Abstract: To investigate the influence of seepage and flow-rock mass coupling effect on slope stability, the equivalent continuum model was firstly introduced based on geological conditions, then the infinite element method was used to solve the model.Finally, the software SEEP/W was adopted to simulate the underground seepage under the conditions of normal water level, rainfall infiltration and drainage.The results show that the equivalent continuum model is reliability, and the two dimensional seepage is inhomogeneous with axial hydraulic gradient greater than radial gradient.Three modes indicate that hydraulic gradient is evident within the slope surface, intersections of different stratums and mixed rock mass Ⅰ.In addition, the rainfall infiltration results in tensile stress increase and fracture enlargement, shearing and slippage is the main inducement mechanism for slope instability, whereas drainage is efficient to improve the slope safety.

Key words: Equivalent continuum model, Numerical simulation, Shearing and slippage, Drainage