Abstract: The shape feature of slope failure surface isn’t changed obviously when the rock mass strength parameters are varied,cohose characteristic is used to determine potential failure surface of slope in the process of numerical simulation. This way is simply and easily applied. It is applied in the study of a man-made high slope stability in Guangzhou Science City. In the course of three dimension numerical simulation, the rock mass strength parameters are reduced to get the distribution maps of shear strain increment. The potential failure surfaces of different profiles are obtained from these maps. There is different between the potental failure surfaces and medium erosion surface that is usually thought potential failure surface. The stability of slope is computed by limit balance method. It is known that the safety factors of different profiles are greater than 1.2, so the slope is thought as stability, but need to be reinforced by some ways. The results obtained by limit equilibrium method and numerical simulation are consistent. So the potential failure surface is searched properly and these results are reliable. It should be considered as one of these methods of searching potential failure surface of slope.

Key words: numerical simulation, the safety factor, potential failure surface, limit equilibrium method