Comparative Analysis of Cyclic Shear Behavior in Sand and Marine Clay Under strain controlled Conditions”

CONCLUSION This research examined the cyclic shear behavior of clay and sand in response to different displacement amplitudes of 0.10 mm, 0.20 mm, 0.40 mm, and 0.50 mm. Through close examination of hysteresis loops and degradation of shear modulus, it was found that: 1.    Differences in Material Response: Sand displayed comparably stable and narrow hysteresis loops over all amplitudes, showing higher elasticity and less energy dissipation. Clay, on the other hand, displayed increasingly wider loops with rising amplitude, illustrating greater damping and plastic deformation. 2.    Shear Modulus Trends: Both materials showed a reduction in shear modulus with increasing amplitude, consistent with strain-dependent stiffness loss. The reduction was more significant for clay, however, which implies higher sensitivity to cyclic loading. 3.    Amplitude Influence: At lower amplitudes (0.10 mm and 0.20 mm), sand was more stiff and less damping than clay. At greater amplitudes (0.40 mm and 0.50 mm), clay's modulus fell drastically, and its hysteresis behavior became progressively more nonlinear. 4.    Impact on Geo technical Design: The opposing cyclic behaviors of sand and clay highlight the significance of material-based factors in seismic and dynamic load conditions. Sand could be more appropriate in circumstances demanding stiffness retention, whereas clay's damping quality might be preferable in energy dissipation applications.

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