Effect of Wetting and Drying on Shear Strength

Climatic changes, such as repeated wetting and drying over geological ages, lead to the degeneration of the parent rock to form soil. Simultaneously these actions can also cause some aggregation of soil particles and the production of bonds, called desiccation bonds, which impart an intrinsic effective stress to the soil. This intrinsic effective stress can influence the shear strength behavior of soils subjected to such climatic actions. When a soil is subjected to repeated wetting and drying in the laboratory, an intrinsic effective stress is imparted to it which results in greater shear strength and in a stiffer stress-strain response. This intrinsic effective stress may be attributed to chemical bonds.