Basis of Payment 405.13 The accepted quantities of road mix bituminous pavement determined as provided above will be paid for at the contract price per specified unit for all construction, aggregates, and bituminous material complete in place which price and payment will be full compensation for the work of this section. Letter suffixes will be added to pay item number 405 (4) to designate alternative types of material to be bid on. Ton. Section 406.—PENETRATION MACADAM Description 406.01 This work shall consist of furnishing and placing one or more courses of graded coarse aggregate and one or more applications of bituminous binder, with a bituminous seal coat and chip covering, constructed on a prepared base course by the penetration method in accordance with these specifications and in reasonably close conformity with the lines, grades, thicknesses and typical cross section shown on the plan or established by the Engineer. Quantities of Materials Per Square Yard. The approximate quantities of materials per square yard and the sequence of applications and spreadings shall meet the require ments given in table 406-1 for the designation called for in the bid schedule. Table 406-1.-Quantities per square yard1 (using emulsified asphalt, asphalt cement, or tar) for bituminous 1 This table indicates spreading of aggregates in cubic yards per square yard (truck measure) and bituminous materials in gallons per square yard (at normal application temperatures). Materials 406.02 Bituminous Materials. The type and grade of bituminous material will be specified in the contract. The grade may be changed one step by the Engineer during construction at no change in unit price. Bituminous material may be conditionally accepted at the source, subject to the provisions of clause 10 of the General Provisions. 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. 406.03 Aggregates. Aggregates shall meet the requirements of subsection 703.12. The aggregate may be accepted in stockpile at the source, subject to the provisions of clause 10 of the General Provisions. Construction Requirements 406.04 Weather Limitations. Application of bituminous material shall be made only when the aggregate is dry, when the atmospheric temperature in the shade is above 55° F. and rising or above 60° F. if falling, and when the weather is not foggy or rainy. 406.05 Equipment. The equipment to be used shall include a power broom and a power blower, approved broom dragging equipment, rollers, a self-propelled mechanical spreader for spreading coarse aggregate, a mechanical revolving cylindertype aggregate spreader or mechanical roller-type hopper spreader for spreading fine aggregate that can be so adjusted as to spread accurately the required amount of material per square yard, a bituminous distributor meeting the requirements of subsection 405.05, and equipment for heating bituminous material. Other types of aggregate spreaders may be used provided they accomplish results equal to those obtained by the types described herein, and are approved. Rollers shall be self-propelled steel wheel, vibratory or pneumatic type. The number and weight of rollers shall be sufficient to compact the mixture to the required condition. 406.06 Placing and Compacting Coarse Aggregate. The number of courses in which the penetration macadam is to be constructed and the order in which and rates at which the bituminous materials and mineral aggregates are to be spread, shall be as indicated in table 406-1. The initial spreading of aggregate in each layer shall immediately follow the application of bituminous material, except where the first spreading is required to be placed directly on a previously bituminized surface. Immediately before placing the pavement courses, the acceptably prepared base upon which the pavement is to be constructed shall be swept clean. Coarse aggregate shall be placed in the required amount by approved stone spreaders, or by other approved mechanical methods. All areas of nonuniformly graded aggregate shall be removed and replaced with suitable material before the rolling begins. These corrections shall be made by hand picking whenever necessary and shall be continued after initial rolling until the appearance and texture of the aggregate are uniform and all irregularities are corrected. The coarse aggregate shall be dry rolled until the aggregate is compacted and keyed. Rolling shall be parallel to the road center line and shall start at the outer edges of the road, overlap equal portions of aggregate and shoulder, and progress toward the center, overlapping on successive passes by at least one-half the width of the roller, except that on superelevated curves rolling shall progress from the lower to the upper edge. Rolling shall continue until the aggregate does not creep or wave ahead of the roller. Material which crushes excessively under the roller or becomes segregated in such manner as to prevent free and uniform penetration of the bituminous material shall be removed and replaced with suitable aggregate, without additional compensation. The compacted coarse aggregate shall have a firm, even surface. Along curbs, headers and walls, and at all places not accessible to the roller, the aggregate shall be tamped thoroughly with mechanical tampers or with hand tampers. Each hand tamper shall weigh not less than 50 pounds and have a face area of not more than 100 square inches. Aggregate in any course that becomes coated or mixed with dirt or clay prior to the application of the bituminous material shall be removed and replaced with clean aggregate, and the area shall be re-rolled. Dry rolling shall be stopped when the surface of the coarse aggregate will support the distributor and before the voids are closed sufficiently to prevent the free uniform penetration of the bituminous material. Prior to application of the bituminous material, the surface of the aggregate will be tested by the Engineer using a 10-foot straightedge at selected locations. The variation of the surface from the testing edge of the straightedge between any 2 contacts with the surface shall at no point exceed -inch. All humps or depressions exceeding the specified tolerance shall be corrected by removing defective work and replacing it with new material as specified. Each course of aggregate shall be spread so that the bituminous material is covered before wheels or tracks pass over it. 406.07 Application of Bituminous Material. Bituminous material shall be uniformly applied at the rate specified in table 406-1 for the pavement designation shown in the bid schedule. Building paper shall be placed over the end of the previous applications and the joining application shall start on the building paper. Building paper so used shall be removed and disposed of in a satisfactory manner. During the application of bituminous material care shall be taken to prevent spattering adjacent pavements, structures and trees. The distributor shall not be cleaned or discharged into ditches, borrow pits, on shoulders or along the right-of-way. 406.08 Seal Coats. For mats requiring two seal coats, a period of at least 4 days shall elapse between the placing of the first seal coat and cover and the placing of the second seal coat, during which period the surface shall be opened to traffic and maintained by the Contractor by brooming and rolling. 406.09 Finishing. The Contractor shall broom, roll, and maintain the final seal coat, or final application in case of ATE 36, for a period of 3 days following the placing of all materials, as directed by the Engineer. Method of Measurement 406.10 Aggregate and bituminous material will be measured by the units shown in the bid schedule. When slag and stone (or gravel) are designated as alternative materials for pay items in the bid schedule and payment is by weight, the estimated quantities will be based on assumed average bulk specific gravities of available alternative materials. No adjustment in contract unit price will be made for variation in quantity due to differences in the specific gravity of the material actually used. Basis of Payment 406.11 The accepted quantities of pay items from the list below that appear in the bid schedule, determined as provided above, will be paid for at the designated contract price per pay unit, which price and payment will be full compensation for the work of this section. Payment will be made under: |