Abstract: Finite element software Phase2 together with two-dimensional seepage numerical calculation method was used to build a numerical model in consideration of the influence of seepage field on slope stability. The displacement field,stress field and pore water pressure field were analyzed. The result indicated that rainfall infiltration resulted in the increase of pore water pressure in the soil,and decreases of matrix suction and shear strength. As rainfall duration increased,slope’s safety factor reduced. As slope displacement reached the maximum,matrix suction of the slope surface began to increase due to the further infiltration of rain. And as the water draining through the groundwater saturation zone,the water content and bulk density of soil decreased,which delayed the effect on slope stability.

Key words: road engineering, rainfall infiltration, numerical simulation, stability analysis, seepage field