Laserfiche WebLink
13-07 <br /> <br />of the Engineer. Materials used for backfill must be free from roots, <br />rubbish, decayed, vegetable or other organic matter, fragments of <br />pavements or sidewalks and all other objectionable materials. <br />Backfill over and around pipe and str~ctures shall be brought u~p <br />uniformly on all sides in order to avoid bending or distortional <br />stresses. <br /> <br />a. Class IA Compacted backfill, shall be placed in horizontal layers <br /> not exceeding eight inches (8") in depth before compaction. Each <br /> layer shall be moistened as directed by the Engineer and <br /> thoroughly tamped by pneumatic tampers, there being not less than <br /> one tamper to each shoveler. The relative compaction shall not be <br /> less than ninety percent (90%) as determined by the latest <br /> revision of Test Method No. California 216 of the Department of <br /> Transportation of the State of California. <br /> <br /> Materials for backfilling shall be as specified or shown on the <br /> drawings or as directed by the Engineer and shall be located <br /> within the cross-section as indicated on the drawings. <br /> <br /> , shall be placed in horizontal layers <br />b. Class IB Compacted backfill(8,, <br /> not exceeding eight inches ) in depth before compaction. Each <br /> layer shall be moistened as directed by the Engineer and <br /> thoroughly tamped, rolled or otherwise compacted until the <br /> relative compaction is not less than ninety percent (90%) as <br /> determined by the latest rfevision of Test Method No. California <br /> 216 of the Department of Transportation of the State of <br /> California. Should the Contractor elect to furnish sandy or <br /> granular material for backfill, the eight inch layer construction <br /> may be eliminated and compaction obtained by jetting. Jetting <br /> will not be permitted when the backfill material will not compact <br /> to a relative compaction of ninety percent (90%) by such methods, <br /> nor where the foundation material.is such that it will soften when <br /> saturated. Where jetting is used, the jets shall be of sufficient <br /> length to reach the bottom of each layer; the water supply shall <br /> be continuous; the material jetted shall be free of stones or <br /> lumps exceeding four inches (4") in greatest dimension, and the <br /> material shall have a sand equivalent value of not less than 20. <br /> Materials for backfilling shall be as specified or shown on the <br /> drawings or as directed by the Engineer and shall be located <br /> within the cross-section as indicated on the drawings. Where <br /> jettig of sandy or granular materials will not result in the <br /> compaction specified-above, the Contractor shall substitute a <br /> vibratory method of compaction which will give the specified <br /> results. <br /> <br /> Backfill for 72" Pipe. The backfill material for the 72" storm drain <br /> li'ne shall be "Fine Fill" meeting the requirements of the City of <br /> Pleasanton in accordance with the City Standard Trench Backfill Detail. <br /> <br />CDS.1.12 13-3 <br /> <br /> <br />