Stability analysis of sloping grounds in unsaturated soils using the method of stress characteristics

An extension of slip line theory to unsaturated soils is presented in this research and applied to the problem of stability of slopes in unsaturated soils. The matric suction was then introduced and applied to governing equations based on the well-known Bishop effective stress concept. In this regard, the van Genuchten model was utilized to estimate the effective stress parameter required for measuring effective stress. The in uence of the soil matric suction on the stability of slopes was investigated for a variety of soils under steady-state evaporation and inltration, i.e., distribution of the matric suction was assumed to remain constant with time. In addition, a measure of stability in terms of some stability factors was introduced.