Control of materials is a necessary and important part of every construction project. The intent is to assure 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 gives you the item which in turn references the appropriate material specification (700 series) used in conjunction with the material sampling and testing program manual gives you the proper procedure for material acceptance. Additional information may be found on the material code screen, (MATL) on CMS/TAS.
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
The District Highway Management Administrator will determine the extent of application of responsibilities for material compliance under the policy for Material Documentation Process, 515-001(P) based on project staffing level/and or expertise. It may be applied on either a wholesale or project by project basis.
Under this policy the Engineer may approve certain materials as listed below and may modify the project bill of materials. Materials that maybe 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 106.031.
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 insure compliance with material approval requirements.
The material certification for the projects will be approved by the District Highway Management Administrator.
The CMS will be used to document material requirements.
· Materials approved by Engineer
o Project personnel will complete appropriate documentation (TE 30, etc.) create sample ID's 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 (TE31 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 insure 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.
Personnel from the District Test Lab will conduct quality assurance reviews during the actual construction phase of projects. These reviews will assure 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 Engineering Policy will establish guidelines for performance of the quality assurance reviews.
In the event that unapproved 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 then the Engineer must follow the process to modify the contract to allow these materials to remain in place. See Standard Procedure 510-009(SP).
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 minimum visual inspection.
· Standard Operating Procedures
o Standard Operating Procedures (SOP'S) are technically focused unit specific procedures affecting 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. (Appendix H)
· 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.
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 CMS 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 also 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.
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, the 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 a 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 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 assure 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.
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 also 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. When these pockets are sufficiently large that non-uniform areas can be observed in the material placed on the grade, however, the results are unsatisfactory and corrective measures assuring 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.
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.