Laserfiche WebLink
installation , shall be kept clean until they are used in the work and <br /> when laid , shall conform to the lines and grades required . <br /> Q . As soon as the excavation is complete to normal grade of the <br /> bottom of the trench , bedding shall be placed , compacted and <br /> graded to provide firm , uniform and continuous support for the <br /> pipe . Bell holes shall be excavated so that only the barrel of the <br /> pipe bears upon the bedding . The pipe shall be laid accurately to <br /> the lines and grades indicated on the Drawings . Blocking under <br /> the pipe will not be permitted . Bedding shall be placed evenly on <br /> each side of the pipe to mid -diameter and hand tools shall be <br /> used to force the bedding under the haunches of the pipe and into <br /> the bell holes to give firm continuous support for the pipe . <br /> Bedding shall then be placed to 12-in above the top of the pipe . <br /> The initial 3-ft of backfill above the bedding shall be placed in 1 -ft <br /> layers and carefully compacted . Generally the compaction shall <br /> be done evenly on each side of the pipe and compaction <br /> equipment shall not be operated directly over the pipe until <br /> sufficient backfill has been placed to ensure that such compaction <br /> equipment will not have a damaging effect on the pipe . The pipe <br /> manufacturer's representative prior to use shall approve <br /> equipment used in compacting the initial 3-ft of backfill . <br /> R. Good alignment shall be preserved during installation . The <br /> deflection at joints shall not exceed that recommended by <br /> manufacturer. Fittings , in addition to those shown on the <br /> Drawings , shall be provided , if required , in crossing of utilities that <br /> may be encountered upon opening the trench . <br /> S . Each length of the pipe shall have the assembly mark aligned with <br /> the pipe previously laid and held securely until enough backfill has <br /> been placed to hold the pipe in place . Joints shall not be " pulled" <br /> or "cramped . " <br /> T. Before any joint is made , the pipe shall be checked- to assure that <br /> a close joint with the next adjoining pipe has been maintained and <br /> that the inverts are matched and conform to the required grade . <br /> The pipe shall not be driven down to grade by striking it. <br /> U . Precautions shall be taken to prevent flotation of the pipe in the <br /> trench . <br /> V . When moveable trench bracing such as trench boxes , moveable <br /> sheeting , shoring or plates are used to support the sides of the <br /> trench , care shall be used in placing and moving the boxes or <br /> supporting bracing to prevent movement of the pipe , or <br /> disturbance of the pipe bedding and the backfill . Trench boxes , <br /> moveable sheeting , shoring or plates shall not be allowed to <br /> extend below the top of the pipe . As trench boxes , moveable <br /> sheeting , shoring or plates are moved , pipe bedding shall be <br /> 3 - 8 <br />