PREDICTING THE SHEAR STRENGTH FUNCTION FOR UNSATURATED SOILS USING THE SOIL-WATER CHARACTERISTIC CURVE

The shear strength of unsaturated soils can be computed using the soil-water characteristic curve and the saturated shear strength parameters of the soil. Closed-form solutions for the prediction of unsaturated shear strength are developed in this paper using simple soil-water characteristic curve equations available in the literature. These closed-form solutions are not suitable for all types of soils and large ranges of suction. A general form for the shear strength equation of unsaturated soils using a rigorous soil-water characteristic curve equation is also developed in this paper. The proposed models make use of the soil-water characteristic curve and the saturated shear strength parameters to predict the variation of shear strength with respect to suction. (A) For the covering abstract see IRRD 881647.