ITEM 602  MASONRY

602.01  Description

602.02  Materials

602.03  Construction Requirements

602.04  Method of Measurement

602.05  Basis of Payment

 

602.01 Description.  This work consists of constructing headwalls, pipe cradles, collars, and other brick and masonry units of the types and sizes specified.

Use all suitable material in the work.  Alternatively legally use, recycle, or dispose of all excavated materials according to 105.16 and 105.17.

602.02 Materials.  Furnish materials conforming to:

Backfill......................................................................... 203

Concrete, Class C........................................... 499 and 511

Water for grout and mortar...................................... 499.02

Reinforcing steel...................................................... 509.02

Cement for mortar.......................... 701.01 through 701.07

Sand for mortar........................................................ 703.03

Granular base ......... Granular material Type B (203.02.R)

Brick and masonry units............... 704.01, 704.02, 704.03

Nonshrink mortar.................................................... 705.22

Lime for mortar....................................................... 712.04

 

602.03 Construction Requirements.  Construct the designated items as shown on the plans.

A. Excavate to dimensions that provide ample room for construction.  Remove obstructions as necessary to perform this work.

Protect the sides of all excavations from caving by providing suitable sheeting, shoring, and bracing.  Use excavation methods that do not disturb the original material below the bottom of footers or below the additional 6 inches (150 mm) required for precast structures.

If the material found at the bottom of the headwall or below the additional 6 inches (150 mm) required for precast structures is not suitable for a foundation, excavate to further depth to provide a suitable foundation. Backfill the void left by the additional excavation with granular base.  The Department will pay for this additional work according to 109.05.

Backfilling shall follow completion of the work as closely as the construction will allow.  Backfill with granular base or soil. Place backfill in 6-inch (150 mm) loose lifts.

B. Compaction requirements are according to Item 203 except for the following:

Four passes per lift with additional passes as required until 95 percent compaction is reached.  Use compaction equipment with a minimum total weight of, or minimum centrifugal force of, 1 ton (0.9 metric ton).  Supply the manufacturer’s specifications for this equipment to verify these requirements.

C. Cast-in-place structures are headwalls, pipe cradles, collars, and other units. Construct cast-in-place structures according to the corresponding Standard Construction Drawing using methods specified in Items 499, 511, and 509.

D. Pre-cast structures are half height headwalls for conduits up to a maximum of 72 inches (1800 mm). These pre-approved pre-cast structure drawings are on file in the Office Material Management. With the submission of the TE-24 from an approved manufacturer furnish stamped, approved from the Office of Structural Engineering design drawing sheets.  Pre-cast half-height headwalls for elliptical conduits may be constructed from templates of the actual conduit being supplied, up to a maximum 72 inch (1800 mm) (round equivalent) to the project to ensure the opening is OD plus one inch.  Submit drawings to the Office of Structural Engineering for approval, on a project by project basis, of pre-cast half-height headwalls for elliptical conduit.  Non-pre-approved drawings are required to be submitted to the Office of Structural Engineering for approval. Allow 4 weeks for approval.  Failure to furnish the stamped, approved design drawing sheets will result in rejection of the pre-cast structure.  The drawings will include the following:

1.  All manufacturers are pre-approved per Supplement 1073.

2.  All reinforcing steel will be epoxy coated.

3.  All HW-2.1 SCD require wire insert details.

4.  Attachment detail for metal or plastic conduit per SCD HW2.1.

5.  Non-corrosive lifting devices.

6.  Maximum opening is conduit outside diameter plus 1 inch (25 mm) for each conduit material type.

7.  All openings to be filled with nonshrink mortar including all lifting device voids.

8.  Changes in pre-approved drawings are the same as non pre-approved drawings.

9.  Detail how the 6 inch (150 mm) extension is treated if required.

10. Fill the void between the precast half height headwall and the conduit by using nonshrink mortar.

11. Apply marking, either stamped or painted, to the headwall to ensure each headwall size is matched to the proper conduit size and material type.

E.  Pre-cast structures for slab footers, cut off walls, wingwalls, and headwalls for use with Items 706.05, 706.051 and 706.052 that conform to the manufacturers pre-approved design. Approved manufacturers that change their designs are considered non-approved designs. The pre-approved design is on file in the Office of Structural Engineering.  With the submission of the TE-24 from an approved manufacturer furnish stamped, approved from the Office of Structural Engineering design drawing sheets.  Non-approved designs are required to be submitted to the Office of Structural Engineering for approval. For non-approved designs submit structural design criteria, analysis method and structural details for approval to the Office of Structural Engineering. Allow 4 weeks for approval. Furnish 7 shop drawings to the Office of Structural Engineering for construction project pre-approved pre-cast structure review and approval. Allow 4 weeks for review and approval.  Failure to furnish the stamped, approved design drawing sheets will result in rejection of the precast structure.  Include the following:

1.  All manufacturers are pre-approved per Supplement 1073.

2.  All reinforcing steel will be epoxy coated.

3.  Furnish PE signed sealed dated.

4.  Non-corrosive lifting devices.

5.  All openings to be filled with non-shrink mortar including all lifting hook voids.

F.  Masonry units structures are headwalls, pipe cradles, collars, and other units. Thoroughly wet masonry units  before laying the mortar. Lay masonry units with full mortar joints. Take adequate precautions to prevent the mortar from freezing.  Do not set masonry units having a temperature of 40 °F (4 °C) or less with mortar until heated.  When required, heat to ensure that a temperature of 50 to 80 °F (10 to 27 °C) is obtained throughout the entire masonry units. Cure the exposed surfaces of the masonry units by covering with wet burlap for 48 hours or by applying curing membrane according to Item 511. Construct the masonry units structures according to the corresponding Standard Construction Drawing. Use one of the following mortars:

1.  One part Portland cement to two parts sand by volume.  The Contractor may add lime in an amount not to exceed 10 percent of the cement by weight

2.  One part masonry cement to two parts sand by volume.

602.04 Method of Measurement.  The Department will measure Brick Masonry, Block Masonry, and Concrete Masonry by the number of cubic yards (cubic meters) calculated from dimensions shown on the plans.

602.05 Basis of Payment.  When a precast structure is used, payment is based on the number of cubic yards (cubic meters) required for the cast in place item and is considered full compensation for construction of the precast structure.

The Department will pay for accepted quantities at the contract prices as follows:

Item           unit                                Description

602             Cubic Yard                      Brick Masonry
                       (Cubic Meter)

602             Cubic Yard                      Block Masonry
                       (Cubic Meter)

602             Cubic Yard                      Concrete Masonry
                       (Cubic Meter)