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of the shale fill when cor,:pacted to 90/ of the standard Proctor <br /> density. Tests were performed at confining pressures of 20, 40, <br /> and 60 psi. The test indicated a friction angle = 290, and a <br /> cohesion c = 1295 psf. Triaxial test results are shown on plate <br /> 3 . <br /> The underlying native soil, as ob- <br /> served in the test pits, is essentially a granular material, with <br /> grams ranging from silt-size to boulder-size. It was felt that <br /> the direct shear test would be most appropriate for this material. <br /> The direct shear test indicated a peak friction angle of 440 with <br /> a cohesion of 400 psf, and a residual friction angle of 330 with <br /> a cohesion of 240 psf. The residual friction angle and cohesion <br /> were selected for purposes of slope stability analysis , being the <br /> most conservative. <br /> A rock correction was performed on <br /> the direct- shear sam- ple prior to testing, which involved rejecting <br /> all material larger_ then 2 ircl,es diameter; and screening our r-.at- <br /> erial betwean 2-inch and 3/4-inch diameter and replaci.-ig this with <br /> the same weight of -material less than 311/4-inch diameter, but larger <br /> than a #4 U. S. Seive'. This .resulted in a saf;:ple with sufficient <br /> small particle size to per:r.it testing, but with an equivalent <br /> weight of material in the gravel-size range. It should be noted <br /> however, that -chile the standard rock correction requires rejection <br /> of plus 2-inch material, greater than 50"/0 of the native soil on <br /> which the fill is to be placed consists of particles greater than <br /> 2 inches diameter. Therefore, it is felt that the direct shear <br /> represents a conservative approach in this instance. <br /> -3- <br />