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14 maximum dry density determined by ASTM D 1557. The internal friction angle for this sample exceeded 35 degrees. A design internal friction angle of 30 degrees is suggested for compacted structural fill composed of native silty sands or native silty sands blended with up to 20 percent glass particles. The strength of the lean clay stratigraphic sequence was determined by various laboratory tests. These tests suggest the clay to be stiff to very stiff in consistency. The clay is very stiff and has a slightly higher strength near the top of the sequence. In this crustal zone the undrained shear strength is interpreted to range from 1800 to over 2400 psf. Below the crustal zone, the strength decreases to 1500 to 2000 psf down to about 30-ft depth and then begins to increase slightly with additional depth. The silty sands and poorly graded sands present below about El -20 to -25 are judged based on blow counts and sample densities to be dense to very dense. A 35-degree angle of internal friction is recommended for design. Dynamic Soil Properties The dynamic properties of soils are typically estimated by observing shear wave and compression wave velocities through the soil. These velocities also can be approximated in the laboratory using a resonant column apparatus, or in situ measurements can be made using geophysical cross-hole techniques. Although actual dynamic testing was beyond the scope of this study, a discussion of typical dynamic properties is included. The surface materials encountered down to about 15-ft depth were primarily silty sand fill and glass. The relative density of the silty sand ranged from loose to dense. The materials were generally dry to slightly moist down to about 10 ft and wet below 10 ft. Below the surficial sand and glass fill, stiff to very stiff, lean clays and dense to very dense sands were encountered. The dynamic properties are influenced by the strain amplitude, overburden and confining pressures, void ratio, overconsolidation ratio, degree of satura- tion, and number of cycles of loading. Also, the variation of dynamic properties with depth may be important to the proper dynamic design of a mat or deep founda- tion. Suggested ranges of values for the shear wave velocity, Vs, shear modulus, Gmax, Poisson's ratio, u, elastic modulus, E, and modulus of subgrade reaction based upon the static test results and site conditions are tabulated below: 1144A/CC-14 LiMcClelland