Abstract:Three-dimensional finite element method is used to simulate the dislocation of a fault beneath the core wall of a rockfill dam;and the influence of the dislocation upon the core rockfill dam,especially upon the seepage prevention system(including clay core wall and concrete cut-off wall) is investigated. It is supposed that the maximum dislocation is 50 cm,and the dislocation direction is vertical or horizontal. Furthermore,the stress-deformation behavior of dam with fault dislocation is compared with that of the dam without fault dislocation. The simulated results indicate that the overburden consisted of granular soils which is about 70 m in thickness plays an important role is reducing the dislocation to transfer to the dam including the core. In the case that fault dislocation is 50 cm,the stress level of the clay core increases with a magnitude of 0.4–0.6 MPa,and there is no abrupt deformation in the core. If the dislocation is limited with 50 cm,it will not induce the failure of the dam itself,but will result in the local damage of the concrete cut-off wall nearby the fault. Further study on seepage is necessary due to the damage of the concrete cut-off wall.