Combined resonant-column/torsional-shear tests were performed on four specimens of marine clay collected at varying depths over a range of confining pressures commensurate with the specimen depths. Using the small-strain measurements from these tests, the influences of stress state and void ratio on the small-strain shear stiffness, shear-wave velocity, and material damping ratio were studied. As the confining pressure increases and the specimen consolidates, both the shear stiffness and velocity increase. The rate of this increase follows typical trends of consolidation curves: less sensitive during recompression and unloading, and more sensitive during virgin compression. The laboratory-measured V_s showed good agreement with the field values with little evidence of sample disturbance. The influence of stress on G_(max) and V_s was also found to be in good agreement with the laboratory. The relationship between the stress state, void ratio, and material damping is more complicated and does not show as consistent a behavior.
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