure 840.06.G.14  Wooden Clamps

Triangular wedges are also used in combination with the clamps to secure the panels as shown in the figure below.

Figure 840.06.G.15  Triangular Wedges and Wooden Clamps

External bracing is required for the first row of panels to maintain stability and alignment.  Typical bracing is shown below.

Figure 840.06.G.16 Proper Bracing

At this point, the geotextile fabric and the select granular backfill are placed to the height of the wooden clamps.  These steps will be described in detail later.

When panels are placed on one another, a horizontal bearing pad is used to separate the panels.  A minimum of two bearing pads are used.  The horizontal joint should be 3/4 inch at this point.  Some Accredited Wall Systems may supply thicker bearing pads.  This is anticipation of the bearing pads deflecting under the load of the wall.  Check the accepted wall shop drawings to ensure that the thicker pads are allowed.

Figure 840.06.G.17  Bearing Pads on the Second Row

Subsequent panel rows are placed between panels that were previously placed. The ability to properly space and align these rows relies on the proper placement of the lower rows.  All of the error produced by the lower rows is propagated upward and is difficult to correct.  The same leveling, joint spacing, vertical, and horizontal alignment applies to all the rows.

Figure 840.06.G.18  Panel Placement

Panel-to-panel vertical offset needs to be checked as soon as the next row of panels is placed.  Use a straightedge across the vertical joints to ensure that the offset between panels is less than 1/2 inch.

Figure 840.06.G.19  Second Row of Panels Placed

The process starts all over again as crow bars are used to align the next row of panels.

Figure 840.06.G.20  An Existing Joint Offset Problem

Alignments need to be checked periodically to ensure proper alignment.  This will ensure that problems are spotted early and corrections can be made before the panels get too far out of alignment.

Figure 840.06.G.21  Wall Alignment

As stated before, the panels are battered back so that the fill placement can move them forward into a vertical position.  After the fill is placed, check the vertical position of the wall. After the third row of panels is placed, use a plumb bob to check the vertical alignment.  Hold the plumb bob at the top of the panel and measure the out of plumbness, as shown below.

Figure 840.06.G.22  Checking Vertical Alignment with a Plumb Bob

The tolerance is 1/2 inch in 10 feet.  By using a 10-foot straightedge and a level or a plumb bob, this tolerance can be measured.  At no point along the straightedge can any portion of the panel be more than 1 inch away from the string or straightedge.

Figure 840.06.G.23  Measure from the Wall to the String (Out of Plumb Here)

A summary of the wall erection tolerances are listed below:

1.        Vertical Tolerance: 1/2 inch overall and 1 inch at any point.

                Use a 10-foot straightedge,

2.        Horizontal Tolerance: 1/2 inch overall and 1/2 inch at any point.

                Use a 10-foot straightedge.

3.        Panel to Panel Tolerance: 1/2 inch horizontal and vertical.

                Use a 6-foot straightedge.

Figure 840.06.G.24  Panel Tolerances

Filter Fabric Placement and Inspection

Filter fabric is placed across the joints so that the granular backfill does not leak through the joints to the outside of the wall.  The minimum lap on each side of the joint is 1 foot on each side of the joint and 1 foot along any cut piece of fabric along the joint.  These requirements apply to horizontal and vertical joints.

The fabric is cut in lengths to cover the horizontal and vertical joints.  Once the fabric is cut, the fabric is laid on a flat surface.  An adhesive is used to hold the filter fabric in place until the select granular backfill is placed over the joints.  A thick bead of the adhesive, approximately 1/2 inch in diameter, is applied around the entire perimeter of the fabric, about 2 inches from the edges of the fabric.  See the figure below.

Figure 840.06.G.25  Correct Application of the Adhesive

Figure 840.06.G.26  Fabric Completely Covering the Joints

Once adhesive is applied to the fabric, it is immediately placed on the wall.  Ensure that the fabric is placed on the wall before the adhesive dries. The fabric needs to fully engage the wall at all locations to ensure that the sand does not leak through the joints.

Figure 840.06.G.27  Wrong Application of the Adhesive on the Wall

As shown above, randomly placing adhesive on the wall does not ensure that the joint is properly sealed.  More adhesive is not necessarily good.  Correctly applied adhesive and the appropriate placement of the fabric is the solution.

In the past, some projects have only glued the top portion of the fabric applied to a horizontal joint.  This method should be discontinued and not be allowed.

Figure 840.06.G.28  Partial Gluing (Do not Allow this)

Small tears or wrinkles in the fabric can cause leaking of the sand.  Any leaking of the sand through the joints is not tolerable.  Leaking sand is like a leaky water pipe; it never gets better with time, it only gets worse.

Once the fabric and the backfill are placed, the project should go around to the front of the wall to inspect the joint spacing and the fabric’s ability to hold the sand behind the wall.  Take a flashlight and inspect the joints.  Look to see if the fabric is in place and holding the sand back.

Look for deposits of sand in the horizontal and vertical joints, as shown below.

Figure 840.06.G.29 Sand in the Joints on the Outside of the Panels

Sand deposits may be caused by sand falling over the wall during construction or the sand is leaking through the joints.  By carefully inspecting the joints, the source of the sand deposit will be found.  In the figure below, the sand is leaking out of the joints and being deposited on the ground.

Figure 840.06.G.30  Sand Falling from Several Joints

After further inspection of the wall from behind, it was found that the fabric was not placed in the upper portion of the MSE wall.  This project was about three-years-old at the time of the inspection.  A thorough inspection during the construction of the wall would have prevented this maintenance problem.

Figure 840.06.G.31  No Fabric Placed Behind the Wall

Below is a photo of a wall, which was taken shortly after construction.  As you can see, there are sand deposits at the bottom of the slip joints.  In this case, the fabric was either not placed or improperly placed.

Figure 840.06.G.32  Sand Piles around Slip Joints

In the figure below, looking behind the wall at a typical slip joint during construction, you can see that the fabric has to go around a bend.  Careful construction in this location is required.  When placing fabric around corners or obstructions, leave the fabric loose so that it does not tear during the placement of the backfill in the corner.

Figure 840.06.G.33  Fabric Placement around a Slip Joint

There are a lot of other items of work that obstruct the proper placement of the fabric in this situation.  In the figure below, there are the reinforcing steel, wooden clamps, and a settlement plate that the fabric needs to go around.  There is ample opportunity for sand to leak around the fabric if we are not careful.

Figure 840.06.G.34  Obstructions near a Slip Joint

The joint spacing needs to be reexamined in the front of the wall.  We have previously checked and recorded the joint spacing when the panels were constructed.  There may be cases where after the wall is constructed, the joint spacing is wider than the allowable 3/4 inch plus 1/4 of an inch.

Figure 840.06.G.35 Wide Joint and Exposed Fabric

The joint gap in the above figure is almost 1-3/4 inch.  The gap is wider than the panel’s ship lap, therefore, exposing the fabric.  The width of the ship lap is about 1-1/2 inches.  In the above case, the Contractor needs to be instructed to place expansive foam and caulk to the joint to prevent the fabric being exposed to sunlight.

Sunlight can cause the fabric to deteriorate with time, whether direct or indirect.  A flashlight is used to minimize sunlight exposure to the fabric.  A flashlight is held perpendicular to the joints, about 6 inches away from the joint.  The described flashlight test is shown in the figure below.

Figure 840.06.G.36  Flashlight Test

If the light from the flashlight can be seen on the fabric, then the joint needs to be sealed.  Expanding foam and caulk is used to cover the fabric.

There have been instances where, after the wall has been constructed, the fabric is destroyed during water jetting operations.  Water jetting is used to clean the panels prior to sealing; therefore, examine the joints after the sealing operation.

As a final note on the wall construction, continue to monitor the wall throughout the duration of the project. The wall is designed and constructed to tolerate movement.  Too much movement is detrimental to the wall and the structural items around the wall.

Select Granular Backfill Placement (840.06.I)

Material

The granular backfill materials have special requirements that are not normally associated with granular material in other items of work.  There are material requirements such as pH, resistivity, chloride, and sulfate levels.  These requirements minimize the corrosion of the metal soil reinforcement.  The project and district test lab need to review and evaluate the test data for these requirements.  Ensure that the test results meet the specification requirements and that the correct tests were taken on the materials.  If the backfill material does not meet these requirements, then there is a high probability that the metal soil reinforcement will prematurely corrode and the life of the MSE wall will be shortened.

Another requirement is the internal angle of friction. The internal angle of friction is critical to the design of the wall.  The wall design and the factor of safety are sensitive to numerical value of the friction angle.  The factor of safety can change dramatically with only a few degrees of friction angle change.  The design friction angle is 34 degrees.  The test ensures that the design assumption is valid.

The specification allows the use of granular material Type 2 which is old Item 310 material.  It can be very fine sand or a coarse 304 type material.  Since economics drives the material choice, the vast majority of the time sand is used.

The specification also allows the use of Item 304 material.  This material is a well graded and very stable material.

It is a requirement to use the Item 304 material for the first 3 feet of backfill behind the wall.  This is a stronger material and is more resistant to the influences of water.  After the first 3 feet are placed, the sand or the 304 may be used.

Select Granular Backfill Placement and Compaction

The below placement and compaction procedures were developed to produce uniform compaction of the select granular backfill (SGB). Uniform placement and compaction of this material is essential in order to keep uniform pressure against the wall as it is constructed.  Unnecessary compaction or non-uniform compaction of this material can create bulges in the wall or loose areas in the backfill behind the wall.  This procedure is to be followed all the way to the top of the wall.

On the initial row of panels (and only the initial row of panels) the backfill is not placed against the panel until the first layer of soil reinforcement has been connected and the initial layer of backfill is placed and compacted on top of the soil reinforcement.  This is to keep the bottom of the panels from “kicking out.”  If the SGB cannot be compacted effectively below the first row of soil reinforcement, because some manufacturers may have mesh that we cannot compact through, then the wall supplier will need to design a kicker to prevent the wall from kicking out at the bottom.

Figure 840.06.I.1  Backfilling for the First Panel Only

Once the backfill is placed and compacted to the elevation of the first layer of soil reinforcement as shown in Figure 840.06.I.1, the soil reinforcement is connected.  Then the next loose lift is placed on top of the soil reinforcement 3 feet away from the wall.  The material is then leveled by moving it parallel to the wall and windrowing the material toward the soil reinforcement ends and away from the wall.  See Figure 840.06.I.2 for the spreading operation details.  This SGB material which is 3 feet away from the wall is then compacted in the same way as it was placed.

Figure 840.06.I.2 Procedure for SGB Placement and Compaction

Once this is completed, the void is filled and compacted next to the wall to the elevation of the soil reinforcement.  The material void left above the soil reinforcement is then placed and compacted.  Place and compact this inner most 3 feet as detailed in Figure 840.06.I.3.  Within 3 feet of the wall, the SGB is compacted with six passes of a mechanical tamper or vibratory plate compactor.  The compaction equipment should have a centrifugal force between 1/2 to 2 tons.

Figure 840.06.I.3  Place and Compact the SGB Next to the Facing Panels

Use the procedure detailed in Figures 840.06.I.2 and 840.06.I.3 for the SGB placement and compaction procedure for the remaining sections of wall.

The SGB is placed in maximum 8-inch loose lifts.  It may be helpful to mark the lift thicknesses on the back side of the wall panels.  The action of moving the SGB parallel to the wall and windrowing or compacting the material toward the reinforcement ends and away from the wall takes out the slack in the reinforcement and locks the reinforcement and the panels in position.

Figure 840.06.I.4 Improper Spreading Technique

(From back to front is improper)

Any slack in the reinforcement should be removed to avoid excessive panel movement.  With geogrid soil reinforcement, some tension needs to be applied to the reinforcement by means of a kicker tension device or a rod during this backfill placement.

Figure 840.06.I.5 Final Compaction Operation Next to the Wall

Consistent placement and compaction of SGB are one of the keys to a good performing MSE wall.

Inspection and Compaction Testing (840.06.N)

No compaction testing is performed on the SGB within 3 feet of the wall. For the SGB, more than 3 feet from the wall facing panels, smooth-drum vibratory rollers weighting between 6 and 10 tons are required to compact the material.  The compaction testing is performed according to Supplements 1015 and 878.

Supplement 878 details the general inspection and compaction testing requirements when these services are hired through the Contractor.  All of the inspection and compaction procedures that are required for ODOT inspection personnel are required for the Contractor’s personnel under S-878.  A trained compaction and inspection person is required under this specification.  All of the Department inspection and compaction forms are to be used.

Supplement 1015 details the inspection and compaction procedures to be employed during the work.

At the beginning of the work, a test section is constructed to determine the density requirements for the select granular backfill. The moisture requirements are determined by using the moisture density curve for the Method A test section.  For the Method B test section, the moisture requirements are determined by constructing several test sections at different moisture contents.  For determining which test section is used, see section S-1015.

The select granular material is compacted between 3 percent below and optimum moisture content.  If additional water is required after spreading the material, then water must be added to meet these requirements.  The moisture content of the select granular backfill material prior to and during compaction is to be uniformly distributed throughout each layer of material.  If watering is required after spreading, the project should dig up the material to ensure that this requirement is met.

Figure 840.06.N.1 Taking a Compaction Tests

Once the moisture content is correct, the test section is constructed to determine the density requirements for the remaining areas of the select granular backfill. This test section is approximately 40 square yards.  This test section is compacted until a maximum density is achieved.  The number of passes and the maximum density is used in the remainder of the work. A minimum of 98 percent of the maximum density is required.  A new test section should be constructed if the compaction tests are not close to the maximum value. Use the same number of passes if the material or foundation conditions change.

In the figure below, the compaction starts 3 feet away from the wall and proceeds to the back of the soil reinforcement.  In the background, the area within 3 feet from the wall is compacted after the roller compaction is complete.  This procedure is detailed in the previous section.

Figure 840.06.N.2 Smooth-drum Vibratory Compaction Equipment

Wall Drainage (840.06.F)

At the end of each day’s operation, the Contractor is to shape the last layer of backfill to allow rainwater to runoff away from the wall face.  The drainage system is under or in front of the wall. This will permit the water to dissipate from the system.  The SGB of the wall can be drained laterally to dissipate out to the sides.  Drainage problems can develop similar to the figure below.

Figure 840.06.F.1  Washout around the Soil Reinforcement

Water ponding in front of the wall has been a problem is the past.  In the figure below, you can see the ponding of the water in front of the wall.  This is not acceptable.

Figure 840.06.F.2  Water Ponding in Front of the Wall

It is required to pump the water out of this area immediately after the water is ponded.  In addition, once the wall is erected up to the ground elevation, this void is filled with embankment material.  This will further stabilize the wall.

If water is ponding behind the wall during construction as shown below:

Figure 840.06.F.3 Water Ponding Behind the Wall

Then collect the water by using a drainage curtain as detailed below:

Figure 840.06.F.4  Drainage Blanket

Side slope erosion has been a problem in the past.  One solution has been to construct 2 feet of embankment on the side slopes. This will bury the highly erosive select granular material and erosion can be minimized.

Figure 840.06.F.5 Protection of the Erosive Side Slopes with Embankment

Soil Reinforcement Installation (840.06.H)

Soil Reinforcement Storage

The soil reinforcement is used to tie the wall to the soil.  Like the panels, the soil reinforcement should be stored on dunnage and carefully handled to prevent damage.  Damage may include bending of the metallic reinforcement and damaging the galvanization.  The geogrid soil reinforcement should not be torn, cut, left in the sun, or otherwise damaged.

No equipment should be allowed to run directly on the reinforcement.

Figure 840.06.H.1  Reinforcement Storage on Dunnage

The project should check for required length and gauge of steel reinforcement.  Check the condition of steel reinforcement upon delivery to the site.  Below is a typical plan view of the soil reinforcement on a project.  The length of the reinforcement from the wall is directly proportionate to the height of the wall.  The wall height below is the highest in the center and the length of the reinforcing is the longest.  The length of the reinforcing cannot change from the bottom to the top of the wall.  It can only change along the wall due to changes in the height or design changes.

Figure 840.06.H.2  Typical Reinforcement Layout

Below is a detail of a cross-sectional view of the soil reinforcement in the same wall.  Notice the soil reinforcement connection to the wall and regular intervals.  The length of the reinforcement is the same from the bottom of the wall to the top of the wall.  Many of these walls are placed below an abutment as detailed below. 

Figure 840.06.H.3  Cross-Section of the Soil Reinforcement Layout

Below are the reinforcing mesh codes for a Foster wall.  These codes were used on past projects.  For Foster walls, the reinforcing mesh will change frequently.  The project should familiarize themselves with the codes on the shop drawings and ensure that the correct mesh types are placed in the proper location.

The figure below details the wire mesh codes.  Careful review of these keys is required by the project.

Figure 840.06.H.4  Reinforcing Mesh Details

Below is a sample of how the reinforcing mesh is laid out as it relates to the panels.  The panels are numbered in the example and the type of reinforcing mesh is detailed beside the panel type.

Figure 840.06.H.5  Reinforcing Panel and Reinforcing Key

Typically, the reinforcement is placed perpendicular to the wall face. Any slack in the reinforcement should be removed.  The geogrid soil reinforcement should have some tension placed in the reinforcement.  By using the placement and compaction procedure detailed in the previous section, it will keep the tension in the soil reinforcement.

Once the fill is compacted to the elevation of the soil reinforcement, the soil reinforcement can be attached to the facing panels and placed perpendicular to the face of the wall on top of the compacted material.

Connections

Connecting the soil reinforcing to the wall is relatively simple operation.  There are three connections that will be detailed below.

Reinforced Earth Connection

A Reinforced Earth wall’s connections and soil reinforcement consist of galvanized strips, tabs manufactured in the wall, and nuts and bolts to connect them.  There are tabs with holes that stick out of the wall about 3 inches.  The tabs have a top and bottom and go around the strips when they are connected.

Figure 840.06.H.6  Reinforced Earth Connections and Strips

At times, there is concrete inside the tabs that make it difficult to place the strips inside the tabs.  The concrete needs to be cleaned out to line up the holes.  Many times the Contractor will cut the strips instead of cleaning out the concrete.  Do not allow the strips to be cut in the field.  This can reduce the strength of the connection. Also, the galvanizing of the strip will be compromised and the strip will prematurely rust.

Figure 840.06.H.7 Tabs for Reinforced Earth Connections

Once the holes are lined up, the bolt is inserted from the bottom up and the nut is tightened.  By placing the bolt from the bottom, it is easy to see if the nut has been placed on the connection.

Figure 840.06.H.8 Bolted Reinforced Earth Connection

Below are multiple strips connected to the wall for a Reinforced Earth wall.  Leaving the select granular backfill lower at the tabs is acceptable.  The select granular backfill needs to be as close to the strips as possible for all wall types.

Figure 840.06.H.9 Reinforced Earth Multiple Connections to the Wall

Wire Mesh Connection

The connection for steel wire mesh soil reinforcement consists of hooked eyelets in the panels and reinforcing mesh with two transverse bars at the end.  The end of the wire mesh is laid with the two transverse bars resting on top of the hooked eyelets.    A rod is inserted through the eyelets, locking the mesh into place, as shown below.  Wooden wedges are then hammered between the wall and the mesh to put the eyelets in full contact with the mesh and the soil reinforcement in tension.

Figure 840.06.H.10 Wire Mesh Type Connection

Below is a typical layout of the soil reinforcement of a wire mesh wall.

Figure 840.06.H.11 Mesh Steel Laid Out

Geogrid Soil Reinforcement Connection

The connection for geogrid soil reinforcement consists of short sections of geogrid cast into the panels and a plastic bodkin bar.  The ribs of the geogrid soil reinforcement are meshed with the short sections of geogrid that are cast into the panels. The plastic bodkin is then weaved between the two sets of ribs and the soil reinforcement is pulled tight.  The completed connection is shown below.

Figure 840.06.H.12 Geogrid Soil Reinforcement Connection

Figure 840.06.H.13 Overview of Geogrid Soil Reinforcement

Obstructions

There are times when the soil reinforcements have to go around obstructions.  It is not acceptable to simply leave out the reinforcement at that location.  This would create a weak location along the wall.

At horizontal obstructions, such as pipes, the reinforcement should not be angled more than 15 degrees up or down.  All situations that exceed 15 degrees must be detailed on the accepted shop drawings or acceptable to the Office of Geotechnical Engineering.  The soil reinforcement must have a 4 inch clearance above or below the obstruction.  When clearing horizontal obstructions, the reinforcement should be smoothly curved around the obstruction.  The reinforcement should not be kinked at any time.

The detail below shows a horizontal obstruction lower than the soil reinforcing and connection.

Figure 840.06.H.14  Soil Reinforcement going over a Horizontal Obstruction

The detail below shows a horizontal obstruction higher than the soil reinforcing and connection.

Figure 840.06.H.15 Soil Reinforcement going under a Horizontal Obstruction

The photo below shows the soil reinforcement going under a storm sewer line.

Figure 840.06.H.16  Soil Reinforcement going under a Storm Sewer Line

At vertical obstructions, such as piles or catch basins, if the reinforcement must be splayed more than 15 degrees for steel strips or 5 degrees for geosynthetic strips from perpendicular to the facing panels, the accepted shop drawings should detail a modification.  All situations that exceed the 15 or 5 degree limits must be detailed on the accepted shop drawings or acceptable to the Office of Geotechnical Engineering.  It may require additional reinforcement length to meet design.

Figure 840.06.H.17  Soil Reinforcement Splayed Around Piles

In the detail below, the soil reinforcement was designed around the inlet by using a galvanized angle in front of the inlet and keeping the reinforcing steel perpendicular to the wall.  Again, this would have to be detailed on the acceptable shop drawings.

Figure 840.06.H.18 Typical Details for Obstructions

Below is a photo of the galvanized angle in front of the catch basin to allow the soil reinforcement to be placed around the catch basin.

Figure 840.06.H.19 Field Example of the Reinforcing Around an Obstruction

In the detail below, the reinforcing mesh is cut and splayed around the inlet.  No angle is required in front of the inlet.

Figure 840.06.H.20  Cutting the Mesh to go around the Obstruction

Coping (840.06.K)

The coping is placed on the top of the wall.  It is used to smooth out the appearance of the top of the wall and to connect adjacent panels at the top of the wall.  The wall is completed when the coping is properly installed on top of the wall.  The coping has to be cast in place on the top of the wall.

Here is the typical form and reinforcing steel for the coping.

Figure 840.06.K.1  Forming the Coping

Moment Slab

The moment slab is put on the top of the wall to prevent vehicles from going off the roadway.  It must have a large support system to resist these loads.  The reinforcing steel is shown below.

Figure 840.06.K.2 Moment Slab Reinforcing Steel

The finished moment slab is shown below.

Figure 840.06.K.3 Completed Moment Slab

If your project has a concrete pavement on top of the wall, there may be a problem with crack propagation of the barrier joints on to the pavement.  Review these details carefully and make adjustments as required.

Figure 840.06.K.4  Align the Joints of the Barrier and the Concrete Pavement

Design Conflicts, Design and Construction Loads

Before the actual start of construction of the wall, the various parts of the plans (shop drawings, drainage, lighting, etc.) need to be compared to the contract wall plans to check for conflicts.  A conflict may not have been noticed in the design stage.  If the plans show heavy loads on the wall and the shop drawings do not indicate it, the Office of Geotechnical Engineering should be contacted.  The Designer may have missed loadings from various types of structures.  If they did not take these loads into consideration, the wall could bow or even fail.  This also can happen for temporary loads that the Contractor may impose, such as pile driving.

Final Checks

There are various items that need to be evaluated at the end of the project, such as sand leaking out of the joints, open joints, exposed fabric settlement, and more.

There are multiple PowerPoint presentations on the ODOT website.  The websites are as follows:

http://www.dot.state.oh.us/Divisions/ContractAdmin/Contracts/Conaway/Forms/AllItems.aspx

http://www.dot.state.oh.us/Divisions/Engineering/Structures/standard/MSE/Pages/default.aspx

Checklists

The following is a general checklist to follow when constructing a Mechanically Stabilized Earth wall (MSE wall). The answer to each of these should be yes unless the plans, specifications, or specific approval has been given otherwise.

YES NO

  ¨    ¨  1.   Has the Contractor submitted wall shop drawings?

  ¨    ¨  2.   Has the Contractor submitted select granular backfill certified test data?

  ¨    ¨  3.   Has the Contractor supplied a wall supplier’s construction manual?

  ¨    ¨  4.   Have the shop drawings been accepted?

  ¨    ¨  5    Do we have the correct panels (shape, size, and soil reinforcement connection layout) per the accepted shop drawings?

  ¨    ¨  6.   Do we have the correct reinforcement (proper length and size)?

  ¨    ¨  7.   Have the panels and the reinforcement been inspected for damage as outlined in the specifications?

  ¨    ¨  8.   If any panels or soil reinforcement were found damaged, have they been rejected or repaired in accordance with the specifications?

  ¨    ¨  9.   Are the panels and the soil reinforcement properly stored to prevent damage?

  ¨    ¨  10. Has the MSE wall area been excavated to the proper elevation?

  ¨    ¨  11. Has the foundation been properly evaluated?

  ¨    ¨  12. Has the drainage for the wall been installed?

  ¨    ¨  13. Has the leveling pad area been properly excavated?

  ¨    ¨  14. Has the leveling pad been set to the proper vertical and horizontal alignment?

  ¨    ¨  15. Has the leveling pad cured for a minimum of 12 hours before any panels are set?

  ¨    ¨  16. Is the first row of panels properly placed? Do they have proper spacing, bracing, tilt, and where required, do they have the spacers installed?

  ¨    ¨  17. Has the proper filter fabric and adhesive been supplied?

  ¨    ¨  18. Is the filter fabric being properly placed over the joints?

  ¨    ¨  19. Is the adhesive being applied to the fabric then onto the wall?

YES NO

  ¨    ¨  20. Is the filter fabric being stored properly (stored out of the sunlight and protected from UV radiation)?

  ¨    ¨  21. Is the Contractor using the correct panels (correct size, shape, and with the proper number of connections) for that panel’s wall location and elevation?

  ¨    ¨  22. Is the fill being placed and compacted in 8-inch loose lifts?

  ¨    ¨  23. Is the equipment being kept off of the soil reinforcement until a minimum of 8 inches of fill is placed?

  ¨    ¨  24. Are the lifts being placed by the proper method and sequence?

  ¨    ¨  25. Is the fill being compacted by the correct equipment and in the correct pattern?

  ¨    ¨  26. Is the proper compaction being met?

  ¨    ¨  27. Is the soil reinforcement being properly connected (connections tight and all of the slack in the soil reinforcement removed)?

  ¨    ¨  28. Is the soil reinforcement in the proper alignment?

  ¨    ¨  29. Is the vertical and horizontal alignment being checked periodically and adjusted as needed?

  ¨    ¨  30. Is the Contractor removing the wooden wedges as per the specifications? (The wooden wedges shall be removed as soon as the panel above the wedged panel is completely erected and backfilled.)

  ¨    ¨  31. At the end of each day’s operation, is the Contractor shaping the last layer of backfill to permit runoff of rainwater away from the wall face or providing a positive means of controlling runoff away from the wall, such as temporary pipe, etc.?

  ¨    ¨  32. Has the Contractor backfilled the front of the wall?

  ¨    ¨  33. Is the coping being installed correctly?

MSE Wall Construction Do’s and Don’ts

1.        Review approved shop drawings.

2.        Review the Section 840 in the MOP for Mechanically Stabilized Earth (MSE) walls.

3.        Verify leveling pad elevations.

4.        Confirm fill material has been tested and approved before it is brought to the job site.

5.        Inspect panels.

6.        Inspect soil reinforcement for damage.

7.        Reject all panels that are not in compliance with the plans and specifications.

8.        Ensure panels, soil reinforcement, and filter fabrics are properly stored to prevent damage.

9.        Ensure the reinforcing can go around all obstructions with less than 15 degrees of splay.

10.     Install panels in accordance with the plans and specifications.

11.     Place and properly compact fill in accordance with plans and specifications.

12.     DO NOT use thick fill lifts.  Fill lifts thicker than 8-inch loose lifts require more energy to compact and may move the panels out of alignment.

13.     Use corner panels at all corners. If corner panels are not indicated on the plans, the designer should be notified.

14.     Metallic soil reinforcement strips should not be splayed more than 15 degrees from normal.  Geosynthetic soil reinforcement strips should not be splayed more than 5 degrees from normal. If reinforcement needs to be splayed more than the 15 or 5 degree limits, notify the designer.

15.     Check the batter of the panels often. Adjust accordingly. The vertical alignment of the panels below the panels being installed may be affected by the compaction of the soil behind the panels being installed.

16.     Check overall batter regularly.

17.     When attaching filter fabric to the back of the panels, the adhesive shall be applied to the fabric, and then attached to the panel.

Out of Tolerances Conditions and Possible Causes Criteria

The following is taken out of FHWA’s Publication, “Mechanically Stabilized Earth Walls and Reinforced Soil Slopes Design & Construction Guidelines,” NHI Course No. 132042.

MSE structures are to be erected in strict compliance with the structural and aesthetic requirements of the plans, specifications, and contract documents. The desired results can generally be achieved through the use of quality materials, correct construction/erection procedures, and proper inspection. However, there may be occasions when dimensional tolerances and/or aesthetic limits are exceeded.  Corrective measures should quickly be taken to bring the work within acceptable limits.  Presented below are several out-of-tolerance conditions and their possible causes.

Table 840.A – Out-of-Tolerance Conditions and Possible Causes

Distress

Possible Causes

1. Distress in wall:

Differential settlement or low spot in wall.

Overall wall leaning beyond vertical alignment tolerance.

Panel contact, resulting in spalling/chipping

Foundation (subgrade) material too soft or wet for proper bearing.  Fill material of poor quality or not properly compacted.

2. First panel course difficult (impossible) to set and/or maintain level.

Panel-to-panel contact resulting in spalling and/or chipping.

Leveling pad not within tolerance.

3. Wall out of vertical alignment tolerance (plumbness), or leaning out.

Panel not battered sufficiently.

Oversized backfill placing and/or compaction equipment working within 3 foot zone of back-of-wall facing panels.

Backfill material placed wet of optimum moisture content.  Backfill contains excessive fine materials (beyond the specifications for percent of materials passing a No. 200 sieve).

Backfill material pushed against back of facing panel before being compacted above reinforcing elements.

Excessive or vibratory compaction of uniform, medium-fine sand (more than 60 percent passing a No. 40 sieve).

Backfill material dumped to close to free end of reinforcing elements, then spread toward back-of-wall, causing displacement of reinforcements and pushing panel out.

Shoulder wedges not seated properly.

Shoulder clamps not tight.

Slack in reinforcement to facing connections.

Inconsistent tensioning of the geosynthetic reinforcement.

Localized over compaction

4. Wall out of vertical alignment tolerance (plumbness) or leaning in.

Excessive batter set in panels for select granular backfill material being used.

Inadequate compaction of the backfill.

Possible bearing capacity failure.

5. Wall out of horizontal alignment tolerance, or bulging.

Backfill material placed wet of optimum moisture content.  Backfill contains excessive fine materials (beyond the specifications for percent of materials passing a No. 200 sieve).

Backfill material pushed against back of facing panel before being compacted above reinforcing elements.

Excessive or vibratory compaction of uniform, medium-fine sand (more than 60 percent passing a No. 40 sieve). Inconsistent tensioning of the geosynthetic reinforcement.

Localized over compaction.

Backfill saturated by heavy rain or improper grading of backfill after each day’s operations.

6. Panels do not fit properly in their intended locations.

Panels are not level.  Differential settlement (see Cause 1).

Panel cast beyond tolerances.

Failure to use spacer bar.

7. Large variations in movement of adjacent panels.

Backfill material not uniform.

Backfill compaction not uniform.

Inconsistent setting of facing panels.

Documentation Requirements – 840 MSE Walls

1.        Did the panels arrive with a TE-24?

2.        Were the panels rejected or repaired as per the specifications?

3.        Was the select granular material approved?

4.        If the wall was in a cut, were the sidewalls properly protected?

5.        Was the foundation properly prepared?

6.        Was the drainage properly constructed?

7.        Was the filter fabric properly placed?

8.        Was the foundation undercut properly constructed?

9.        Was the leveling pad placed as specified?

10.     Were the wall panels placed according to the plan and markings on the back of the panels?

11.     Was external bracing used for the first lift of panels?

12.     Were the horizontal and vertical tolerances met?

13.     Was the soil reinforcement placed perpendicular to the wall face?

14.     Was the SGB placed in 8-inch lifts?

15.     Was the backfill compacted to the specification requirements?

16.     Was the backfill within 3 feet of the wall compacted to the specification requirements?

17.     Did a manufacturer’s representative inspect the site during the wall construction?

18.     Did the soils consultant properly take the compaction tests?

19.     Was the coping and traffic barrier constructed properly?

20.     Were the pile sleeves constructed properly?

21.     Perform all the compaction tests according to S-1015  or SS-878.

22.     Document on the CA-EW-1,CA-EW-3, CA-EW-8, CA-EW-12, and CA-D-3.  Do not duplicate the information on all forms unless necessary.

850 Cement Treated Free Draining Base

Materials (850.02)

The cement treated free draining base (CTFDB) is to be a mixture of coarse aggregate, Portland cement and water.

Cement used must be Type 1A (701.01) or Type I (701.04) conforming to ASTM C 150.

The coarse aggregate used can be either No. 57 or No. 67 size per Table 703.01-1.

Proportioning, Mixing, and Transporting (850.03)

The Contractor must proportion, mix, and transport the CTFDB according to Item 499.

The mix is to be prepared as follows:

The minimum cement content must be 250 pounds per cubic yard (148 kg/m³) when using No. 57 size coarse aggregate. The minimum cement content must be 220 pounds per cubic yard (130 kg/m³) when using No. 67 size coarse aggregate.

The water to cement ratio is 0.36.

A water-reducing admixture meeting 705.12 can be used.

Verification of Design (850.04)

The Contractor must submit a mix design for the proposed CTFDB 30 days prior to the start of production.  This mix design must describe the proposed aggregate size, the cement content, and the water content by weight.  A private laboratory must perform tests on the proposed mix to verify the yield of the mix design. 

Inspection should include random sampling of the CTFDB material delivered to the project to ensure conformance to the mix design.  The unit weight of the mix must be determined and the yield checked.

Equipment (850.05)

The Contractor must provide all equipment necessary to mix, transport, place, compact, and finish the CTFDB.  Equipment must be approved before the work begins.

A spreader must be used if the width being placed is more than 12 feet (3.6 m) or the total area of any given width exceeds 5,000 square yards (4,000 m²) of area.  The spreader could be a concrete spreader or an asphalt paving machine.

Initial compaction may be done by using a steel wheel roller, a modified slip-form paving machine with vibratory plates, or high-density screed pavers.  Compaction must not crush aggregate particles or cause segregation.  Final compaction must be done with steel wheel rollers weighing 6 to 10 tons (5 to 9 metric tons).  If vibratory rollers are used, do not use them in vibratory mode.

Figure 850.A – Spreading with an Asphalt Paving Machine

Figure 850.B – Spreading CTFDB with a Concrete Spreader

Placing and Spreading (850.06)

The Contractor must thoroughly moisten the base if there is no prime coat specified in the Contract prior to placing the CTFDB.  Workers must not contaminate the CTFDB by walking through it with mud or other foreign material on their work shoes.

The CTFDB must be spread in a smooth, uniform layer prior to compacting it.

Inspection should include sampling the CTFDB mixture and testing for in-place gradation after it is spread and before compaction.  This testing is to be done in accordance with Supplement 1090.

Limitations on Placing Operations (850.07)

Minimum temperature is required to be 35 ºF (2 ºC) and rising.

The material is not placed on frozen material or on rain softened subgrade or base.

Figure 850.C – Vibrating Plate behind Concrete Spreader

Figure 850.D – Steel Wheel Roller Compact the CTFDB

Compaction and Shaping (850.08)

The CTFDB is to be shaped to produce a uniform density and cross-section.  Compaction must not cause crushing of the aggregate particles.

The Contractor must make a minimum of two passes over any given area with the required steel wheel rollers.

Construction joints between each day’s work must be made by cutting transversely across the hardened CTFDB with diamond saws or the Contractor is permitted to use forms to form the construction joints.

Figure 850.E – Curing CTFDB with 6 mil White Opaque Polyethylene Sheeting

Curing (850.09)

Curing of CTFDB is to be done by placing 6 mil (150 μm) white opaque polyethylene sheets over the completed work.  These coverings must be left in place for a minimum of 3 days.  A cure day is defined as 24 consecutive hours of time in which the temperature is above 40 ºF (5 ºC).  Add a cure day for each day the temperature falls below 40 ºF (5 ºC).  Do not allow the use of liquid concrete curing membranes for curing.

Protection of the Underdrains (850.10)

Care must be exercised by the Contractor so as not to damage any installed underdrains during placing or compacting of the CTFDB.  The Contractor must ensure positive connection between the underdrain backfill and the CTFDB at all times during construction.

Protection of the Cement Treated Free Draining Base (850.11)

The Contractor is permitted to haul materials or operate equipment on completed CTFDB, provided there is no significant displacement, breakup, or contamination.  If any of this occurs, the Contractor must stop using the completed CTFDB for such purposes until the Contractor can demonstrate to the Department that it will not happen again in the future.  Any damage to the CTFDB must be corrected by the Contractor at no cost to the state.

The Contractor must protect the completed CTFDB from contamination of fine material at all times. 

The Contractor must use track mounted asphalt paving machines for placing the first lift of asphalt concrete on top of completed CTFDB.  This first course must cure at least over-night before placing succeeding lifts of asphalt concrete.

Thickness Tolerances (850.12)

The compacted depth of the CTFDB is to be 4 inches (100 mm) with a tolerance of ± 1/2 inch (13 mm).  Depth checks must be made every 2,000 square yards (1650 m²).  Areas found to be out of this tolerance must be removed and replaced at no cost to the Department and retested for proper thickness.

Surface Tolerance (850.13)

The CTFDB must be constructed to the proper elevation and have the plan specified cross-slope. Checks should be made periodically to verify these parameters.  The surface tolerance of the finished surface must not vary more than 1/2 inch from a 10-foot (13 mm from a 3 m) straightedge.  Any irregularities exceeding this amount must be corrected by the Contractor.

Exposure to the Elements (850.14)

The Contractor is required to place the next pavement layer on top of the CTFDB within 40 days from the end of the curing period.  In addition, the Contractor must plan the work so that the CTFDB is completely covered with the next pavement layer and have the underdrain system in place and functioning by the end of the construction season in any calendar year.

Method of Measurement and Basis of Payment (850.15 & 850.16)

The project will measure and calculate the area in square yards (square meters) based on the typical sections shown on the plans.  Payment will be made at the contract bid price for work that is accepted in place.

Documentation Requirements - 850 Cement Treated Free Draining Base

1.        Materials.

2.        Verify design.

3.        Proportioning and mixing as per 850.03.

4.        Prime base or sprinkle base with water.

5.        Temperature must be above 35 °F (1.6 °C).

6.        Use a spreader if project quantity exceeds 5,000 square yards (4,000 square meters).

7.        Compact and cure in accordance with 850.08 and 850.09.

8.        Check segregation and thickness.

9.        Curing and protection.

10.     Pay and measure according to 850.15 and 850.16.

11.     Document on CA-EW-12, CA-D-1, and CA-D-2. Do not duplicate the information on these forms unless necessary.

851 Asphalt Treated Free Draining Base

Description (851.01)

This work consists of constructing asphalt treated free draining base (ATFDB) course, mixed in a central plant, and spread and compacted on a prepared surface.  The (ATFDB) drainage layer is immediately beneath the pavement and is made of graded aggregate, asphalt-treated, permeable material. Construction of this drainage layer will serve satisfactorily as drains and structural support for the surfacing materials.

The requirements of Item 401 apply, except as modified by Supplemental Specification 851.

Materials & Composition (851.02 & 851.03)

The aggregate gradation should conform to Table 703.01-1 and 703.04 with the exceptions detailed in 851.02, and the binder should be PG 64-22 and conform to the requirements of 702.01.  The Contractor is not allowed to use reclaimed asphalt concrete pavement in the mix.

The binder amount should be 1.5 to 3.5 percent by weight of the mix with the aggregate.  Ensure that the aggregate does not show excess drainage at 250 °F (120 °C) and is coated with a shiny, black coating of asphalt binder. 

Brown or dull mix appearance is not acceptable and is a sign of excess aggregate absorption of the asphalt binder or low asphalt binder content.  Minor bare aggregate exposure is acceptable.

Design Verification (851.04)

A minimum of 3 weeks before the production of the ATFDB, the Contractor should submit a computed blend of aggregate and asphalt binder using standard JMF submittal forms and production temperature range to the Laboratory for initial design verification.  The Contractor should notify the Laboratory before the delivery of any material.

Final design verification is subject to field verification and actual performance.  Field verification may include additional testing by the Laboratory.

Rollers (851.06)

The Contractor should use only tandem steel wheel rollers weighing 6 to 10 tons (5.5 to 9 metric tons) for compaction.

Weather Limitations (851.07)

The Contractor should spread the ATFDB mix only when the atmospheric temperature is above 45 °F (7 °C).

Cease all operations if rain occurs during placement of the ATFDB or when rain is imminent.  Do not spread on frozen material.

Spreading and Compacting (851.08)

The Contractor should spread the ATFDB material in a method that produces a smooth, uniform layer before compacting.  Cease all operations when signs of degradation, segregation, or contamination are evident.  Communicate with the Contractor and the material monitor to resolve the problem before resuming placement.

The Contractor should sufficiently compact the ATFDB by compacting the layer at least two roller passes over any given point, unless otherwise directed by the Engineer for more passes.  Do not over compact the ATFDB to the extent where the aggregate particles are crushed or broken.  Complete rolling before the mix temperature has dropped to less than 100 °F (38 °C).

Do not cool ATFDB with water.

Form transverse construction joints by cutting back into the completed work to form a vertical face.

If significant breakup of the ATFDB occurs at or near the outer portion of a lift during the compaction operation, provide lateral support using forms or other methods approved by the Engineer at no additional cost to the Department.  Do not contaminate the ATFDB with this lateral support.

When the ATFDB is placed in areas inaccessible to rollers, compact the pavement using a method approved by the Engineer.

After compaction is complete, do not place the next layer of pavement on the ATFDB until the next day.

Thickness Tolerances (851.09)

The compacted thickness of the ATFDB layer should be 4 inches (100 mm).  Ensure the placed ATFDB conforms to the specified thickness by randomly checking the thickness during construction.  The district could run a dry-rodded unit weight to establish a conversion factor that could be used to establish the required placement rate as per 401.  Also, since the loose layer does not compact much, a prod is frequently used to check the layer thickness. Remove all sections found to be ± 1/2 inch (± 13 mm) from the specified thickness and replace them with ATFDB at no additional expense to the Department.

Surface Tolerance (851.10)

Ensure that the finished surface is uniform and varies no more than 1/2 inch (13 mm) from a 10-foot (3 m) straightedge applied to the surface, parallel to the centerline of the pavement.  Remove any section found to be out of tolerance and replace it with ATFDB within the specified tolerance at no additional expense to the Department.

Quality Control and Acceptance (851.11)

The quality control and acceptance requirements of Item 403 apply, except as detailed in 851.11.  Project administrators should check with the district lab to ensure material conformance to the specifications.

The ATFDB should be coated with shiny, black coating of asphalt binder and not be brown or dull in appearance.  Minor inconsistent bare aggregate exposure is acceptable.  If the delivered mix is brown or dull in appearance, immediately inform the district lab and the Contractor to adjust the asphalt binder content.

Underdrains (851.12)

Ensure that the underdrain system is functional before placing the ATFDB.  Do not allow construction equipment to crush the underdrain pipe or system as a result of the placement or compaction of the ATFDB.  Ensure a positive connection between the underdrain system and the ATFDB, regardless of the sequence of operations in the contract documents.

Protection of the ATFDB (851.13)

The ATFDB is not designed to carry construction traffic.  The Engineer will allow hauling units and other construction vehicles to operate on the ATFDB, provided no significant displacement, breakup, or contamination occurs.  If the Engineer determines significant displacement, breakup, or contamination of the ATFDB is occurring, the Contractor shall stop operating hauling units and construction vehicles on the ATFDB.  The Contractor should repair or replace all damage to the ATFDB, subbase, subgrade, or underdrains caused by the hauling units or construction vehicles at no additional expense to the Department.

The ATFDB layer should be protected from fine material contamination.  Adequate surface and subsurface drainage for the ATFDB, subbase, and subgrade should be provided at all times.

The Contractor may use a rubber tire paver if it does not damage the ATFDB, subbase, subgrade, or underdrains.  If damage occurs, cease paving and switch the rubber tire paver with a track mounted paver before restarting the paving.

When constructing asphalt concrete pavement on the ATFDB, allow the first course to cure overnight before placing the succeeding pavement courses.

Exposure to the Elements (851.14)

The ATFDB layer should be covered by constructing the pavement within 40 days and before the atmospheric temperature falls below 35 °F (2 °C) for any period of time

The Contractor should remove and replace all damage caused to the ATFDB, subbase, subgrade, or underdrains by the exposure to temperatures below 35 °F (2 °C) at no additional expense to the Department.

Method of Measurement and Basis of Payment (851.15 and 851.16)

The Department will measure the accepted quantities of asphalt treated free draining base by the number of square yards (square meters). The Department will measure the width as the width of the ATFDB shown on the typical sections of the plans and additional widening where called for, or otherwise directed in writing, by the Engineer.  The Department will measure the length horizontally along the centerline of each roadway or ramp.  Payment will be made at the Contract bid price for work that is accepted in place.

Documentation Requirements - 851 Asphalt Treated Free Draining Base

1.        State condition of base (e.g., primed 304, clean and dry concrete, etc.)

2.        Write location on tickets where material is placed.

3.        Mark on ticket the time unloaded.

4.        Obtain temperature of the mix at project site and place this information on ticket of load checked. This should be done a minimum of four times daily or any time temperature is in question.

5.        State kind of rolling equipment. 

6.        Calculate and document the required placement rate (tons/station).

7.        Document on form CA-FP-4 project documents compliance with Item 851, on Form CA-D-3A, and measurements on CA-D-1 and 2.

8.        Document lift thickness.

9.        Tickets should be totaled with initialed and dated tape attached.

S-1015 Compaction Testing of Unbound Materials

General

Supplement 1015 details the compaction testing requirements for all ODOT projects.  ODOT technicians and testing personnel provided by the Contractor must follow the testing procedures described in S-1015.

When the Contractor provides the compaction testing, one of two possible supplemental specifications will be included in the Contract Documents.  The two supplemental specifications, SS-878 and SS-879, are similar, but SS-878 pays for the inspection and testing as a lump sum pay item, while SS-879 pays for the work by providing incentive pay to the Contractor.

There is one compaction and inspection table for S-1015, SS-878, and SS-879.  Table 1015.10-1 in Section 1015.10 includes columns for the materials, test or method, maximum lot size, and minimum number of tests.   The same number and type of inspections and compaction tests are taken regardless of which specification is used in the Contract. 

SS-878 Inspection and Compaction Testing of Unbound Materials

This item is used when construction personnel are limited and the District wants full-time inspection and compaction testing for the work.

SS-878 pays for the inspection and compaction testing as a lump sum pay item and covers Items 203, 204, 205, 206, 304, 307, 411, 503, 611, and MSE wall select granular backfill.

The major aspects of the specification are as follows:

1.        The Contractor is to supply full-time qualified inspection and compaction testing for all specified items.

2.        The compaction tests are performed according to S-1015.

3.        The documentation is performed on department forms.

4.        The documentation is presented to the Engineer daily and a summary report is required every 2 weeks.

5.        There are qualifications requirements for the inspection and compaction personnel.

6.        The Department will perform QA compaction tests.

7.        There is a lump sum payment for this work.

SS-879 QC/QA for Embankment Construction

The major aspects of the specification are as detailed below:

1.        Several of the sections in this specification refer to SS-878, because they are basically the same work with the payment mechanism being different.

2.        The Contractor supplies full-time qualified inspection and compaction testing for Items 203 and 204.

3.        The compaction tests are performed according to S-1015.

4.        The documentation is performed on department forms.

5.        There are qualification requirements for the inspection and compaction personnel.

6.        The Department will perform QA compaction tests.

This supplemental specification is very similar to SS-878, except there is a pay adjustment ± 4 percent to the amount bid for Items 203 and 204.  This specification allows for more Contractor responsibility for the work with an appropriate incentive.  It also allows the Department to reduce the amount of full-time inspection of the work.

Metrication and Rounding

Most of the tables, forms, graphs, curves, and tests in this section are in English and Metric units.  The units are labeled with the English units first and the metric units in parenthesis (i.e., English [metric]). 

Weight measurements should be measured to the nearest 0.01 of a pound or kilogram.  All calculations are normally recorded to the nearest 0.1 or 4 significant digits.  Normally the final compaction results are recorded to the nearest percentage of compaction and acceptance is based on rounding.  The rounding of 97.6 percent compaction is rounded up to 98 percent compaction, while 97.5 is rounded down to 97 percent compaction.  The rounding of other calculations and measurements are done in a similar manner.

Importance of Proper Inspection and Compaction Testing

The Contractor constructs the embankment.  As the representatives of the Department, Inspectors and Engineers observe the work to ensure compliance with the specifications. As the Department inspects the work, instructions are given to the Contractor, such as the material is too dry, too wet, or does not have enough stability or density.

What happens when an embankment fails and we determine that one of the following has occurred?

1.        The instructions to the Contractor were in error.

2.        Compaction tests were performed incorrectly.

3.        Compaction forms were incomplete.

4.        No inspection or part-time inspection occurred during the construction.

All of the above reasons are arguments that are issues during a claim.  Valid or not, these are reasons that will be debated when responsibility is discussed.  Considerable financial loss to the Department could result during these negotiations or in court because of any one of the above reasons.

Our goal with this section is to minimize the Department liability in the above claim situations.

Compaction testing is an important evaluation tool that measures the quality of the earthwork construction work.  Therefore, this entire section is dedicated to obtaining correct and accurate results.

Compaction of Soils

Moisture-Density Relationship

In order to understand compaction testing, the project personnel must first understand the moisture-density relationship and some of the variables associated with this relationship.

A relationship exists between the density of a soil and the moisture content of a soil as the moisture content is varied while the compactive effort remains constant.  A standard force is used in the test that closely approximates the densities that can be readily obtained in the field with footed drum rollers and other types of common compaction equipment.  The greatest dry density obtained in the test is termed, “maximum dry density,” and the corresponding moisture content is termed, “optimum moisture content.” This moisture-density relationship is shown in Figure 1015.01.A.

Figure 1015.01.A - Typical Moisture-Density Curve

The test used by the Department to determine the moisture-density relations of soil is AASHTO T-99, Method C, called the Standard Proctor test.  The basic principle involved in the moisture-density relationship is an important tool when evaluating a soil.

For a given force of compaction and given moisture content, a soil will have a corresponding density.  Additionally, there is a particular moisture content for each soil at which a given compaction requirement can be obtained with less compaction effort than at any other moisture content.  This moisture content is the optimum moisture content.

Structural properties of a soil vary with moisture content and density.  For example, a clay soil at a low density will have very high load-supporting strength when dry, but when it is saturated at this same density, it will have a very low load-supporting strength.  Hence, when the structural properties of the soil are being determined, its moisture content and density must be defined and controlled to permit accurate evaluation of the soil in that particular condition.

Refer to Figure 1015.01.A to understand the influence of moisture on the compaction of soils.  At point 3, the soil is compacted at a moisture content where the compactive effort cannot overcome the friction or resistance of the soil to achieve a maximum dry density.  As the water content increases, the particles develop larger and larger water films around them, which tend to lubricate the particles and make them easier to move about and reorient into a denser configuration.

As the moisture content is increased, we eventually reach point 1, where the density does not increase any further with water content.  At point 1, the soil has just enough moisture to overcome most of the friction and not too much to have excess pore pressure to displace the soil. 

As the moisture is increased from point 1 to 2, the density decreases as the water starts to displace and replace soil particles because of the excess pore pressure.

Making a Moisture-Density Curve

This section outlines procedures to determine the optimum moisture content, maximum wet density, and maximum dry density of a soil, shale, or granular materials.  This procedure is not normally performed in the field.  It is generally only needed to determine the optimum moisture content for Test Section Method A.

The procedures outlined in this section follow AASHTO T-99, Method C with some minor modifications.

Equipment

The equipment needed to make a moisture-density curve is as follows:

1.        Proctor mold.

a.        Cylindrical brass or cadmium-plated steel mold, approximately 4 inches (102 mm) in diameter, 4-1/2 inches (114 mm) in height, and has a capacity of 1/30 ft³ (9.43 × 10-4 m³). 

b.        The cylinder is mounted on a removable base plate and fitted with a detachable collar approximately 2-1/2 inches (63 mm) in height.

2.        Proctor hammer.

a.        Brass or cadmium-plated steel sleeve rammer which has:

                                                               i.      A striking face 2 inches (50 mm) in diameter.

                                                              ii.      A weight of 5.5 lbs (2.5 kg).

                                                            iii.      Equipped to control the height of drop to 12 inches (305 mm).

3.        Steel straightedge 12 inches (305 mm) long.

4.        Scale of 25 lb (12 kg) capacity sensitive to 0.01 lbs (1 gram).

5.        A 3/4-inch (19 mm) sieve.

6.        Oil or gas stove or portable oven unless dried by other methods.

7.        Baking pans, approximately 12 inches × 8-1/2 inches × 2-1/2 inches (300 mm × 200 mm × 63 mm).

8.        Masonry trowel and putty knife.

9.        If the test is performed in the field, use a large concrete block or piece of concrete beam.

a.        Minimum size is a 12-inch × 6-inch (300 mm × 150 mm) cinder block.

b.        Or a 4-inch × 12-inch (100 mm × 305 mm) solid concrete block.

c.        Do not use wood or asphalt.

Procedure

Use the form CA-EW-4 (shown in Figure 1015.01.B) to record test data as obtained by the procedure outlined in this section.  This form shows an example of recorded test data.  Each column is lettered and used throughout this section to facilitate referring to the explanation.

1.        Secure a representative sample of soil of about 40 lbs (20 kg).

2.        Pass the sample through a 3/4-inch (19 mm) sieve.

3.        Wet or dry the sample.

a.        Change the moisture content to 4 to 6 percent below optimum.

b.        See 1015.01.F, Estimating Optimum Moisture Content, in this section for more information.

4.        Make a Proctor.

a.        Make a specimen by compacting the prepared soil in the Proctor mold.

                                                               i.      Make three equal layers to give a total compacted depth of about 5 inches (130 mm).

b.        Compact each layer by applying 25 uniformly distributed drops from the 5.5 lb. (2.5 kg) rammer dropping from a height of 12 inches (305 mm) above the elevation of the soil.

c.        See Figure 1015.01.D for recommended loose and compacted soil lifts.

                                                               i.      Loose lifts will change depending on the consistency of the soil. 

d.        Ensure that the cylinder is resting on a uniformly rigid foundation during the compaction. 

                                                               i.      Use a large concrete block or piece of concrete beam.

                                                              ii.      The minimum size is a 12-inch × 6-inch (300 × 150 mm) cinder block.

                                                            iii.      Or a 4-inch × 12-inch (100 × 305 mm) solid concrete block. 

                                                            iv.      Do not use wood or asphalt.

5.        Remove the extension collar.

a.        The soil should be less than 1/2 inch (13 mm) above the mold.

b.        If the soil is lower than the top of the mold, repeat the test.

c.        Carefully trim the compacted soil even with the top of the mold using the straightedge.

d.        Add fine material to fill any voids if necessary.

                                                               i.      Use the fines from the tested soil.

6.        Weigh the cylinder and sample.  Input this information in Column A

a.        Calculate the density of the specimen by subtracting the weight of the mold from the weight of the specimen and mold, and multiply the difference by 30 for English units and 1,060 for metric units.

                                                               i.      Column A – 9.81 lbs = Column B

13.34 - 9.81 = 3.53

9.81 is the weight of the mold

                                                              ii.      Column B × 30 = Column C

3.53 × 30 = 105.9

                                                            iii.      Column C is the wet density of the Proctor soil.

7.        Remove the material from the mold and slice vertically through the center. 

a.        Take a representative sample of the material from one of the cut faces and determine the moisture content by a method outlined in Section 1015.02.H, Alternate Tests for Moisture.

b.        If the only available scales are those included in the compaction control kit, a 1 lb (0.5 kg) sample is required for the moisture determination.  However, if a more sensitive scale is available, use a 0.22 lb (100 gram) sample.  The smaller sample will dry faster.

                                                               i.      The scales need to be leveled with a carpenter’s level.  Put the scale on a piece of flat plywood then level the board.  You may elect to level the weighting plate.

                                                              ii.      The older scales must also be balanced once it is leveled.  The weighting mechanism should float between the top and bottom bar.  If it does not, sand or pebbles can be added to the lever arm to make it balance.

c.        Calculate the dry weight and the moisture content as follows:

                                                               i.      Column D…Weight of the dish and the wet soil.
96.2

                                                              ii.      Column E…. Weight of the dish and soil after drying.
93.4

                                                            iii.      Column F…Column D - E = Weight of Water
96.2 - 93.4 = 2.8

                                                            iv.      Column H…Column E - G= Dry Soil Weight
93.4 – 40.0 = 53.4

                                                              v.      Column I…F/H × 100 = Percent Moisture
Water Content = Weight of Water /Dry Weight
(2.8/53.4) × 100 = 5.2%

                                                            vi.      Column J…C/(1+ I) = Dry Weight of the Soil
Dry Weight =Wet Weight/ (1 + Wc )
In the Example:

WD= 105.9/(1+0.052) = 100.5

8.        Thoroughly break up the remainder of the material until inspection shows that it will pass a 3/4-inch (19 mm) sieve.  It is not necessary to pass all of the material through the sieve.

9.        Add water in sufficient amount to increase the moisture content of the soil sample by 2 or 3 percent, and repeat the procedure outlined in D through H.

10.     Repeat D through H, each time adding water until you obtain at least 4 readings for the wet weight, dry weight, and moisture content. 

a.        Continue the process until a minimum of two points are plotted on the wet and dry side of the dry weight curve and there is a decrease in the wet weight.

11.     Use Figure 1015.01.C) as an example and plot test data as follows:

a.        Plot wet weight, Column C, versus moisture content, Column I, of the successive tests on linear graph paper. 

                                                               i.      Draw a smooth curve between the successive points.

                                                              ii.      The peak of this curve is the maximum wet weight of the material being tested.

                                                            iii.      This maximum weight is not used for compaction acceptance.

b.        Plot dry density, Column J, versus moisture content, Column I, of the successive tests on linear graph paper. 

                                                               i.      Draw a smooth curve between the successive points.

                                                              ii.      The peak of this curve is the maximum dry density of the soil.

                                                            iii.      The moisture content at this point is the optimum moisture content.

                                                            iv.      This curve can be used for compaction acceptance.

Figure 1015.01.C (1015.01.C-M) shows curves plotted from the test data in Figure 1015.01.B.

Figure 1015.01.B – Moisture-Density Calculation Form

Figure 1015.01.C – Moisture-Density Curve Plot

Figure 1015.01.D - Loose and Compacted Lifts for the Proctor Test

Ohio Typical Density Curves

The Ohio Typical Density Curves are a set of soil curves originally developed in the 1930’s and 1940’s to represent all the soils in Ohio.  They were developed in the laboratory using the standard Proctor test.  They started with an original set of nine curves that represented over 1,000 samples.  Additional curves were added that represent over 10,000 lab samples.  These curves are plotted in Figure 1015.01.E.  These curves are still used today to represent all the soils in Ohio.  Using these curves minimizes the need to make moisture-density curves for each type of soil encountered in the field.

Figure 1015.01.E - Ohio Typical Density Curves

A one-point Proctor test is used to choose the curve that represents the soil under consideration.  The procedure is similar to the AASHTO T 272 test and is detailed in Supplement 1015.06.C.1.

Usefulness of the Moisture-Density & the Ohio Typical Density Curves

By examining the moisture-density or the Ohio typical density curves, one can gain general information on the load-carrying capacity and other information about the soil properties.

The optimum moisture content and maximum dry density of the moisture-density relationship are comparative factors.  A high maximum dry density ranges from 125 to 140 lbs/ft³ (2,000 to 2,250 kg/m³) dry density.  A low maximum dry density ranges from 100 to 85 lbs/ft³ (1,600 to 1,350 kg/m³) dry density.  A low optimum moisture content coincides with a high maximum dry density and will be on the order of 7 percent.  A high optimum moisture content coincides with a low maximum dry density and may be on the order of 25 percent.

The maximum dry density of a soil gives approximate information on its gradation and soil type.  The approximate range of the maximum dry density for particular soils are as follows:

Soil Type

Typical Maximum Dry Density
Pounds per Cubic Feet (Kilograms per Cubic Meter)

A-1 & A-2

120 to 135 (1922 to 2163)  Granular Soils

A-2

120 to 130 (1922 to 2082)  Granular Soils

A-3

110-to 120 (1762 to 1922)  Granular Soils

A-4

105 to 120 (1682 to 1922)  Silty Soils

A-6 & A-7

90 to 110 (1442 to 1762)   Clayey Soils

The optimum moisture content gives approximate information on the clay and silt content of the soil.  The shape of the moisture-density curve varies from a sharply peaked parabolic curve to a flat one or to one sloping irregularly downward as the moisture content increases. This shape gives additional valuable information showing the influence of moisture on the load-supporting value of the soil.  For example, a flat moisture-density curve indicates a soil that will have about the same load-supporting strength over a wide range in moisture contents, while a moisture-density curve with a sharp peak indicates a soil that is sensitive to changes in moisture content.

Variations in the Moisture-Density Relationship

To truly understand the moisture and density relationship as it relates to soil compaction, the project personnel should understand what items affect this relationship.  This section briefly addresses these issues.

This moisture-density relationship is affected by, but not limited to, the following conditions:

1.        A change in the laboratory compactive effort or a field compactive effort that is different from the laboratory testing compactive effort.

2.        A temperature of the compacted soil that is near or below freezing temperature.

3.        Coarse aggregate that is added or subtracted from the soil.

Changing the Compactive Effort

The AASHTO T 99 Proctor test, used to make the Department’s moisture-density curve, was originally made to simulate field compaction conditions.  It uses a standard compactive effort that allows us to evaluate and compare the compaction and densities of different soils.  What happens to this moisture-density relationship as you increase or decrease this compactive effort?

In Figure 1015.01.F, the compactive effort may be increased or decreased to change the maximum density as much as 10 to 15 lbs/ft³ (160 to 240 kg/m³).  As the compactive effort increases, the curve shifts to the left and up along the same line of optimum.  If the compactive effort is lowered, the compaction curve shifts to the right and down.

Figure 1015.01.F - Changing the Compactive Effort

Temperature Effects on Soil

If a soil is compacted at low temperatures, the maximum density cannot be achieved in the field.  The specifications do not allow soil to be compacted that is frozen. Figure 1015.01.G shows why this is the case.  The maximum density can change as much as 10 lbs/ft³ (160 kg/m³) for soils compacted at temperature differences of 40 ºF (20 ºC).  However, there may not be any difference in maximum density.  Temperatures affect some soils but not others.  There is not a formula that takes this temperature difference into consideration.

Figure 1015.01.G - Temperature Effects on the M-D Curve

Compaction procedures must be altered to check for this difference.  Use the following procedure when the Contractor is compacting the soil at temperatures lower than 45º F (7º C) or when the site conditions warrant:

1.        Take the normal Proctor test during the compaction testing.  Choose the curve associated with this compaction test.

2.        Take enough soil from the same hole to make another Proctor later.  After the soil is warmed to approximately 70 ºF (21 ºC) make an additional Proctor.  Pick an additional curve using the wet weight of the second Proctor and moisture content from a drying method.

3.        Compare the two results and use the higher curve if there is a difference.  Use this procedure at any time the material is suspect in the field.

Coarse Aggregate Problem

The moisture-density relationship is very good for soils passing the 3/4-inch (19 mm) sieve as it relates to the field compaction of soils.  There are problems when this relationship is extrapolated to soils larger than the 3/4-inch (19 mm) sieve material or for granular soils.  Corrections must be made to account for these materials.  In certain circumstances, field densities do not correspond to the laboratory results.  These will be pointed out in later sections.

Figure 1015.01.H details a plot of adding or subtracting coarse aggregate to a soil and the resulting change in the moisture-density curves.

Figure 1015.01.H - Coarse Aggregate Effects on Soil M-D Curve

As you add gravel or 3/4-inch (19 mm) material to the soil, the optimum moisture content shifts to the left and the maximum density increases.  The average increase in density is approximately 1 percent per 10 percent of material retained on the 3/4-inch (19 mm) sieve.  This effect is taken care of on the CA-EW-6 Compaction Form and is fully explained in Section 1015.03 of this manual.

If you sieve the material through the 3/4-inch sieve, remove 20 percent coarse aggregate, and do not consider this, you could easily be one or two curves lower than intended.

Use the correction on the CA-EW-6 Compaction Form where more than 10 percent of the material is retained on the 3/4-inch (19 mm) sieve.  This correction usually increases the maximum dry density and makes an optimum moisture content correction.

Importance of Temperature and Coarse Aggregate Corrections

The accuracy of all compaction testing is important; however, the importance of making temperature and coarse aggregate corrections in compaction testing are less obvious to the project personnel.  Without these corrections, the compaction testing could easily be off by more than 2 lbs/ft³ (32 kg/m³) without the project personnel being aware of a problem.

If the compaction testing is off by 2 lbs/ft3 (32 kg/m³), or approximately one Ohio Typical Density Curve, this may result in a loss of 15 percent of the soil strength.  If the testing is off by two curves, the potential loss could be 30 percent, and so on.  The strength may not be apparent in construction, but in the long-term, it may have devastating effects on the performance of the embankment.

Estimating Optimum Moisture Content

Soil Boring Interpretation Method

All cohesive soils are compacted at water contents less than the plastic limit of the material.  For A-7-6 soils, the optimum moisture content is around the plastic limit minus 3.  For A-4 and A-6 soils, the optimum is around the plastic limit minus 5.  The optimum moisture content of granular materials ranges between 5 and 10 and for non-plastic silts is around 11.

You can obtain an estimate of the material’s consistency by using the above information and looking at the soil’s water content from the soil borings before the work begins.  Keep in mind, the water content on the soil borings is the water content at the time the borings were drilled.  They should be considered an estimate of the present field conditions.

You can approximate the optimum moisture content of a material by the feel of the material in the field using one of the following methods.

Hand Squeeze Method

Take a sample of the material in question in your hand.

Squeeze the material together and let go.

Consult the following table:

If the material…

Then material is…

Falls apart in small pieces

Dry of optimum

Stays together

At or above optimum

Breaks into two or three large pieces

At optimum

Stays together and there is excess water on hands

Above optimum

Ball Method

Roll the material into a 1-inch ball.

Place it between your thumb and index finger and squeeze the material.

Consult the following table:

If the material…

Then material is…

Ball cannot be formed

Below optimum

Becomes oval

Above optimum

Breaks apart into uniform pieces

(Some clays will have larger pieces than silts)

At optimum

Spit Method

Spit on the material.

Consult the following table:

If the saliva…

Then material is…

Beads up

Above optimum

Slowly sinks in

At optimum

Use these methods as estimates; they do not replace compaction testing.  These estimates are different for each type of soil (clay, silt, granular).

Compaction Testing of Soils (1015.06)

General (1015.06.A)

Proper compaction at the proper moisture is the most effective and most economical way to improve the stability of soils.  Satisfactory performance of pavement and embankment depends on the good compaction of the embankment and subgrade materials.  Careful control is necessary to ensure compliance with the specification compaction requirements for embankments and subgrades.

The density test is the principal means by which the Engineer determines whether or not the specified compaction requirements have been met.  The number of tests to be made for a given quantity of embankment material placed is set by Supplement 1015.09.  The Engineer has broad powers to increase or decrease this testing depending on the field conditions.  The Engineer may use his or her judgment to make tests at locations where the information is most needed for proper control.

For example, consider an area of embankment under construction, where the soil and moisture conditions are uniform and ideal for good compaction, and where previous compaction tests have shown that the specification requirements are  consistently met under the same number of roller passes.  As long as inspections show that the uniform conditions of soil, moisture, lift thickness, and roller pass continue for this area, only occasional check tests for compaction are required.

Where relatively few tests are made because materials and conditions are uniform, document this by describing conditions on the Compaction Forms or other appropriate project records.  Avoiding a large number of tests in areas of uniform condition, where specified compaction is consistently obtained, allow the project personnel to concentrate their effort on other areas of the project where conditions are less uniform or suspect.

Tests must be made in areas where inspection indicates that the material is questionable, even if specified compaction is obtained.  Evidences of questionable compaction, which can be determined by inspection, include the following:

1.        Low number of roller passes to obtain compaction.

2.        Excessive deflection under heavy construction equipment.

3.        The use of lightweight rollers.

4.        Very wet or dry soil.

5.        Areas compacted without full-time inspection.

6.        Inconsistent materials, such as shale and rock mixtures, or recycled concrete mixed with soil.

The observation that a footed drum roller will “walk out” or “ride high” on a layer of hard, dry soil is not evidence of satisfactory compaction.  This soil may be stable when dry, but weak when wet.

Areas where compaction or moisture does not meet specification requirements must be corrected before the next lift of embankment is placed.

The Engineer must give specific directions to the Inspectors.  These directions must cover the Inspector’s responsibility and authority given to them by the Engineer.  This ensures that timely decisions are made in the field and that full compliance with the contract requirements is obtained on the project.

Control of compaction includes making moisture and density determinations for establishing whether the compaction meets the requirements prescribed in the specifications. 

A sufficient number of tests must be made to ensure that construction complies with the specifications.  The Nuclear Gauge Method is the only method used for compaction testing.  The sand-cone, rubber-balloon, and cylinder density tests have been eliminated.

Regardless of the method chosen, a one-point Proctor test is used to identify the curve that represents the soil in question for each compaction test, except for materials requiring a test section.

Equipment (1015.04)

1.        Equipment listed in Section 1015.03.

2.        A 3-inch (75 mm) or 4-inch (100 mm) post-hole auger.

3.        A container with a 4-1/2-inch (114 mm) hole cut in the bottom.

4.        Troxler 3440 Nuclear Gauge.

5.        25 to 50 lbs (12 to 23 kg) of dry, uniform, natural sand passing the No. 10 (2 mm) sieve.

6.        Form CA-EW-5, Nuclear Gauge Compaction Form, and Form CA-EW-6, Nuclear Gauge Compaction with an Aggregate Correction.

Preparation of Surface (1015.06.B.2)

Select a location for the density test that is representative of a rolled area of the embankment layer being constructed.  If loose, uncompacted material, similar to what results from sheepsfoot rolling, exists on the surface, remove the loose material to expose the compacted material underneath.  Carefully level the test area by any convenient means, such as a dozer, grader, hand shovel, straightedge, etc.

Compaction Testing of Soil Using a Nuclear Gauge (1015.06.B)

The Department uses nuclear equipment manufactured by Troxler Laboratories.  Presently the Department uses the 3440 series gauges.  The operator should have a Manual of Operation for the gauge.

There is no radiological danger for the operation of a nuclear gauge so long as the correct operating and safety rules are followed.  Each operator is issued a specific set of instructions governing safety when the gauge is assigned to him or her.   For more information about the safety requirements see the following link to the Nuclear Labs website:

www.dot.state.oh.us/Divisions/ConstructionMgt/Materials/Pages/Radiation-Safety.aspx

In addition, contact the Nuclear Lab at (614) 275-1375 for more information.

For nuclear measurement of density, gamma rays emitted into the soil from a gamma source are scattered by the electrons in the soil and lose energy in the process.  The number of scattered rays returned and counted in the gauge depends on the average length of the path of the ray between the detector and source.  The electron density increases proportionally with the density of the soil and causes greater scattering and energy loss.  Therefore, the chances that scattered gamma rays returning to the detector with sufficient energy to be counted become smaller with increased soil density, and the count rate drops.  In common soil types, a low gamma ray count indicates a high density, and a high count indicates a low density.

For nuclear measurements of moisture, the neutron energy absorption technique measures the moisture content of rock or soil materials.  The nuclear method for measuring the moisture content of soil and rock materials is based on the principle of measuring the slowing of neutrons emitted into the soil from a fast-neutron source.  The energy loss is much greater in neutron collisions with atoms of low atomic weight and is directly proportional to the number of atoms present in the soil.  The effect of such a collision changes a fast neutron to a slow neutron.  Hydrogen, which is the principal element of low atomic weight found in soils, is contained largely in the molecules of water in an inorganic soil.  The number of slow neutrons detected by the gauge, after an emission of fast neutrons from a radioactive source, is counted electronically in the gauge.  The count obtained by the gauge is proportional to the amount of water in the soil or rock.

Density and moisture determinations can be made in any of the following two positions relative to the material being tested:

1.        Backscatter - Source and detector in the gauge are resting on the surface of the material being tested.

2.        Direct Transmission - Source in the rod is extended below the gauge into the material being tested, and the detector in the gauge is on the surface of the material being tested.

Figure 1015.02.A - Nuclear Gauge Direct and Backscatter Positions

Moisture-Density Testing

Use Form CA-EW-5 or CA-EW-6 for moisture-density testing when using a nuclear gauge.  The following is a summary of the gauge operations when testing soils.  Consult the detailed explanation in the owner's manual of procedures.  The gauge is self-driven throughout the process.  The operator pushes a button and the gauge asks a question or gives an answer.

1.        Determine the standard count.

a.        Perform at least every week or when the test location changes.

b.        Put the gauge on the standard block with the handle opposite the metal plate.  See Figure 1015.02.B.

Figure 1015.02.B - Nuclear Gauge on the Standard Block

c.        Make sure the standard block is resting on material which weighs more than 100 lbs/ft³ (1600 kg/m3).

d.        Press the "ON" button on the gauge panel (see Figure 1015.02.C).

                                                               i.      Wait approximately 4 minutes for the gauge to warm-up.

                                                              ii.      The gauge may already be on prior to placing it on the block.

                                                            iii.      The gauge will beep when ready.

Figure 1015.02.C - Nuclear Gauge Keypad

                                                            iv.      Readout:

1.        Depth: safe position.

2.        Time: 1 minute (possibly a longer duration).

3.        Battery: volts.

e.        Press the standard button.

                                                               i.      Readout:

1.        Do you want to take a new standard?

2.        Press "YES."

3.        Is the gauge in the safe position?

4.        Press "YES."

                                                              ii.      Readout:

1.        Taking a standard count.

2.        Takes 240 seconds.

3.        Gauge will beep when complete.

                                                            iii.      Readout when standard count is complete:

1.        MS          XXXX                    X.X%P

2.        DS           XXXX                    X.X%P

3.        P-Pass, F-Fail

4.        If reading is within 1 percent for density or 2 percent for moisture, the standard passed.

f.         Record standard count on lines 4 and 7 on the CA-EW-5 and lines 1 and 2 on the CA-EW-6.

g.        Do you want to accept the new standard?

                                                               i.      Press "YES" if acceptable.

                                                              ii.      Readout:

1.        Ready.

2.        Depth.

3.        Volts.

4.        Ready to take the readings.

2.        Taking Nuclear Gauge Readings.

a.        Clear away all loose material or dried crust.

                                                               i.      Obtain a level area with sufficient size to accommodate the gauge.

                                                              ii.      Use the scraper plate to help smooth out the surface.

                                                            iii.      See Figure 1015.02.D.

Figure 1015.02.D - Scraper Plate and Use

b.        Use the native fines or fine sand to fill the voids to finish smoothing out the surface.

                                                               i.      The maximum void beneath the gauge should not exceed 1/8 inch (3 mm).

c.        Make a hole perpendicular to the prepared surface by using the pin (drill rod) provided by the manufacturer.

                                                               i.      Drive 2 inches (50 mm) further than the depth of the reading.

d.        Mark the outside of the scraper plate. 

e.        Remove the scraper plate and position the nuclear gauge on the prepared location.

                                                               i.      Raise the gauge up on one side and extend the rod out about 2 inches (50 mm).

                                                              ii.      Place the rod over the hole and extend the rod the rest of the way.

f.         Extend the rod to the required depth.  See Figure 1015.02.E.

Figure 1015.02.E - Positions of the Nuclear Gauge

                                                               i.      Backscatter Position is used for:

1.        Bases.

2.        Granular Materials.

3.        Materials requiring a test section.

                                                              ii.      8-inch (200 mm) depth used for embankment.

                                                            iii.      12-inch (300 mm) depth used for subgrade.

                                                            iv.      The gauge gives the depth.

                                                              v.      The deepest depth is the most accurate.

g.        Pull the gauge toward the detector end or away from handle to seat the gauge into position (see Figure 1015.02.A).

                                                               i.      Eliminates the air gap between the source rod and the hole.

h.        Press "START/ENTER."

i.         After one minute:

                                                               i.      Readout:

1.        DD = Dry Density = Line 6= 133.0 lbs/ft3

2.        WD = Wet Density = Line 5 =144.4 lbs/ft3

3.        % M = % moisture = Line 8 = 8.3%

j.         Record information on Lines 5, 6, and 8 of the CA-EW-5 Form and on lines 3, 4, and 5 on the CA-EW-6 form.

k.        See Figure 1015.02.F.

                                                               i.      DD = Dry Density = Line 6= 133.0 lbs/ft3

                                                              ii.      WD = Wet Density = Line 5 =144.4 lbs/ft3

                                                            iii.      % M =  % Moisture = Line 8 = 8.3%

Using the Ohio Typical Curves

Optimum moisture content and maximum dry density can be determined from the Proctor test results, nuclear gauge results, and the Ohio Typical Density Curves as described in Section 1015.01.C and 1015.01.D.  Use the Plotted Ohio Typical Density Curves for compaction testing, which are in S-1015.

Once the wet density and percent moisture is obtained from the Proctor test, it can be used to find the curve that represents the soil being tested.  Use nuclear method or drying method to determine percent moisture in lieu of the penetration resistance method; do not use the penetration resistance method.

Figure 1015.02.F - Completed CA-EW-5 Compaction Form

Selecting a Typical Curve Using the Nuclear Gauge Results

1.        Secure a representative soil sample of about 10 lbs (5 kg).

a.        Use the soil between the end of the probe and the back of the gauge (see Figure 1015.02.A).

2.        Sieve the material through a 3/4-inch (19 mm) sieve.

a.        Use Form CA-EW-5 if less than 10 percent of the soil is retained.

b.        Use Form CA-EW-6 if more than 10 percent of the soil retained.

c.        Use a Test Section Method if more than 25 percent is retained.

3.        Thoroughly mix the material passing the 3/4-inch (19 mm) sieve.

4.        Make a proctor using Section 1015.01.B.2 of this manual.

a.        Make a Proctor test for every compaction test (a soil cannot be correctly identified without this test).

b.        When weighing the Proctor mold and soil, the scales must be level and balanced.

                                                               i.      The scales need to be leveled with a carpenter’s level.  Put the scale on a piece of flat plywood and then level the board.  You may elect to level the weighting plate.

                                                              ii.      The older scales must be balanced once it is leveled.  The weighting mechanism should float between the top and bottom bar.  If it does not, then sand or pebbles can be added to the lever arm to make it balance.

5.        Record and calculate the proctor results on Lines 10 through 13 on the CA-EW-5 and lines 11-14 on the CA-EW-6.

a.        Use Figure 1015.02.F.

b.        Line 10 (14.01 lbs) – Line 11(9.24 lbs) = Line 12 (4.77 lbs)

c.        Line 12 (4.77 lbs) × 30 = Line 13 (143.1 lbs/ft3)

6.        Pick the Wet density Curve Using

a.        The Proctor wet density.

b.        Line 13 = 143.1lbs/ft3

c.        Moisture from gauge readings or by another drying method.

d.        Line 8= 8.3%

7.        Use the printed Ohio Typical Density or Project Curves (see Figure 1015.02.G).

a.        Draw a horizontal line through the wet density on the Ohio Typical Density Curves from the Proctor weight on Line 13, on the CA-EW-5, or Line 14, on the CA-EW-6 Form.

                                                               i.      Line 13 = 143.1 lbs/ft3

b.        Extend a vertical line from the percent moisture shown on Line 8 on the CA-EW-5 or Line 5 on the CA-EW-6 Form to intersect the horizontal line.

                                                               i.      Line 8 = 8.3%

Figure 1015.02.G - Example of Using the Ohio Typical Density Curves

c.        If the intersection falls on a curve, choose the curve.

d.        If the intersection falls between two curves, choose the next highest curve.

8.        Use the maximum dry weight and optimum moisture data in the upper right hand corner of Figure 1015.02.G from the curve that is chosen.

a.        In this example, curve “D” is the correct curve.

9.        After the curve is selected, record optimum moisture content on Line 14 and the maximum dry density on Line 15 of Form CA-EW. For the CA-EW-6, record the optimum moisture content on Line 15 and the maximum dry density on Line 18.

a.        Line 15 = Maximum Dry Density = 134.1 lbs/ft³

b.        Line 14 = Optimum Moisture Content = 8.5%

Calculating Compaction and Zero Air Voids

Use Figure 1015.02.F.

1.        Use line 16 to calculate the difference in moisture contents.

a.        Line 14 = 8.5 percent - Line 8 (8.3 percent) = - 0.2 percent  (below optimum)

2.        Use line 17 to calculate compaction.

a.        (Line 6/ Line 15) × 100 = (133.0 lbs/ft3/ 134.1 lbs/ft3) × 100 = 99.2 percent.

3.        Compare to the allowable in the specifications shown in Table 203.07-1.

Table 203.07-1 Embankment Compaction Requirements

Maximum Laboratory Dry Weight

(lb/ft³ )

Minimum Compaction (percent)

90 to 104.9

102

105 to 119.9

100

120 and more

98

a.        Since Line 15 = 134.1 lb/ft3 > 120 the minimum required compaction is 98 percent.

b.        Line 17 = 99.2 percent > 98 percent

c.        The test passes.

4.        If density and stability are achieved, then moisture passed.

a.        See Manual of Procedures Section 203.07.

5.        Check zero air voids.

a.        Use Figure 1015.01.02.H.

b.        Use line 6 = 133.0

                                                               i.      Get 9.5

c.        9.5 percent > Line 8 = 8.3 percent

d.        Good (Line 8 may be a maximum of 1 percent above the Figure 1015.02.H value).

Can calculate the percentage by using the formula in Figure 1015.02.H

                                                               i.      Where G = 2.67 and D = line 6

                                                              ii.      If you are good with math, then the formula is much easier to use than the graph.

6.        The check on the zero air voids is not required by S-1015, but it is a good check on the nuclear gauge readings.  The moisture obtained from the curve or graph is the maximum moisture that can exist in the soil being tested.  If the gauge moisture readings are larger than the ones obtained from the graph, then an error may exist in the test.

Figure 1015.02.H - Zero Air Voids Curve

Moisture Controls

Moisture Control of Soil Embankments during Construction

This section discusses moisture controls during construction, details some of the variables in the moisture controls, and discusses alternate methods used to verify or modify the moisture readings from the nuclear gauge.

Experience has shown that to obtain the specification density, the moisture content must be at or near optimum.  Some soils, particularly silty soils with low plasticity, may meet the moisture (± 3 percent from optimum) and the compaction requirements, but have unsatisfactory stability.

Some soils compact better and meet the density and stability requirements at minimum moisture of -3 or more below optimum.  The reason for limiting the moisture contents for soil embankment this way is to ensure stable embankments.

The Elasticity and Deformation of Soils is discussed in Section 203.02 and Moisture Controls are discussed in Section 203.07.A of this manual.

There is not a numerical moisture requirement in the specifications.  The Contractor must compact the material at a moisture content to obtain the density and stability of the material.  Moisture and compaction controls are necessary to secure the quality of embankments and subgrades that are essential for the long life and performance.

Alternate Tests for Moisture

The specifications do not numerically limit the moisture content of embankment or subgrade soils.  Moisture determinations must be made in the field to pick the required moisture-density curve and to control the Contractor’s compaction operations.  The following sections deal with various methods of determining moisture contents of soils.

For engineering purposes, the moisture of soil is expressed in percent of dry weight.

Percent Moisture =

Weight of water in soil

× 100

Weight of dry soil

Most of the time, the moisture of a soil should be obtained by using the nuclear gauge readings.  However, there are situations where drying methods can and should be used.  Moisture content is the most variable reading from the nuclear gauge.  There are varieties of chemicals in the soils that can minimize the moisture content reading reliability.  This is particularly true for recycled materials, such as fly ash, bottom ash, foundry sand, or asphalt.

Use the moisture estimating principles detailed in Section 203.02 Estimating Optimum Moisture Content.  This section guides the determination of an alternate moisture measurement.

For each drying method, the soil to be tested should be a representative sample of at least 1 pound (0.5 kilograms).  The soil should be placed in a small, clean can or jar and covered with a tight lid at the construction site to prevent evaporation of moisture while moving to the location of the test.  The test should be conducted as soon as possible after taking the sample.  Location where sample is taken must be noted.

All the moisture tests should be checked against each other to ensure accuracy of the moisture testing.  To record the moisture results, use Figure 1015.01.B, Moisture-Density Calculation Form, and read the appropriate sections.

Oven-Drying Method

This method of determining moisture content is applicable to all types of soils.  The time required to dry the sample depends on the size and moisture content of the sample and the type of soil.

This method should be used for any recycled material.  This can be used to apply a moisture correction to the nuclear gauge readings when the material is uniform.  This is particularly true for fly ash.

Equipment

1.        Two-burner stove.  Either oil stove or a camp stove using white gasoline.

2.        “Boss 75” portable oven or equivalent.

a.        This oven measures approximately 20 inches (0.5 meters) high, 20 inches (0.5 meters) wide, and 13 inches (0.3 meters) deep.

b.        It sets on and is heated by the stove.

3.        Several baking pans approximately 12 inches × 8-1/2 inches × 2-1/2 inches (300 mm × 200 mm × 63 mm).

4.        Masonry trowel or putty knife.

5.        Can of fuel.  The can has tight stoppers and is painted red if used for gasoline.

6.        Scale of 25 pound (12 kilogram) capacity sensitive to 0.01 pound (1 gram).

7.        Piece of flat glass or pieces of bond paper with texture similar to the compaction forms.

Procedure

1.        Weigh the pan to the nearest 0.01 pound (1 gram).  Record the weight.

2.        Place approximately 1 pound (0.5 kilograms) of representative sample of wet soil in the pan on the scale.

a.        Record the combined weight.

3.        Break-up all lumps of soil with the putty knife or trowel and avoid any loss of the sample.

4.        Place the pan with the sample in the oven with the stove on.  Stir the soil every 3 to 5 minutes.

5.        After the soil has changed to a lighter color and appears to be dry, remove the soil sample from the oven and test to determine if it is completely dry by using one of the following methods:

a.        Lay a piece of bond paper approximately 2 inches × 3 inches (50 mm × 75 mm) on the sample. 

                                                               i.      If the paper curls immediately when laid on the sample, the soil contains moisture.

                                                              ii.      The paper used for this test must be bond of hard surface texture like the paper used for the compaction forms.

b.        Hold a piece of clean glass or a mirror in a horizontal position about 1 inch (25 mm) above the soil sample.

                                                               i.      If the glass steams up, this is an indication of further moisture in the sample. 

c.        Keep the glass away from the heat of the stove or direct rays of hot sun prior to the test since this test depends upon condensation of moisture in the hot air onto the cooler glass.

6.        If the test indicates further moisture in the sample, stir the sample and continue drying. 

a.        Test the soil every 3 to 5 minutes until the test indicates the soil is dry.

7.        Weigh the dried sample and pan to the nearest 0.01 pound (1 gram).  Record this weight.

8.        Subtract the weight of the pan from the weight of the pan and the dry sample to obtain the weight of the dried sample.

9.        Subtract the weight of the dried sample from the weight of the wet sample.  This is the weight of water in the original sample.

10.     Divide the weight of the water by the weight of the dried sample.  Multiply this result by 100.  This gives the percentage of moisture in the sample.  The equation is:

Percent Moisture =

Weight of wet soil – Weight of dry soil

× 100

Weight of dry soil

Open-Pan Drying Method

This method is quick, simple, and obtains accurate results for granular material.  This method should not be used for fine-grained soils (silts or clays) because the high temperatures may burn away the organic material if it happens to be present.  This method can be used for fine-grained soils where limited accuracy is satisfactory and approximate moisture results are acceptable.

This method should not be used for any recycled material.  It has been found to give lower moisture contents than is really in the material.  This is particularly true for fly ash.

Equipment

1.        Scale of 25 lbs (12 kg) capacity sensitive of 0.01 lbs (1 gram).

2.        Several baking pans approximately 12 inches × 8-1/2 inches × 2-1/2 inches (300 mm × 200 mm × 63 mm).

3.        Putty knife or other device for breaking up and stirring the soil.

4.        Two-burner stove burning white gasoline.

5.        Piece of flat glass or pieces of hard surface bond paper with texture similar to the compaction forms.

Procedure

Follow steps outlined in Section 1015.02.H.3, Oven-Drying Method, Steps A thru L, except place the pan directly over the burner instead of in the oven.

Precautions

The following cautions should be taken to avoid introducing errors into the test.

1.        Avoid overheating the soil.

a.        Use two pans, one inside the other, to avoid hot spots that may occur when a single pan is used.

2.        Avoid baking the soil.

a.        Baking can be prevented by testing the material with a paper or glass test at sufficiently close intervals, so that further heating can be discontinued after all the moisture has been evaporated.

3.        Ensure that no soil is lost during the test.

Alcohol-Burning Drying Method

This method is quick and simple.  The alcohol burns at a low enough temperature 286 ºF to 320 ºF (140 ºC to 160 ºC) so that it can be used with accuracy for most soil types. 

This method should be done outside or in a well-ventilated area.

Equipment

1.        Scale of 25 lb (12 kg) capacity sensitive of 0.01 lb (1 gram).

2.        12 × 8.5 × 2.5 inches (300 × 200 × 63 mm) baking pan.

3.        Pan or can with perforated bottom and filter paper to fit bottom.

a.        A 10 oz (300 mL) round sample can is suitable for this purpose.

4.        Glass stirring rod. 

5.        Supply of alcohol in tightly sealed can.

Procedure

1.        Weigh perforated pan or can with filter paper in the bottom.  Record weight.

2.        Place sample of wet soil in perforated pan or can; weigh and record weight.

3.        Place perforated pan or can in larger pan and stir alcohol into the soil sample with a glass rod until the mixture has the consistency of a thin mud or slurry.

a.        When stirring, do not disturb the filter paper on the bottom.

b.        Clean the rod.

4.        Ignite the alcohol in the other pan and in the sample and burn off all alcohol.

5.        Repeat the process three times or until successive weighings indicate no reduction in weight after each time burning.

6.        After final burning, weigh perforated can or pan and dry soil, and record weight. 

7.        The weight of dry soil equals the weight minus weight of perforated pan or can and filter.

8.        Calculate moisture content as shown in Section J though L of Section 1015.02.H.3.

Gasoline-Burning Drying Method

Application

This is a quick and simple method of drying.  However, the gasoline burns at such a high temperature that it should be used only to dry granular materials.  This method should only be conducted outside.

Equipment and Procedures

This method of drying is similar to the alcohol-drying method with the exception that the perforated pan and filter are not used.  The gasoline can be mixed with the sample in the baking pan and burned in the pan.  Except for this, the test is run exactly the same as the alcohol-burning method, described in Section 1015.02.H.5.

Compaction Testing Requiring an Aggregate Correction (1015.06.C.2)

The Aggregate Correction Problem

As detailed in Section 1015.01.E.3 Coarse Aggregate Problem, the moisture-density relationship is very good for soils passing the 3/4-inch (19 mm) sieve as it relates to the field compaction of soils.  There are problems when this relationship is extrapolated to soils larger than the 3/4-inch (19 mm) sieve material or for granular soils.  Corrections must be made to account for these materials.  In certain circumstances, field densities do not correspond to the laboratory results.

Figure 1015.03.A details a plot of adding or subtracting coarse aggregate to a soil and the resulting change in the moisture-density curves.

As you add gravel or add 3/4 inch (19 mm) material to the soil, the optimum moisture content shifts to the left and the maximum dry density increases.  The average increase in density is approximately about 1 percent per 10 percent of material retained on the 3/4-inch (19 mm) sieve.

Figure 1015.03.A - Coarse Aggregate Effects

If you sieve the material through the 3/4-inch-sieve, remove 20 percent coarse aggregate, and do not consider this, you could easily be one or two curves lower than intended.

This correction usually increases the maximum dry density and reduces the optimum moisture content.  This effect is taken care of on the Compaction Form CA-EW-6.

Use the correction on the CA-EW-6 Compaction Form where more than 10 percent but less than 25 percent of the material is retained on the 3/4-inch (19 mm) sieve.  See Figure 1015.03.B, Aggregate Correction Method.

Figure 1015.03.B - Aggregate Correction Method

Caution: Sand which is almost pure may have between 10 to 25 percent retained on the 3/4 inch-sieve.  A test section method would be used in this case.  This method is to be used with Fine Grained Materials with significant granular material retained.

Using Form CA-EW-6 Nuclear Gauge Compaction with an Aggregate Correction

A completed form is detailed in Figure 1015.03.C.  The general sections of this form are as follows:

Figure 1015.03.C - Completed CA-EW-6 Compaction Form

(Pictures added for clarity)

I. Nuclear Gauge Readings

Lines 1 thru 5 are explained in Section 1015.02.D.

II. Remove the Soil from under the Gauge and Sieve thru a 3/4 inch Sieve

This section is a straightforward calculation of the stone retained on the 3/4-inch sieve.  Calculate through lines 6 through 10.

The percentage on line 10 is represented by the following equation:

Percent of Stone in Sample =

Weight of stone retained

× 100

Weight of total soil sample

III. Proctor Test Using the Soil passing the 3/4-inch Sieve

See Section 1015.02.F, Section D, and 1015.01.B.2 for an explanation of lines 11 thru 14.

IV. Pick the Curve for the Ohio Density Curves Using No. 14 and (No.5 or 16)

See Section 1015.02.F for an explanation of lines 15 through 18.

V. Compaction Calculation When Line 10 is less than 10 percent

Line 19 is explained in Section 1015.02.G.

VI. Compaction Calculation When Line 10 is greater than 10 percent and less than 25 percent

This section uses Figure 1015.03.D, Aggregate Correction Graph A, and Figure 1015.03.E, Moisture Correction with an Aggregate Correction, to find a new maximum dry density and optimum moisture.

The Nuclear Gauge Test is similar to Section 1015.02 with the exceptions being the calculation of the percent retained on the 3/4-inch sieve on line 10 in Section II and Section VI is new.

Calculate a New Maximum Dry Density

This section details Figure 1015.03.D, Aggregate Correction Graph A.

The instructions are on the graph.

1.        The inputs needed are:

a.        The specific gravity of the stone retained on the 3/4-inch sieve. 

                                                               i.      The typical values are listed on the graph.

b.        The maximum density found on line 18: 109.6 lbs/ft3.

c.        The percent retained on the 3/4-inch sieve on line 10: 20 percent.

2.        Draw a line between the specific gravity and the value on line 18.

3.        Input line 10 value on the bottom of the graph and draw a vertical to the line drawn previously.

4.        Continue the line to the left on a right angle to the corrected maximum dry density.

5.        Input this value found on line 20 on the CA-EW-6.

This is the corrected maximum dry density: 116.5 lbs/ft³.

Figure 1015.03.D - Aggregate Correction Graph A

Determine a New Optimum Moisture

New optimum moisture is found by inputting the new maximum dry density into the maximum density values in the upper right hand corner on Figure 1015.03.E.

Figure 1015.03.E - Moisture Correction for an Aggregate Correction

For example, the maximum dry density on line 20 is 116.5 lbs/ft³.  This value is between curve K (117) and L (114.5).  The new optimum value is 13.5 percent which is the moisture corresponding to the next highest curve which is Curve K.

Compaction, Difference in Optimum Moisture Content and Zero Air Voids

The compaction, the difference in optimum moisture content, and the zero air voids are calculated on lines 22 to 24. 

Figure 1015.03.F - Zero Air Voids Curve

Figure 1015.03.G - Outline for Using Forms CA-EW-5 and CA-EW-6 (1 of 2)

Figure 1015.03.H - Outline for Using Forms CA-EW-5 and CA-EW-6 (2 of 2)

Figure 1015.03.I - Compaction and Testing Guide

Compaction Testing for Granular Materials (1015.06.C.1)

General Explanation

This section describes how to perform compaction testing for materials used as granular soil, sand, structural backfill Type 1 or 2, 304, 411, select granular backfill for MSE walls, granular material Type A, B, C, D or F, or any materials that requires a test section.

The dry density of the material is used for compaction control.  The wet density method is no longer used.

Moisture-density Proctor curves were originally developed for use on cohesive (clays and silts) soils.  Errors or complications arise when trying to extrapolate these principles to other materials.  This is the reason the Engineer or Inspector is given the latitude to choose density requirements that are based on the test section results. 

A one-point Proctor method using the typical density curves may be used for granular soils.  The top curves of the Ohio Typical Density Curves A through E are usually chosen in this case.  These curves will only work in a very limited number of cases.  This method should only be used as a last resort.

These materials must have a moisture-density curve made a few weeks before the Contractor proposes to use the material.  Curves may be made in the field or by the Laboratory.

Making a moisture-density curve for these materials is the same procedure explained in Section 1015.01.B.  A typical moisture-density curve for a granular material is shown in Figure 1015.04.A.

Figure 1015.04.A - Typical Granular Moisture-Density Curve

The district should contact the Office of Geotechnical Engineering to have a moisture-density curve made.

The maximum dry density and optimum moisture content data obtained from this curve may or may not work in the field.  The following are examples and further explanation of some of the problems associated with the density control of these materials.

Examples of Density Problems

Using a Sandy Material

It may not be possible to obtain the maximum density of the curve no matter how or with what equipment the Contractor uses to compact the material.  This is particularly true for sandy material with silt fines.

Reason

The Proctor mold used to produce the moisture-density curve confines the sand in all directions.  In the field, since sand doesn't interlock or knit together well without being confined, the roller will squeeze the material laterally. The Proctor maximum densities may not be obtained in the field.

The sand may not even support the weight of the roller.  The lab and field confining pressures and compactive effort are not compatible in this case.

This is shown in Figure 1015.04.B

Solution

Use the test section maximum density.

Using a Well Graded Granular Material like 304

In this case, the maximum dry densities obtained in the field, using the test section method, often exceed the maximum dry density of the moisture-density curve.

Reason

The 304 type material is well interlocked and allows the roller to transfer more energy, compactive effort, or load to the material. 

This roller load or energy is much larger than the Proctor hammer load of 5.5 lbs. (2.5 kg) dropped 12 inches (305 mm) in three lifts.

This is shown in Figure 1015.04.B.

Figure 1015.04.B - Maximum Density Problems

Solution

Use the test section maximum density.

Compacting on a Soft Foundation

If the material is being compacted on a soft foundation, then the maximum density cannot be achieved.  Excessive rolling will only result in pumping and creating an unstable foundation.

This applies to all types of materials. You cannot compact good material over bad material and expect to achieve a maximum density.  You cannot compact material on jello-type material to a maximum density either.  The maximum test section densities, if taken at all, would be less than the maximum curve value.

Compacting in Confined Spaces (1015.04.B.4)

There are a variety of locations where light equipment is used to compact material.  Some examples are for:

1.        Pipe backfill.

2.        Manhole backfill.

3.        Around abutments.

4.        MSE walls.

The potential maximum density is limited to the type of equipment used to compact this material in these confined spaces.

Throughout the specifications for these items, ODOT requires minimum compaction equipment weight for these areas where a test section is used for compaction acceptance.

The maximum density that can be achieved is proportional to the heaviest equipment that can be used in these locations.  The maximum density that can be achieved in these locations is usually less than the moisture-density curve value.

Moisture Problems

The granular material should be brought on site at or near optimum moisture.  When this is not the case, moisture should be added before rolling occurs.  This is particularly important for 304 gradation materials since this material cannot readily absorb water.

In 304.03, it is required that the stockpile of 304 material have a moisture content of at least 2 percent below optimum.

Optimum moisture from the Proctor moisture-density curve of granular materials is not always correct.  Sometimes the granular material begins to roll or pump when the material is compacted at or near optimum moisture obtained from the moisture-density curve.  This is caused by excess water in the material and the difference between the field and curve confining forces.  In this case, dry the material until stability is achieved; usually 1 to 3 percent below optimum will work.

Summary of the Moisture-Density Problems

A granular moisture-density curve should always be used to estimate the maximum density and optimum moisture.  When using these materials, the Proctor moisture-density curve is used as a guide; the exact maximum density and optimum moisture can only be found in the field.

The test section method of compaction acceptance compensates for:

1.        Material differences.

2.        Moisture-density curve and potential field density differences.

3.        Moisture problems.

4.        Soft foundations.

5.        Confined construction.

The maximum density determined in the field is relative to all of the above.

Equipment and Compaction Testing (1015.04)

The equipment used for compaction testing is listed in 1015.04.

The compaction testing is the same as in section 1015.02.D, except for the following:

1.        A Proctor is not taken for every test.

a.        Only used to obtain the moisture-density curve.

2.        The “Backscatter Mode” on the gauge is used.

a.        Ensure that the surface voids are all filled or the surface texture is the same.

b.        Variation in the measurements will result.

3.        Use Form CA-EW-5.

Minimum Roller Weights for Test Sections

Throughout the specifications, you will find minimum roller weight requirements when a test section method is used for acceptance.

The following is from C&MS 203.06.A, page 92.

“For soil or granular material, when a test section is used, use a minimum compactive effort of eight passes with a steel wheel roller having a minimum weight of 10 tons (9 metric tons).”

The maximum potential obtained in the field is relative to the roller weight used in the test section.  Therefore, minimums were established to fit the field conditions.  You will notice that the confined areas have a much lower minimum weight and less maximum acceptance value.

Do not be confused by the word centrifugal force.  It is only the effective weight when including the vibration of the equipment.

Procedure for Constructing a Test Section Method A (1015.06.C.3)

Method A is used when the moisture-density curve can be established to estimate the maximum density and optimum moisture.

The following is an outline of the procedure:

1.        Test section size is 400 square yards (for embankment or aggregate base).

2.        Spread the material at the correct lift thickness.

a.        Usually 6 to 8 inches.

3.        Moisture content at - 1 to + 1 of optimum.

a.        Water or dry throughout the lift.

b.        Reduce moisture if unstable.

4.        Compact with two passes.

5.        Take a compaction test.

a.        Mark the location with paint.

b.        Record on line 6 of form CA-EW-5.

6.        Compact with one more pass and continue testing until:

a.        No further increase in density.

b.        Or the density decreases.

7.        Once a maximum is obtained.

a.        Make two additional passes and take one additional test.

b.        Verifies the maximum value (Verification Test).

8.        Record the total number of passes.

a.        Use line 9 of CA-EW-5.

9.        Use this number of passes or the specification minimum in the production area. 

10.     Compact the production area to at least 98 percent of the test section maximum.

There are statements throughout the specifications that require a minimum number of passes.  Experience has shown that these minimum passes for the different materials result in more uniform compaction in the production areas.

If the specification calls for 8 passes, use the 8 passes even though the test section may show that 6 passes are needed to obtain a maximum.  More production area tests will pass by using these minimum passes.

There are also statements throughout the specifications that allow a decrease in minimum number of passes, such as:

“The Engineer may reduce the minimum passes if the passes are detrimental to compaction.”

There are also statements about making a new test section when conditions change.

“Construct a new test section if the pipe type, bedding material, backfill material, or trench conditions change.”

All of these statements allow the Engineer to control the work to meet the field conditions and to obtain maximum densities.

Table 1015.06.A – Test Section Value Examples (‘X’ denotes Maximum Used)

Passes

2

3

4

5

6

Verification Passes (2)

Density

126

134

135

140X

122

125

110

108

112

116

116X

109

120

129

132

130

145 (Take more Tests)

Test Section Method B (1015.06.C.3)

This type of test section is used when a moisture-density curve cannot be made or is not available at the time of construction.  Recycled materials, such as some foundry sands or fly ash can be tested this way.  Since the maximum density or optimum moisture are unknown, we have to create the field curve.

Use the same procedure as in Section 1015.05, except for the following.

1.        Place the material in the required lifts.

a.        Bone dry (0 to 3 percent).

2.        Compact and test until:

a.        A maximum value is reached.

b.        Record the density on line 6 on the CA-EW-5.

c.        Record the number of passes on line 9.

3.        Place new material.

a.        At a new location.

b.        At a moisture content 2 percent higher.

4.        Compact and test to a maximum value.

5.        Repeat the procedure.

a.        At higher moisture until.

                                                               i.      Maximum value is achieved.

                                                              ii.      Two test sections have the same or lower densities.

                                                            iii.      Material becomes unstable.

6.        Use this maximum density, optimum moisture, and number of passes in the production areas.

Figure 1015.06.A - Typical Fly Ash Curves

Test Section Method C (1015.06.C.3)

This test section is used for open graded material, such as non-stabilized drainage base.  It can also be used for open graded aggregate bases where the surface texture is very open and/or non-uniform.

The test section procedure is the same as detailed in 1015.05 except for the following:

1.        Place and compact the material at 1.5 percent above saturated surface dry (SSD).

2.        Construct a test section.

a.        400 square yards.

b.        Take three tests.

c.        Average them.

d.        Compare the averages.

3.        The maximum dry density is reached when:

a.        A maximum density average is achieved.

b.        The aggregate breaks.

c.        Whichever comes first.

4.        Take 10 tests in the control section.

a.        Use 98 percent of this density as the control section maximum.

5.        For acceptance.

a.        Take five tests in a 5,000 square yard lot.

b.        This average must be greater than 98 percent of the control section maximum.

Compaction Testing for Shale (1015.07)

Compaction testing for shale will depend on the durability of the shale.  Perform the durability test (Bucket test) outlined in 703.16.D in the C&MS.  The compaction testing is directly associated with the results.  It provides a ready means to determine what test method to use for compaction acceptance.

In practice, different materials will always be mixed together in a fill situation.  However, the durability test gives a good indication of how the material should break down during compaction and is an excellent way to determine how to test the compaction of the shale.

Compaction Acceptance (1015.08)

Compaction acceptance is always based on the dry density of the material.   After the material is compacted, the dry density does not change with the addition or reduction of water, while the wet density does increase with the addition of water and decrease as the material dries.

Number of Tests (1015.09)

Use Forms CA-EW-5 and CA-EW-6 for recording and reporting results of compaction tests.  Retain these test reports in the project files.  Keep these test reports in the folders of the items of work.

This section outlines the lot size and number of tests that are used on each lot for acceptance.

Under normal field conditions, the number of density and moisture checks required should not be that great after the initial period of adjustment, assuming that the work is proceeding smoothly and materials being compacted are uniform. 

The Engineer and Inspector will learn to judge the moisture content of the material quickly by appearance and feel.  If adequate densities are obtained and the proper moisture content is maintained, the job of inspection may consist of deciding on the number of passes of the roller required for satisfactory test section density and ensuring that this number of passes is made. 

Under such conditions, only one or two density checks per day may be required.  Where conditions are more variable, density and moisture checks may be needed as often as once an hour.  The Engineer and Inspector can determine the exact number of checks required.

Documentation Requirements - Supplement 1015 Compaction Testing of Unbound Materials

1.        Document all materials, inspection, and compaction information on Form CA-EW-12.

2.        For Items 203, 204, 205, 206, 840, 503, 611, Soil Embankment, and all items that 203 Embankment is specified:

a.        If less than 10 percent of material passes the 3/4-inch sieve, document on form CA-EW-5.

b.        If more than 10 percent, but less than 25 percent of the material passes the 3/4-inch sieve, document on form CA-EW-6.

c.        If more than 25 percent of the material passes the 3/4-inch sieve, document on form CA-EW-5.

3.        Items 203, Granular Embankment; 203 Granular Material Types A, B, C, D, or F; Item 304, 411, 503, Select Granular Backfill for MSE Walls; and Structural Backfill and Granular Embankment, document on form CA-EW-5.