2008-213 (5) - Laserfiche WebLink

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B. Soil Stability and Compaction Control The Contractor shall arrange to have sufficient soil tests made by an independent testing laboratory selected by the Engineer to demonstrate conformance of his work with the stability and compaction levels required by these specifications. Compaction tests shall be taken at intervals listed herein or as deemed necessary by the Engineer. Any proposed alternative test methods to those specified herein must be approved by the Engineer prior to testing. At the request of the Engineer, the Contractor shall provide such documentation of a proposed alternative test method as the Engineer may require to evaluate the method for approval. In no case shall the Contractor proceed with construction on compacted material until the tests prove satisfactory and approval is given by the Engineer. In general, at least one test for maximum dry density/optimum moisture content shall be performed on a representative sample of each inherently different material to be used for compacted backfill or embankment fill. For material of uniform composition and textural class, a minimum of one test per 200 cu. yd. of material shall be performed at the point of use. Tests for in-place density (percent compaction) shall be taken at locations designated by the Engineer. The Contractor shall have density tests taken in four (4) separate locations. Each location shall be tested in lifts not to exceed 12 -inches in thickness. E. Trench Backfilling Backfill as rapidly as construction, testing, and acceptance of work permits. Place and compact backfill under structures and paved areas in 12 inch lifts to top of trench and in 6 inch lifts to one foot over pipe outside structures and paved areas. 1. Bedding Requirements Except as specified otherwise in the individual piping section, provide bedding for buried piping in accordance with AWWA C600, Type 4, except as specified herein. Backfill to top of pipe shall be compacted to 95 percent of ASTM D 698 maximum density. Plastic piping shall have bedding to spring line of pipe. Provide ASTM D 2321 materials as follows: Class I: Angular, 0.25 to 1.5 inches, graded stone, including a number of fill materials that have regional significance such as coral, slag, cinders, crushed stone, and crushed shells. Class 11: Coarse sands and gravels with maximum particle size of 1.5 inches, including various graded sands and gravels containing small percentages of fines, generally granular and noncohesive, either wet or dry. Soil Types GW, GP, SW, and SP are included in this class as specified in ASTM D 2487, 3.05 COMPACTION Expressed as a percentage of maximum density. Determine in-place density of existing subgrade; if required density exists, no compaction of existing subgrade will be required. 02302 = 7 02302 - Excavation and Fill