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In addition to the random acceptance samples taken from each lot, the Engineer may sample and reject material which appears to be defective. Such rejected material shall not be used in the work. The results of tests run on rejected material will not be included with the lot acceptance tests.

401.22 Acceptance Sampling and Testing of Bituminous Mixture (Compaction). The compaction of the mixture will be accepted in lots. Lot size will be as defined in subsection 401.21. The mean and range of the density of the pavement will be calculated from the results of all tests run on randomly selected sites. Acceptance will be in accordance with Table 401.3. In addition to the tests which are run on randomly selected sites, the Engineer reserves the right to test any area which appears defective and to require the specified compaction. 401.23 Acceptance Sampling and Testing of Bituminous Mixtures (Surface Tolerance). The surface will be checked by use of a 10-foot straightedge at sites selected by the Engineer. The straightedge will be applied at right angles and parallel, respectively, to the centerline of the roadbed.

The variation of the surface from the testing edge of the straightedge between any two contacts with the surface shall not exceed one-fourth inch.

Tests will be made immediately after initial compaction and any variations detected shall be corrected by removing or adding materials, as may be necessary. Rolling shall then be continued as specified. After final rolling, the smoothness of the course shall be checked again and any area defective in texture or composition shall be corrected, including removal and replacement of unsatisfactory material at the Contractor's expense, as directed by the Engi

neer.

401.24 Acceptance Sampling and Testing of Bituminous Materials. Acceptance of bituminous material will be in accordance with subsection 702.04, Bituminous Materials. The Contractor shall provide a suitable unloading area at the project plant site for use by transport trucks that will assure complete drainage of the tanks while the material is still fluid.

Method of Measurement

401.25 Bituminous mixtures will be measured by the ton or square yard, as shown in the bid schedule.

When measurement is by the ton, batch weights will not be permitted as a method of measurement, unless provisions of paragraph 3 of AASHTO M156 are met, in which case the cumulative weight of all batches will be used for payment. The tonnage will be the weight used in the accepted pavement and no deduction will be made for the weight of bituminous material in the mixture.

When measurement is by the square yard, the longitudinal and transverse measurements will be determined in accordance with subsection 109.02.

Basis of Payment

401.26 The accepted quantities of bituminous mixture, determined as provided above, will be paid for at the contract unit price per unit of measurement, respectively, for each of the particular pay items listed under the applicable Section and shown in the bid schedule. These prices and payments shall be full compensation for furnishing and placing all materials, including all labor, equipment, tools, and incidentals necessary to complete the work prescribed in this Section.

When any pay factor for a lot of bituminous mixture is less than 1.0, as determined in subsections 401.21 or 401.22, payment for the material in that lot will be made at a reduced price arrived at by multiplying the contract unit price for the bituminous mixture by the lowest single pay factor. In no case, however, will the reduced price be less than 70 percent of the contract unit price for any material allowed to remain in place.

TABLE 401-1

Allowable Deviations from Target Values for Bitumen Content and Gradation

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D - The allowable deviation in percent from the target values.

- The difference between the highest and lowest values of the test results from a given lot. Arithmetic mean or average of individual test results for a lot.

R- (Range)

Mean

A lot must meet criteria for both the deviation of the mean and the maximum allowable range at a given pay level for the aggregates and bitumen content.

Only the lowest single pay factor for bitumen content and aggregate gradation, as determined from the table above, will be used in computing reduced payment for the lot.

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R(Range) The difference between the highest and lowest values of the test results from a given lot.

Mean Arithmetic mean or average of individual test results for a lot.

Section 402.-OPEN-GRADED ASPHALT CONCRETE FRICTION

COURSE

Description

402.01 This work shall consist of constructing a surface course on a foundation in accordance with these specifications and in reasonably close conformity with the lines, grades, thicknesses and typical cross sections shown on the plans or established by the Engineer.

Materials

402.02 Composition of Mixture. The bituminous mixture shall be composed of a mixture of aggregate and bituminous material. The amount of bituminous material shall be between 6 and 9 percent by weight of the total mixture, adjusted to reflect variations in aggregate densities.

Prior to producing the bituminous mixture, the Contractor shall submit in writing the proportion of each type of aggregate that he proposes to use, as well as, a job-mix formula proposing definite single values for:

(a) The percentage of aggregate passing each specified sieve.

(b) The percentage of bituminous material to be added based on total weight of mix. (c) The temperature of the mixture leaving the mixer.

(d) The temperature of the mixture delivered on the road.

(e) The kind and percentage of any additives to be used.

The Engineer will evaluate the proposed job mix formula and make any adjustments in it as determined necessary to meet specified design criteria. The Engineer will establish the job mix formula with single values for (a) through (e) above, and will approve the job mix formula so notifying the Contractor in writing. The mixture furnished by the Contractor shall conform to this job-mix formula.

The mixture shall have an index of retained strength (AASHTO T 165) of not less than 50 percent.

When unsatisfactory results or a change in materials sources make it necessary, the Engineer may establish a new job-mix formula. Should a change in sources of materials be proposed, a new job-mix formula will be established before the new material is used.

402.03 Aggregates. Aggregates shall meet the applicable requirements of subsections 703.07 and 703.09.

402.04 Bituminous Materials. Bituminous material shall be AC 20 meeting the requirements of subsection 702.01.

Construction Requirements

402.05 Weather Limitations. The weather limitations shall be as specified in subsection 401.11, supplemented to require that the surface temperature shall be at least 60°F.

402.06 Bituminous Mixing Plant. The plant shall meet the applicable portions of subsection 401.07.

402.07 Hauling, Placing and Compacting Equipment. Equipment shall meet the applicable requirements of subsection 401.08, 401.09, and 401.10, except than 401.10 is amended to require steel wheel rollers conforming to section 212.02(2).

402.08 Conditioning of Existing Surface. Immediately before placing the bituminous mixture, the existing surface shall be cleaned of loose or deleterious material by brooming or other approved means.

Contact surfaces of curbing, gutters, manholes and other structures shall be painted with a thin, uniform coating of bituminous material prior to the bituminous mixture being placed against them.

402.09 Preparation of Materials. Materials shall be prepared in accordance with subsection 401.13 and 401.14 and mixed in accordance with subsection 401.15, with the following exception:

(1) The aggregates shall be prepared in accordance with 401.14, except the temperature of the aggregates shall not exceed that at which the asphalt cement has a kinematic viscosity of 800 centistokes.

402.10 Transporting, Spreading and Finishing. The bituminous mixture shall be transported, spread and finished in accordance with subsection 401.17.

402.11 Compaction. After the bituminous mixture has been spread, struck off, and surface irregularities adjusted, it shall be thoroughly and uniformly compacted by rolling. The bituminous mixture shall be rolled in a longitudinal direction, commencing at the outside edge and progressing towards the center. Rolling shall be accomplished with a steel-wheel roller and shall be conducted in such a manner that shoving, distortion, or stripping will not develop beneath the roller. On superelevated curves, the rolling shall commence on the low side and progress to the high side. The amount of rolling shall be confined to only that necessary for consolidating the bituminous mixture and bonding it to the underlying surface. Excessive rolling shall be avoided.

The completed bituminous mixture shall be protected from all traffic until it has set up and sufficiently hardened to resist abrasion.

402.12 Acceptance Sampling and Testing. Sampling and testing will be performed in accordance with subsection 401.21, 401.22, 401.23, and 401.24 as appropriate.

Method of Measurement

402.13 The bituminous mixture shall be measured in accordance with subsection 401.25.

Basis of Payment

402.14 The accepted quantities of the bituminous mixture determined as provided above will be paid for at the contract price, except that pay factors will be applied to the contract unit price in accordance with subsection 401.26, complete in place, which price and payment will be full compensation for all materials furnished and all work performed under this Section.

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403.01 This work shall consist of constructing one or more courses of bituminous pavement on a prepared base in accordance with these specifications, and in reasonably close conformity with the lines, grades, thicknesses and typical cross sections shown on the plans or established by the Engineer.

The bituminous pavement shall be composed of a mixture of aggregate and bituminous material of the type shown in the bid schedule.

Materials

403.02 General. The materials and their use shall conform to the requirements of subsections 401.02 through 401.06.

The percentage range by weight of bituminous material to be added will be shown in the special provisions. Aggregate shall meet the requirements of subsection 703.09 for the grading called for in the bid schedule.

Construction Requirements

403.03 General. The construction requirements shall be as prescribed in subsections 401.07 through 401.20.

Method of Measurement

403.04 Hot bituminous pavement will be measured as prescribed in subsection 401.25.

Basis of Payment

403.05 The accepted quantities of hot bituminous pavement determined as provided above will be paid for at the contract price, except that pay factors will be applied to the contract unit price in accordance with subsection 401.26, for the bituminous mixture and per ton or per gallon for the bituminous material, when specified, complete in place, which price and payment will be full compensation for the work of this Section.

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404.01 Description. This work shall consist of constructing one or more courses of cold bituminous mixture on a prepared base in accordance with these specifications and in reasonably close conformity with the established lines, grades, thicknesses and typical cross sections shown on the plans or established by the Engineer.

The bituminous pavement shall be composed of a mixture of aggregate and liquid bituminous material; and, if specified, a top dressing of sand, stone or slag screenings.

Materials

404.02 General. The materials and their use shall conform to the requirements of subsections 401.02 through 401.06.

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