9530464 The objectives of this research program are to investigate and clarify fundamental questions in relation to the geostatic stress condition in undisturbed ground, as well as in clays and granular soils subjected to sampling, in situ testing, earthquake shaking, or construction operations, including ground modification. Effective horizontal pressure has a significant effect on resistance to settlement and liquefaction of granular soils. as well as on ground response to in situ tests before and after ground modification. The specific questions formulated for investigation include the permanent effect of pre-shearing on the horizontal pressure in the laterally constrained level ground condition, and settlement of clean granular soils subjected to cyclic pre-shearing. The research method relies on exacting experimental techniques and long-term laboratory and field observations, as well as mathematical modeling and numerical analysis. High quality undisturbed samples of natural clays, as well as reconstituted specimens of natural sand deposits, are used in the laboratory investigations. ***
