1925 (#1403-1607) - Laserfiche WebLink

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the rolling and floating process, it shall be belted over with a combined crosswise and longitudinal motion, using long vigorous crosswise strokes of the belt. At this belting the longitudinal motion shall be slight, but it may be ncreased in succeeding beltings. Care shall be taken not to work the crown out of the pavement nor to permit the edges of the belt to dig into the surface of the concrete. Just before the concrete obtains its initial set and after the water glaze or sheen disappears, the surface shall be given a final belting to produce a uniiorm surface of gritty texture. This belting shall be done by using short rapid tronsverse strokes with a sweeping longitudinal motion. The surface shall be belted as many times as required to produce the above described result, but in no case shall it be belted less than three (3) times. Badly worn belts must not be used. (e) After the final belting, ail exposed edges of the pavement and all expansion joints, and along all header lines, the edge shall be rounded off with a one-hal/ (~) inch radius edging tool. A split float, having a length of not less than seven (7) feet, shall be used on all expansion joints. When noted on the plans the concrete pavement shall be mechanically tamped and leveled off with a machine of approved design. The mechanical tamper shall go over each area of the pavement at least five (5) times and at such intervals as will produce results as above specified, and shall then be rolled, floated and belted as hereinbefore described. SECTION 7. JOINTS AND FILLERS, !~xpansion joints shall be constructed when shown or otherwise indicated on the plans. The filler /or the expansion joints shall consist ot prepared strips of bitumen, or fibre matrix and bitumen, or similar material of approved quality, and shall be three-fourths (~) inch in thickness and the width shall be at least one and one-half (IX) inches greater than the thickness of the pavement. The joint filler shall be placed in a vertical position and at right angles to the center llne of the street. On completion of the pavement, the lower edge of the filler shall be in contact with the subgrade /or its entire length. The joint filler shall be supported by a well staked steel or wooden bulkhead or header of sufficient strength to hold the same in a vertical position as well as in a straight line until the concrete has been placed and tamped, after which the bulkhead or header shall be removed and the space carefully filled with additional concrete and thoroughly tamped. The contractor shall use extreme care in the placing of expansion joint fillers to pre- vent damaging them during the placing, tamping and finishing oi the concrete. Belore the pavement is opened to traffic, all expansion joint fillers shall be trimmed /tush with the surface of the pavement. 8RCTION S~ EXPANSION JOINT SUPPORTS. l~xponsion joint supports shall be constructed only when indicated on the plans, and shall be of thc dimensions as shown in dctell on the plans. These supports must be built ot the same mixture of concrete as the pavement and their upper surface shall be finished smoothly with a steel trowel and flush with the sub-base. They shall be cured by covering with damp sand or earth for at least five ($) days, and ptanked or otherwise protected when crossed by trucks, wagons, mixer or other equipment. SECTION 9. pLAIN CONSTRUCTION JOINTS. All construction or contracting joints will be plain joints unless otherwise noted on the plans. They shall consist of longitudinal joints along the center llne of the pavement, wbon shown on plans; and where expansion joints are not used, all transverse jo/nts shown