Drained cylindrical cavity expansion in modified Cam-clay soil under biaxial in-situ stresses

A drained solution is derived for cylindrical cavity expansion in modified Cam-clay soils under biaxial in-situ stresses. The problem is formulated by solving a system of first-order differential equations using an auxiliary variable, which provides semi-analytical expressions for stresses and specific volume. The solution validity is examined through comparisons with the existing solution and the finite element simulation. The results show that the elastic-plastic boundary of cylindrical cavity expanding under biaxial in-situ stresses is an ellipse, due to the existence of shear stress. Besides, the stress distribution and the stress path change significantly with the variation of radial direction.