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