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ivtoisture-Density Relationsh~ Samples of the soils and bedrock were remolded in accordance with • <br />ASTM D-598 to determine the standard Proctor values. The test is run [o determine the maximum <br />remolded dry density and optimum moisture content of a sample compacted in 3 lifts in a steel mold, <br />with a 5.5-pound hammer falling 12 inches. The Proctor test results aze shown in Figures #19 thru <br />#24. <br />Triaxial Shear/ComRession Tests: Triaxial shear testing was performed on relatively undisturbed and <br />remolded soil samples. The test consisted of subject a cylindrical specimen to an all-around pressure <br />and an axial load varied independently of the all-around pressure. The all-around pressure was applied <br />in a Iluid-filled chamber and the axial load was applied by means of a piston passing through the <br />chamber top. <br />Porous disc were placed against the bottom of the sample which was wrapped in a watertight <br />membrane and the discs were corrected to the outside of the chamber by tubing. The water pressure <br />in the pores of the sample can be measured through these tubes when drainage from the sample is no[ <br />permitted. When flow is permitted the quantity of water passing into or out of the sample upon <br />loading can be measured. <br />Consolidated, undrained triaxial shear testing was performed on selected samples. The samples were <br />saturated and the chamber pressure raised incrementally. The samples were allowed [o consolidate <br />under the applied chamber pressure until no excess pore pressure remained. Valves on [he porous • <br />tubes were then closed and axial load was applied to the sample. The axial svess and strain within the <br />sample were measured as the axial load was increased to failure. The consolidated, undrained test is <br />called the R-test. The rate of strain selected was based on an estimate of the consolidation <br />characteristics of the material. <br />Effective svesses can be obtained from unconsolidated, undrained triaxial testing by measuring the <br />pore pressures in the sample and subvacting the pressures measured during the test from the chamber <br />and axial pressures applied. Results of the triaxial compression tests are shown on Figures #25 and <br />#?b. <br />Uniaxial Compressive Streneth: Unconfined compressive svength testing was conducted on samples of <br />the relatively undisturbed soil and bedrock samples. Each sample was prepared by cutting the end of <br />the specimen parallel to each other and at right angle to the longitudinal axis of [he core. Load was <br />applied continuously and without shock [o produce a constant rate of deformation during the test was <br />recorded. Results of [he uniaxial compressive sveng[h testing are summarized in Table i. <br />Permeability Testin¢ Undisturbed samples obtained during the field investigation far the <br />sedimentation pond were tested in the laboratory to determine the in-situ permeability (k) of the soils. <br />More specifically, the falling head permeability tests were used to the permeability of the soils. Results <br />of these tests are included in the Sedimentation Poud Considerations section of this report. <br />• <br />4 <br />