417.01 This work shall consist of constructing a bituminous plant mix surfacing course on a prepared base in accordance with these specifications and in reasonable close conformity with the lines grades, thicknesses and typical cross section shown on the plans or established by the Engineer.

Materials

417.02 (a) Composition of the Mix. The bituminous plant mix surfacing shall be composed of a mixture of aggregate, chemical additives if required by the job mix formula, and bituminous material of the type shown in the bid schedule.

(b) Job Mix Formula. After a representative quantity of aggregate has been produced and not less than 10 days before production of plant mix surfacing beings, the contractor shall submit to the engineer his proposed job mix formula. Representative samples shall than be taken of the stockpiled material and the final job mix formula established by the engineer based upon a standard laboratory design procedure. The mixture is expected to exhibit a minimum dry compressive strength of 200 psi (1.379 MPa), and a minimum 70% retained strength when tested in accordance with AASHTO T 165.

The job mix formula shall include definite single values for:

(a) The percentage of aggregate passing each specified sieve, based on the dry weight of the aggregate.

(b) The percentage of bituminous material to be added, based on
the total wieght of the mixture.

(c) Kind and amount of chemical additives (anti-stripping, hy-
drated lime, etc.) as established by the design procedure.
(d) Maximum Theoretical Density.

Should a change in sources of material be found necessary or the job mix formula be found unsatisfactory a new job mix formula will be established.

417.03 The materials and their use shall conform to the requirements of 401.03 through 401.06.

The percentage range by weight of bituminous material to be added is normally expected to be from 4 to 7 percent. Aggregate shall meet the requirements of subsection 703.09 for the grading shown in the bid schedule.

Construction Requirements

417.04 General construction requirements shall be as prescribed in subsection 401.07 through 401.24.

Method Of Measurement

417.05 Bituminous Plant Mix Surfacing will be measured as prescribed in subsection 401.25

Basis of Payment

417.06 The accepted quantities of bituminous plant mix surfacing determined as provided above will be paid for at the contract price per ton for the bituminous mixture and per ton for the bituminous material, except that pay factors will be applied to the contract unit price in accordance with subsection 401.26, completed in place, which price and payment will be full compensation for the work of this section. Payment will be made under:

Section 500

RIGID PAVEMENT

Section 501.-PORTLAND CEMENT CONCRETE PAVEMENT

Description

501.01 This work shall consist of constructing a pavement composed of air-entrained portland cement concrete, with or without reinforcement as specified, constructed 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.

501.03 Quality of Concrete; Proportioning. The proportioning of water, cement, and aggregates will be based on predetermined cement content, unless the special provisions require the substitution of proportions designed for minimum strength.

(a) Mix based on predetermined cement content.-The proportions shown in table 501-1 are designed to produce concrete containing 564 pounds (255.8 kg) of cement plus or minus 2 percent per cubic yard, suitable for normal machine placement and having an air content within the limits specified and a slump of 11⁄2 to 3 inches (38 to 76 mm) for nonvibrated concrete. The weights are saturated surface-dry weights. The percentage of air entrained in the mix shall be 6 percent plus or minus 11⁄2 percent.

Table 501-1.-Approximate proportions for air-entrained portland cement concrete of specified cement content and slump

Table 501-1 is based on the assumption that the saturated surfacedry bulk specific gravity of sand, gravel, and stone is 2.65 and that of slag is 2.25; that the sand is well graded and has a fineness modulus between 2.6 and 2.9; and that the coarse aggregate is composed of about 60 percent of the larger separated component and about 40 percent of the smaller separated component, when separated at the 34-inch (19.0 mm) sieve for the 12-inch (37.5 mm) to No. 4 size, or at the 1-inch (25.0 mm) sieve for the 2-inch (50.0 mm) to No. 4 (4.75 mm) size. Bulk specific gravity will be determined by using AASHTO T 84 or T 85, the slump using AASHTO T 119, and the air content using AASHTO T 152 for sand, gravel, and stone and ASTM C 173 for slag. For batching, the quantities given in table 501-1 will be adjusted by the Engineer for differences in specific gravity in order to obtain the desired workability and slump, for the specified cement content, and for the free moisture content of the aggregates being used. The total weight of aggregates per 94 pounds (42.6 kg) of cement shall not be varied except to compensate for variations in specific gravity and/or moisture content.

(b) Mix based on minimum flexural or compressive strength.-If the special provisions stipulate that the proportions of cement, fine aggregate, coarse aggregate, and water to be used in the mix are to be based on design for minimum strength rather than on predetermined cement content, the Engineer will determine, from laboratory tests of the materials to be used, the nominal cement content and the proportions that will produce a workable concrete having a slump of between 12 and 3 inches (38 and 76 mm) if not vibrated (or between 2 and 2 inches (13 and 51 mm) if vibrated) and a flexural strength of not less than 550 pounds per square inch (3.792 MPa) when tested in accordance