Coupling effect on shallow slope stability under infiltration

Abstract

This paper aims to discuss the influence of the coupled deformation of unsaturated soil on the slope stability under rainfall condition. Numerical soil column tests were first performed to display the seepage deformation, and the pore water pressure (PWP) distribution differences of the coupled analysis. Comparative analyses were done for three different analysis cases (i.e., uncoupled analysis, coupled analysis without considering the permeability coefficient (Ks) change, and coupled analysis considering the Ks change) under different infiltration intensity. The analysis results show that the coupled deformation lead to different PWP distribution and factor of safety (FS) profiles in the shallow slope from the uncoupled analysis, and the Ks change caused by seepage deformation plays an important role. There is a great risk for accurately assessing the shallow slope state as to the uncoupled analysis and the coupled analysis without considering the Ks change.