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.

Payment will be made under:

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.

Subsection 401.03 is supplemented as follows:

(a) Liquid asphalts shall conform to subsection 702.02.

(b) Emulsified asphalts shall conform to subsection 702.03. (c) Tars shall conform to subsection 702.08.

The material for top dressing shall meet the requirements of subs tion 703.10(b).

Construction Requirements

404.03 General. The construction requirements shall be as p scribed in subsections 401.07 through 401.24, with the following mod cations:

(a) When combined with bituminous materials other than emulsif asphalt, the aggregate shall be dry and at a temperature of not le than 60° F (15 t° c), nor more than 225° F (107 t° c). If not alrea surface dry, the aggregate shall be dried at a temperature of from 1 F (66 t° c) to 300° F (149 t° c), then cooled before being mixed with t bituminous material.

(b) When combined with emulsified asphalt, the aggregate shall at a temperature of not less than 60° F (15 t° c) nor more than 175° F to c).

(c) The aggregate, prepared as prescribed above, shall be combin in the amounts required to meet the job-mix formula, introduced in the mixer and mixed dry for a period sufficient to distribute the vario sizes uniformly throughout the batch. The bituminous material, in tl proper proportion, shall then be introduced into the batch and mixe until the aggregates are thoroughly coated and the mass is a unifor color.

The mixing time for each phase of the mixing operation shall be set b the Engineer as determined from the nature of the aggregates, tl job-mix formula and the size of the batch, but in no case shall t mixing time, after the introduction of the bituminous material, be le than 2 minutes.

(d) When a top dressing of aggregate is specified it shall be applie immediately after the rolling of the surface course. The top dressin shall be evenly applied at the rate specified and rolled as directed.

404.04 Method of Measurement. Cold bituminous pavement wi be measured as prescribed in subsection 401.25.

404.05 Basis of Payment. The accepted quantities of col bituminous pavement will be paid for at the contract price per ton fo the bituminous paving mixture and the aggregate top dressing and pe ton or gallon for the bituminous material complete in place. Payment will be made under:

Pay Item

404(1) Cold Bituminous Pavement..

Pay Unit

Ton.

405.01 This work shall consist of constructing one or more courses of road mix bituminous pavement on a prepared base or road surface 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.

405.02

Materials

Bituminous Material. The bituminous material shall be of the type and grade called for in the bid schedule and shall conform to the following subsections:

Application temperatures of bituminous materials shall conform to subsection 702.05.

405.03 Aggregate. The aggregate will be tested for acceptance immediately preceding addition of bituminous material to the mix. This acceptance will be based on periodic samples of the windrow after all aggregates have been blended for each layer.

(a) Case 1 (new aggregate).-New aggregate shall conform to subsection 703.09, for grading F of table 703-4.

(b) Case 2 (aggregate salvaged from the existing surface).-Where aggregate required for the road mix surface course is already in place, the Contractor shall not be responsible for its grading or quality except

for removal of oversize pieces. In general, salvaged aggregate to be used for road mix surface course will consist of material meeting the requirements given above for new aggregate or may consist of selected granular material for other gradings. Any particles of salvaged aggregate appearing in the surface at the time of lay-down and finishing that will not pass a 12-inch (37.5 mm) sieve shall be removed by the Contractor as directed by the Engineer.

Construction Requirements

405.04 Weather Limitations. The construction of road mix bituminous pavement shall be carried on only when the surface on which the material is to be placed in dry and when the surface temperature is above 50° F (10 t° c).

405.05 Equipment. The equipment used by the Contractor shall include scarifying, mixing, spreading, finishing and compacting equipment; a bituminous distributor; and equipment for heating bituminous material.

The distributor shall be so designed, equipped, maintained and operated that bituminous material at even heat may be applied uniformly on variable widths of surface up to 15 feet (4.57 m) at readily determined and controlled rates from 0.05 to 2.0 gallons (0.189 to 7.57 dm3) per square yard, (0.836 m2), with uniform pressure, and with an allowable variation from any specified rate not to exceed 0.02 gallons (0.0757 dm3) per square yard (0.836 m2). Distributor equipment shall include a tachometer, pressure gauges, accurate volume measuring devices or a calibrated tank, and a thermometer for measuring temperatures of tank contents. Distributors shall be equipped with a power unit for the pump, and full circulation spray bars adjustable laterally and vertically. Traveling or stationary mixing plants or other equipment of proven performance may be used by the Contractor in lieu of the specified equipment if approved.

Rollers shall be self-propelled steel-wheel tandem or 3-wheel rollers weighing not less than 8 tons (7.257 tonnes) each, and pneumatic-tire rollers having a total compacting width of not less than 60 inches (1.52 m) and the gross weight adjustable within the range of 200 to 350 pounds (90.7 to 158.8 kg) per inch (25.4 mm) of compaction width. The operating weight shall be as directed. Contact pressure may be specified for pneumatic-tire rollers. All tires on pneumatic rollers shall be equally inflated, exerting equal unit pressure, with a means of varying the contact pressure to suit project conditions.

405.06 Preparation of Base. (a) Case 1 (new aggregate).-When new aggregate is to be used for the road mix surface course, the existing base shall be scarified lightly and bladed to uniform grade and to the cross section shown on the plans and shall then be rolled, or watered and rolled, as directed. If so ordered by the Engineer, depressions shall first be filled and weak portions of the base strengthened with new aggregate.

(b) Case 2 (salvaged aggregate).-When material in the existing road surface is to be used for mixing, the surface shall first be scarified lightly and bladed to uniform grade and to the cross section shown on the plans. The reshaped surface shall then be scarified again to the depth ordered by the Engineer and in such manner as to leave a foundation of undisturbed material parallel, both in profile and cross section, to the proposed finished surface. The loosened material shall be bladed aside into a windrow at the side of the road, and the undisturbed material rolled, or watered and rolled, as directed.

405.07 Placing Aggregates. New aggregates, where required, shall be uniformly spread on the prepared surface by the use of spreader boxes, or other approved mechanical spreading devices. When two or more sizes of aggregates are used, each size of aggregate shall be placed in the proper amount to provide for surfacing of the required width and thickness. The proper amounts of the separate sizes of aggregate for each course shall be blended and shaped into a windrow of uniform cross section. At least one day shall then be allowed for measuring, sampling, and testing for approval of quantity and gradation before the windrow is spread for application of bituminous material.

If the surface moisture of the aggregate is more than 2 per cent of the dry weight of the aggregate, except when the bituminous material is emulsified asphalt, the aggregate shall be turned by blades or disc harrows or otherwise aerated until the moisture content is reduced to 2 per cent or less. The aggregate shall then be spread smoothly and uniformly over half the road or other convenient width of the surface ready for the application of bituminous material, except that when a traveling mixing plant is used the aggregate shall be formed into a uniform cross section.

In lieu of aerating and drying the aggregate, the Contractor may use an approved additive, except where emulsified asphalt is used, which shall be satisfactorily blended with the bituminous material. The additive shall permit suitable coating of the wet aggregate and shall prevent the bituminous coating from stripping in the presence of water. 405.08 Application of Bituminous Material. The bituminous material shall be uniformly distributed in successive applications, in such amounts and at such intervals as directed. The mixing equipment shall follow immediately behind the distributor, after each application of bituminous material, to partially mix the aggregate and the bituminous material.

405.09 Mixing. After the last application of bituminous material and partial mixing, the entire mass of bituminous material and aggregate shall be windrowed on the road surface and then mixed, by blading the mixture from side to side of the road, or by manipulations producing equivalent results, until all aggregate particles are coated with bituminous material and the whole mass has a uniform color and the mixture is free from fat or lean spots, balls or uncoated particles. During the mixing operations, care shall be taken to avoid cutting into