Geomechanics: Suction and Shear Strength

This lecture on Geomechanics covers the concepts of suction and shear strength in unsaturated soils. It explains the air-water-solid phase interaction, the impact of suction on volume changes, and the shear strength envelope. The lecture also delves into the consequences of desiccation, swelling soils, and the behavior of clay barriers. Various tests and models are presented to understand the hydraulic behavior and shear strength of unsaturated soils. The Rankine's theory is extended to unsaturated soils for active and passive states, providing insights into lateral earth pressure profiles. Practical guidelines for retaining structures and the effects of infiltrations on earth pressure are discussed.