Drag Force Effect of Surface Runoff on Stability of Shallow Soil Slope

Abstract

The softening and degradation effects of water on soil mass, increase of pore water pressure, and reduction of matric suction are usually considered for analyzing the contributions of rainfall to the failure of shallow soil slope. However, the effect of drag force at the fluid-solid interface due to slope surface runoff also deserves to be taken into account. To quantitatively investigate this effect, a modified approach based on the limit equilibrium method is proposed by establishing a nonlinear coupled mathematical model. The calculation results show that the effect of drag force at the fluid-solid interface should not be neglected especially when the runoff on shallow soil slopes is relatively deep.