U.S. Department of Transportation
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Federal Highway Administration Research and Technology
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This report is an archived publication and may contain dated technical, contact, and link information |
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Publication Number: FHWA-HRT-04-046 Date: October 2004 |
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The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction and providing qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. At a minimum, values for percent air, slump, unit weight, and gradation must be plotted on control charts. QC tests include aggregate gradation, slump, air content, unit weight/yield, compressive strength, flexural strength, material passing #200, percent moisture in aggregate, temperature, and density of fresh concrete. Cores are to be tested once per each sublot, where a sublot is the day's lot production divided into five sublots of equal surface area.
QA is the responsibility of the engineer and is accomplished through verification testing by Kansas DOT. The engineer conducts verification testing on aggregate gradation, slump, air content, unit weight/yield, compressive strength, flexural strength, material passing #200, percent moisture in aggregate, temperature, and density of fresh concrete.
Acceptance or rejection of material is based on the contractor's QC tests as verified by the engineer's tests. Should the results of the two tests disagree, the engineer's results will be used to determine acceptance or rejection. If the test results are disputed, referee testing will be conducted on additional samples by an independent laboratory. The referee test results will then be used for acceptance.
Pay factors are assigned for smoothness, compressive strength, and thickness. The smoothness pay factor is based on the California profilograph. Values for this pay factor were not provided. Pay factors for thickness and compressive strength are based on a quality index for each characteristic. The quality index (Qi) is calculated as follows:
(64)
where: Xavg = average measured thickness or compressive strength of all cores in the lot
LSL = lower specification limit
S = standard deviation of all thickness or compressive strength samples for the lot
The quality index is then used to calculate a pay adjustment factor according to the following table:
Table 135. Kansas concrete thickness and comprehensive strength pay adjustment.
Quality Index | Pay Adjustment Factor |
---|---|
> 1.71 | 103% |
1.56-1.71 | 102% |
1.41-1.55 | 101% |
1.26-1.40 | 100% |
0.00-1.25 | * |
< 0 | 50% |
*Calculated as P = 60 + (Q × 32)
A composite pay factor for the lot is then calculated as Pc = (Pt × Ps)/100.
Table 136. Kansas QC/QA tests.
Test Sampling | Location | QC Testing by Contractor | Verification Testing by Kansas DOT |
---|---|---|---|
Aggregate gradation | Feed bins | One test per 1000 tons | One per 30,000 tons |
Slump | Truck | One per 500 yd3 or minimum of one per day | One per day |
Air content (plastic concrete) | Truck | One per 500 yd3 or minimum of one per day | One per day |
Cores | Roadway | One per sublot | One per lot |
Temperature | Truck | One per 500 yd3 | One per day |
Beams | Truck | As required for opening to traffic | One set per week |
Unit weight | Truck | One per 500 yd3 or minimum of one per day | One per day |
Material passing #200 (washed) | Feed bins | One test per 1000 tons | One per week |
Smoothness | Roadway | NA | NA |
Thickness | Roadway | One per sublot | One per lot |
Density of fresh concrete | Roadway | One complete transverse profile initially, then one per ½ day | One per week |
NA = Not applicable
1 cubic yard (yd3) = 0.765m3, 1 ton = 0.907 Mg
The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction and providing qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. At a minimum, the contractor must have a level 1 PCC technician at the job site, as well as a level 2 PCC technician at the plant during mixture production and placement. QC tests include aggregate gradation, slump, air content, unit weight/yield, temperature, and compressive or flexural strength.
The engineer is responsible for all QA testing on split samples. The split sample is one of two equal portions of a field sample. At the engineer's discretion, he/she may also obtain independent field samples for testing. The results of the QA tests will be made available to the contractor as soon as they are completed. In the event that the contractor's or the engineer's tests for air content and strength are not within specification limits, referee testing will be conducted by Illinois DOT or by a mutually agreed upon laboratory at the contractor's option.
Acceptance of the material is based on: contractor's compliance with all contract documents for QC, validation of the contractor's QC test results by comparison with the engineer's QA tests, comparison of the engineer's QA test results with the specification limits using samples independently obtained by the engineer, and referee test results for unresolved failing tests obtained by the contractor or the engineer.
Pay factors are assigned for smoothness and thickness.
Table 137. Illinois QC/QA tests.
Test Sampling | Location | QC Testing Frequency by Contractor | Verification Testing Frequency by Illinois DOT (split sample) |
---|---|---|---|
Aggregate gradation | At plant from bins or stockpiles | One per 2500 yd3 | First test performed by the contractor at the beginning of the project, and then a minimum of 10% of the tests required by the contractor |
Slump | Job site | One per 500 yd3 or minimum of one per day | First three tests performed by the contractor at the beginning of the project, and then a minimum of 10% of the tests required by the contractor |
Air content (plastic concrete) | Job site | One per 100 yd3 or minimum of one per day | First three tests performed by the contractor at the beginning of the project, and then a minimum of 10% of the tests required by the contractor |
Strength | Laboratory | One per 1250 yd3 or minimum of one per day | First test performed by the contractor at the beginning of the project, and then a minimum of 10% of the tests required by the contractor |
Smoothness | Job site | NA | NA |
Thickness | Job site | NA | NA |
Temperature | Plant | As needed to control production | NA |
NA = Not applicable
1 yd3 = 0.765 m3
The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction and providing qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. At a minimum, the contractor must perform QC tests on the unit weight of plastic concrete, aggregate gradation, flexural strength, air content, slump, and water-to-cement ratio.
The engineer is responsible for QA and acceptance of the material. QA is accomplished by conducting verification sampling and testing, observing the QC sampling and testing, taking additional samples for testing at any time, and monitoring control charts. Results of the verification tests will be made available to the contractor as soon as they are completed. Verification testing frequency will be at the discretion of the engineer, but must not be less than 10 percent of the QC tests. Verification testing will be conducted on those properties tested for QC.
Acceptance of the material will be based on the contractor's QC test results as long as the results agree with Iowa DOT's test results. Acceptance for thickness will be based on samples tested by the engineer. Coring for thickness will be on a lot-by-lot basis, where 1 day's production is considered a lot, which is divided into three equal sublots for testing.
Pay factors are assigned for smoothness, thickness, and flexural strength. The pay factor for smoothness was not provided. The pay factor for thickness is determined using the following table:
Table 138. Iowa pay factors for thickness.
Thickness Index* Range (mm) | Percent Payment | Thickness Index* Range (mm) | Percent Payment |
---|---|---|---|
0.00 or more | 103 | -13.98 to -15.24 | 91 |
-0.01 to -1.27 | 102 | -15.25 to -16.51 | 90 |
-1.28 to -2.54 | 101 | -16.52 to -17.78 | 89 |
-2.55 to -3.81 | 100 | -17.79 to -19.05 | 88 |
-3.82 to -5.08 | 99 | -19.06 to -20.32 | 87 |
-5.09 to -6.35 | 98 | -20.33 to -21.59 | 86 |
-6.36 to -7.62 | 97 | -21.60 to -22.86 | 85 |
-7.63 to -8.89 | 96 | -22.87 to -24.13 | 84 |
-8.90 to -10.16 | 95 | -24.14 to -25.40 | 83 |
-10.17 to -11.43 | 94 | -25.41 to -26.67 | 82 |
-11.44 to -12.70 | 93 | -26.68 to -27.94 | 81 |
-12.71 to -13.97 | 92 | -27.95 or less | 80 |
* The thickness index is determined as follows: TI = (Xavg - S) - T, where Xavg = mean core length for the section,
S = core length standard deviation for the section, and T = design thickness. Pavement, represented by cores,
which is deficient from the design thickness by 25 mm or greater shall be replaced. Payment for thickness will be
based on the percentage of the contract price.
The pay factor for flexural strength is determined by subtracting 1 standard deviation from the mean strength according to the following table. The average strength is based on three beams.
Table 139. Iowa pay factors for flexural strength.
Strength (lbf/inch2) | Pay Factor |
---|---|
< 450 | Remove |
450-474 | 70 |
475-499 | 75 |
500-524 | 80 |
525-549 | 85 |
550-559 | 90 |
560-569 | 92 |
570-579 | 94 |
580-589 | 96 |
590-599 | 98 |
600-624 | 100 |
625-649 | 101 |
650-674 | 102 |
≥ 675 | 103 |
1 lbf/inch2 = 6.89 kPa
The composite pay factor was not provided; however, it appears to be the individual pay factors multiplied together times the contract price.
Table 140. Iowa QC/QA tests.
Test | Sampling Location | QC Testing Frequency by Contractor | Verification Testing Frequency by Iowa DOT | Acceptance by Iowa DOT |
---|---|---|---|---|
Aggregate gradation | Feed bins | Two per day | At least 10% of QC tests | Verification of QC by Iowa DOT's tests |
Air content (plastic concrete) | Truck | First load and then one per 500 yd3 | At least 10% of QC tests | Verification of QC by Iowa DOT's tests |
Water-to-cement ratio | Truck | Two per day | At least 10% of QC tests | Verification of QC by Iowa DOT's tests |
Unit weight of plastic concrete | Truck | One per day | At least 10% of QC tests | Verification of QC by Iowa DOT's tests |
Thickness | Roadway | NA | NA | Five cores per sublot |
28-day flexural strength | Truck | One per 1000 yd3 | At least 10% of QC tests | One set of three beams as determined by engineer |
NA = Not applicable
1 yd3 = 0.765 m3
All plants producing concrete for New Jersey DOT projects shall have a QC plan in place, as outlined in "Requirements for a Portland Cement Concrete Quality Control Plan," June 25, 1998. A QC technician who is certified by the American Concrete Institute as grade I must be available during the production of concrete for any New Jersey DOT project. QC tests for slump, air content, compressive strength, aggregate gradation, and temperature are conducted at the plant. Concrete provided by any producer who has met applicable design, control, and acceptance testing requirements will be presumed to be in compliance with New Jersey DOT's standards at the time of delivery. However, the presumption will not waive the engineer's right to impose pay adjustments.
Acceptance of the material is determined through acceptance testing by New Jersey DOT. Acceptance will be based on the results of the slump, strength, and air content tests. Acceptance for compressive strength, slump, and air content will be on a lot-by-lot basis, with a lot being equal to 1 day's production. Acceptance tests will be conducted at a frequency of five per lot.
Pay factors are assigned for air content and compressive strength. The pay factor for compressive strength and air content will be determined by the percent defective within the lot. Percent pay adjustments (PPA) are calculated using the following two equations:
(65)
(66)
The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction. During the preconstruction meeting, the contractor and the engineer will determine the types and frequencies of testing that are required to produce materials that meet the specifications. The contractor must also provide qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. At a minimum, the contractor must have a technician who is certified to develop the concrete design, control the gradation and quality of the aggregates, and perform the required tests. QC testing must be conducted for aggregate gradation, air content, slump, compressive strength, profile index, and thickness.
Acceptance of the material is determined through acceptance testing by North Carolina DOT. Acceptance will be based on the results of the slump, flexural strength, thickness, profile index, and air content tests. Acceptance for slump and air content will be determined at the point of placement at a frequency determined by the engineer. A sample will be obtained immediately after the concrete has been discharged onto the road. Acceptance for thickness and flexural strength will be determined on a lot-by-lot basis, where a lot is 5333.3 yd3 and subsequently divided into four equal sublots. For each sublot, a set of two beams shall be used to test flexural strength. Additionally, two cores shall be taken from each lot to test for thickness. Acceptance testing of the longitudinal profile of the finished pavement must be performed by the contractor in the presence of the engineer.
Pay factors are assigned for profile index, thickness, and flexural strength. The pay factor for the profile index was not provided. The pay factor for thickness is determined from the following table:
Table 141. North Carolina pay factors for thickness.
Deficiency (inches) | Percentage of Price Allowed |
---|---|
0.00-0.20 | 100 |
0.21-0.30 | 80 |
0.31-0.40 | 72 |
0.41-0.50 | 68 |
0.51-0.75 | 57 |
0.76-1.00 | 50 |
1 inch = 25.4 mm
The pay factor for flexural strength is determined from the following table:
Table 142. North Carolina pay factors for flexural strength.
Pay Factor Level | Lower Acceptance Limits | |||
---|---|---|---|---|
Number of Tests in Lot | ||||
3 | 4 | 5 | 6 | |
1.05 | 550 + 0.60R | 550 + 0.66R | 550 + 0.66R | 550 + 0.66R |
1.00 | 550 + 0.58R | 550 + 0.54R | 550 + 0.50R | 550 + 0.46R |
0.95 | 550 + 0.36R | 550 + 0.27R | 550 + 0.23R | 550 + 0.21R |
0.70 | 550 | 550 | 550 | 550 |
Note: R is the difference between the high and low tests in the lot. If multiple deficiencies occur, the payment is determined by successively multiplying the contract price by the appropriate factor indicated for each deficiency.
Table 143. North Carolina QC/QA tests.
Test | Sampling Location | QC Testing Frequency by Contractor | Acceptance Testing Frequency by North Carolina DOT |
---|---|---|---|
Aggregate gradation | Feed bins | Contractor's discretion as needed for control | NA |
Slump | Roadway after discharge | Two per day | Engineer's discretion |
Air content (plastic) | Roadway after discharge | Two per day | Engineer's discretion |
Profile index | Roadway | Three profiles: Two at 3.5 ft inside the outer wheel path and one along the longitudinal joint | Based on QC test |
Thickness | Roadway (coring) | Contractor's discretion as needed for control | Two cores per lot |
Flexural strength | Truck | NA | Two beams per sublot (average) |
Compressive strength | Roadway (coring) | Contractor's discretion as needed for control | NA |
NA = Not applicable
1 ft = 0.305 m
The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction and providing qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. At a minimum, the contractor must have a concrete control technician (CCT) at the plant or job site and a QC technician (QCT) at the job site. QC tests include aggregate gradation, slump, air content, water-to-cement ratio, unit weight/yield, temperature, and compressive strength. QC tests will be conducted on a lot-by-lot basis, where a lot is the total amount of concrete produced for each mix design. This lot will then be divided and tested by the sublot, where a sublot is equal to 75 m3 of material.
The engineer is responsible for all QA. Assurance is accomplished through verification testing, observation of contractor sampling and testing, and additional sampling and testing conducted by the engineer. The results of the verification tests will be made available to the contractor as soon as they are completed. In the event that the contractor's or the engineer's tests are not within specification limits, they shall immediately work together to resolve the difference to avoid having the material rejected as not meeting specifications. Verification testing will be conducted on a lot-by-lot basis, where a lot is the total amount of concrete produced for each mix design.
Acceptance of the material is based on verification of the QC tests by Oregon DOT's tests. For aggregate acceptance, verification of the contractor's test values through check tests completed by the engineer will be used. For plastic concrete, acceptance is based on the QC tests performed by the contractor and on tests conducted by the engineer. The engineer may observe the QC tests performed by the contractor and/or conduct tests on all plastic concrete. Hardened concrete will be accepted based on the statistical analysis of the 28-day strength tests of cylinders cast by the engineer.
Pay factors are assigned for smoothness, thickness, and compressive strength. The pay factor for smoothness is determined by the following equation:
(67)
where: PI = average of the two wheel path profiles for the segment
Quantity = area in m2 represented by the segment
Unit price = price for the concrete shown in the bid schedule
The pay factor for thickness is determined using the following table. No additional payment will be made for pavement exceeding the minimum specification.
Table 144. Oregon pay factors for thickness.
Deficiency in Thickness (mm) | Proportional Part of Contract Unit Price Allowed |
---|---|
0.0-5.0 | 100% |
5.1-7.6 | 83% |
7.7-10.1 | 76% |
10.2-12.7 | 73% |
12.8-19.0 | 63% |
19.1-25.0 | 59% |
The pay factor for compressive strength is based on statistical analysis to determine the total percent within the specification limits. This is then used to determine the pay factor for strength. In no case shall payment exceed the contract price. For pay factors less than 1.00, a pay reduction is calculated as follows:
(68)
A weighted pay factor (WPF) is determined by multiplying PF by a weighting factor fI provided in the contract. The method for determining a composite pay factor (CPF) for these items uses the following formula:
(69)
where: WPF = weighted pay factor
fI = weighting factor
Table 145. Oregon QA/QC tests.
Test | Sample Location | QC Testing Frequency by Contractor | Verification Testing by Oregon DOT | Acceptance by Oregon DOT |
---|---|---|---|---|
Aggregate gradation | Feed bins | One per shift or 500 Mg | One per shift or 500 Mg | Verification of QC by Oregon DOT's test |
Slump | Roadway after discharge | One per sublot | One per lot | Verification of QC by Oregon DOT's test |
Air content (plastic) | Roadway afterdischarge | One per sublot | One per lot | Verification of QC by Oregon DOT's test |
Water-to-cement ratio | Roadway after discharge | One per sublot | One per lot | Verification of QC by Oregon DOT's test |
Yield | Roadway after discharge | One per sublot | One per lot | Verification of QC by Oregon DOT's test |
Thickness | Roadway | One sticking of plastic concrete per 60 lane-meters | Observation of QC test | Observation of QC test |
Compressive strength | Cast in the field | NA | NA | One set of four cylinders per sublot |
Smoothness | Roadway | One pass per wheel path per 200-m segment | Observation of QC test | Observation of QC test |
Temperature | Roadway after discharge | One per sublot | One per lot | NA |
NA = Not applicable
The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction and providing qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. At a minimum, the contractor must have a certified technician to develop the concrete design, control the gradation and quality of the aggregates, and perform the required tests. QC testing must be conducted for aggregate gradation, air content, slump, compressive strength, profile index, and thickness.
QA is accomplished through independent sampling and testing by Pennsylvania DOT for air content, strength, and pavement thickness. Independent assurance testing is conducted to review the QC testing and to check the accuracy of the equipment used for acceptance testing.
Acceptance of the material is determined through acceptance testing by Pennsylvania DOT. Acceptance will be based on the results of the slump, strength, thickness, and air content tests. Acceptance for compressive strength and air content will be on a lot-by-lot basis, with testing conducted on sublots of 1400 yd2 (1170 m2). Acceptance for smoothness will be based on the QC profilograph test.
Pay factors are assigned for profilograph, thickness, air content, and compressive strength tests. The pay factor for compressive strength and air content will be determined by the PWL for the lot. The pay factor for thickness will be determined by coring. The profile index pay factor is determined using a profilograph and assessing the index in inches per mile per lot. After determining the individual pay factors for each of the above characteristics, the lot payment is calculated using the following equation:
(70)
where: Lp = lot payment
Cp = contract price per lot
Ps = payment percentage of the contract price for strength
Pd = payment percentage of the contract price for depth
Pa = payment percentage of the contract price for air content
Pp = payment percentage of the contract price for the profile
Table 146. Pennsylvania QA/QC tests.
Test Sample | Location | QC Testing | Assurance Testing | Acceptance Testing |
---|---|---|---|---|
Aggregate gradation | Feed bins | Varies: Established in QC plan | NA | NA |
Slump | Roadway after discharge | One per 200 yd3 | NA | One per sublot |
Air content | (plastic) Roadway after discharge | One per 200 yd3 | One per two lots | One per sublot |
Profilograph | Roadway | Test as soon as concrete is cured | NA | Based on QC test |
Thickness | Roadway | One core per sublot | One core per two lots | Four cores per lot |
Compressive strength | Cast in the field | Two cylinders per sublot | One cylinder per two lots | Four cylinders per lot |
NA = Not applicable
1 yd3 = 0.765 m3
The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction and providing qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. To complete the required testing, the contractor must provide technicians certified at levels I through IV, depending on the test being conducted. The standard lot size is 6000 yd2 (5000 m2) of surface area of PCC pavement of the same thickness. A sublot is equal to one-fifth of the surface area of a lot. If the final lot is 3000yd2 (2500 m2) or greater, it will be considered a full lot. QC must be exercised on all properties contained in the table entitled QC/QA Tests for Texas.
QA is accomplished through verification testing conducted by Texas DOT. Independent assurance testing is conducted to review the QC testing and to check the accuracy of the equipment used for verification testing.
Acceptance of the material is based on the QC tests and the verification tests. If the contractor's QC test results and the engineer's verification test results are not within tolerances, referee testing will be conducted. If referee tests are requested, the referee test results shall govern.
Pay factors are assigned for ride quality, thickness, and flexural strength. The pay factor for flexural strength is based on the following table:
Table 147. Texas pay factors for flexural strength.
Average Flexural Strength (Three Beams) (lbf/inch2) | Strength Adjustment Factor (SF) |
---|---|
≥ 555 | 1.0000 |
550 | 0.9695 |
545 | 0.9397 |
540 | 0.9106 |
535 | 0.8820 |
530 | 0.8542 |
525 | 0.8269 |
< 525 | Remove or remain with no payment |
1 lbf/inch2 = 6.89 kPa
The pay factor for ride quality was not provided. The pay factor for thickness is determined using the following table:
Table 148. Texas pay factors for thickness.
Thickness Deficiency (inches) | Thickness Adjustment Factor (TF) |
---|---|
> 0.00-0.20 | 1.00 |
> 0.20-0.30 | 0.80 |
> 0.30-0.40 | 0.72 |
> 0.40-0.50 | 0.68 |
> 0.50-0.75 | 0.57 |
The pay adjustment factor for each lot is calculated as AF = (SF)(TF). The pay adjustment for each lot is then calculated as:
(71)
where: BP = bid price
Q = lot quantity of acceptable pavement
Table 149. Texas QC/QA tests.
Test | Sample Location | QC Testing by Contractor | Verification Testing by Texas DOT | Acceptance by Texas DOT |
---|---|---|---|---|
Mix temperature | Plant | One per sublot | One per day | Based on QC, verification, and referee, if required |
Air content (plastic) | Roadway after discharge | One per sublot | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Concrete unit weight | Roadway after discharge | One per sublot | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Making/curing strength specimens | Roadway after discharge | One per sublot | 1 set per 10 sublots | NA |
7-day flexural strength | Roadway after discharge | NA | One per sublot | Based on verification |
Coarse aggregate gradation | Stockpile | One per stockpile per day | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Coarse aggregate loss by decantation | Stockpile One | per 5 PCC production days | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Fine aggregate gradation | Stockpile | One per stockpile per day | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Fineness modulus | Stockpile | One per stockpile per day | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Fine aggregate organic impurity | Stockpile | One per 5 PCC production days | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Sand equivalent | Stockpile | One per 5 PCC production days | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Aggregate moisture content | Stockpile | One per stockpile per day | 1 per 10 QC tests | Based on QC, verification, and referee, if required |
Water-to-cement ratio | Roadway after discharge | One per batch | Review plant printout and calibration | Based on QC, verification, and referee, if required |
Cement factor | Roadway after discharge | One per batch | Review plant printout and calibration | Based on QC, verification, and referee, if required |
Admixture dosage | Roadway after discharge | One per batch | Review plant printout and calibration | Based on QC, verification, and referee, if required |
Coring for thickness | Roadway | One per sublot | NA | NA |
Measuring pavement thickness | Roadway (plastic) | NA |
One per sublot | Based on QC, verification, and referee, if required |
NA = Not applicable
The contractor is responsible for providing a QC plan that must be approved by the engineer prior to construction and providing qualified personnel and equipment to conduct QC testing. The contractor must allow the engineer access to the laboratory to observe any and all testing procedures, calculations, test documentation, and plotting of results. At a minimum, the contractor must have the following certified personnel: aggregate technician 1, PCC technician 1A, PCC technician 2, concrete compressive strength tester, and profilograph operator 1. QC testing must be conducted on the following: aggregate gradation, material passing #200, aggregate moisture, air content, slump, temperature, thickness, profilograph, and compressive strength.
QA is accomplished through verification testing by Wisconsin DOT for air content, strength, and pavement thickness. Independent assurance testing is conducted to review the QC testing and the verification testing. The independent assurance review will be done in accordance with Wisconsin DOT's Independent Assurance program and may include: split-sample testing, proficiency sample testing, witnessing of sampling and testing, review of control charts, and requesting additional samples for testing.
Acceptance of the material is based on the contractor's QC test results. This method of acceptance and payment will continue until it can be shown through verification or the dispute resolution process that the contractor's test results are in error. Acceptance will be based on the results of the strength, thickness, and air content tests.
Pay factors are assigned for profilograph, thickness, and compressive strength. The pay factor for compressive strength will be determined by the lot and will be based on the contractor's QC cylinders fabricated for each sublot. A lot is considered to be 1 day's production divided into equal sublots not to exceed 500 yd3 (380 m3). The pay adjustment will be based on the lot's average strength minus 1 standard deviation. The factor is a dollars per yd2 adjustment. The factor is determined from the following table:
Table 150. Wisconsin pay factors for compressive strength.
Strength (lbf/inch2) | Pay Adjustment ($/yd2) |
---|---|
≤ 2850 | -0.552 |
2850 to 2950 | -0.527 |
2950 to 3050 | -0.452 |
3050 to 3150 | -0.385 |
3150 to 3250 | -0.309 |
3250 to 3350 | -0.234 |
3350 to 3450 | -0.167 |
3450 to 3550 | -0.109 |
3550 to 3650 | -0.050 |
3650 to 3750 | -0.000 |
3750 to 3850 | 0.067 |
3850 to 3950 | 0.125 |
3950 to 4050 | 0.167 |
4050 to 4150 | 0.201 |
4150 to 4250 | 0.226 |
4250 to 4350 | 0.242 |
4350 to 4450 | 0.259 |
4450 to 4550 | 0.268 |
4550 to 4650 | 0.268 |
≥ 4650 | 0.276 |
1 lbf/inch2 = 6.89 kPa, 1 yd2 = 0.836 m2
The pay factor for the profile index will be determined according to the following table:
Table 151. Wisconsin pay factors for the profile index.
Profile Index (inches/mi) | Pay Adjustment per 0.1-mi Section per Lane |
< 19.0 | +$585 |
19.0-25.2 | +$350 |
25.3-44.3 | $0 |
44.4-50.6 | -$230 |
≥ 50.7 | -$940 |
1 mi = 1.61 km, 1 inch/mi = 15.8 mm/km
The pay factor for thickness will be determined according to the following table:
Table 152. Wisconsin pay factors for thickness.
Average Thickness Deficiency (inches) | Pay Adjustment per 250-ft Lane Length Unit |
0-3/8 | $0 |
> 3/8-½ | -$1143 |
> ½-¾ | -$2095 |
> ¾-1 | -$2667 |
1 inch = 25.4 mm, 1 ft = 0.305 m
These factors are applied according to the units listed in the tables.
Table 153. Wisconsin QC/QA tests.
Test | QC Testing by Contractor | Verification Testing by Wisconsin DOT | Acceptance by Wisconsin DOT |
Material passing #200 | Two per day | NA | NA |
Aggregate gradation | 0-1000 tons: One per day 1000-2000 tons: Two per day 2000+ tons: Three per day | NA | NA |
Slump | One per sublot | NA | NA |
Aggregate moisture | Two per day | NA | NA |
Air content | One per sublot | One per lot | Based on QC test |
Profilograph | As soon as concrete has cured enough for testing | NA | Based on QC test |
Thickness | Two per 250 ft | Two per day | Based on QC test |
Compressive strength | Three cylinders per sublot | One per five lots | Based on QC test |
Temperature | One per sublot | NA | NA |
NA = Not applicable
1 ft = 0.305 m, 1 ton = 0.907 Mg