Coupling analysis of seepage and stress of the unsaturated soil under the rainfall condition

The mechanical parameters of rock mass in reservoir bank would be affected by the changes of water level and the rainfall condition, and the slope stability would be change with that. the coupling of seepage and stress of unsaturated soil, considering the condition of rainfall, is analyzed in this paper. The water head distribution and critical line of pore water pressure got by the seepage analysis are useful for practical engineering. The sensitivity analysis is taken to study the effect of mechanical parameters of soil on slope stability. The results show that the parameter of cohesion is most sensitive to the safety factor of slope, the friction angle is in second and the unsaturated shear strength angle is least sensitive.