Abstract: With the economic development, the ecological, geological and environmental problems are becoming an ever increasing concern. The stability of the mining slopes is a very important engineering problem. In this paper, the reliability evaluations are performed on the mine material slopes using conventional force limit equilibrium and point estimate methods in a mine in, Hubei Province. Both the factors of safety and the reliability indices are obtained throughout these analyses. The finite difference numerical analysis models are also established using software FLAC3D. The displacement and the rate of the deformation of the slope are evaluated and the factor of safety is also obtained through the numerical analysis. The factors of safety are also analyzed by different limit equilibrium methods, such as, Swedish, Biship and Janbu methods. The results indicate that the engineering geology environment factors, such as, cohesion, internal friction angle and the unit weight, have large impact on the stability of the slope. The numerical analysis results by FLAC3D are consistent with the other simplified analytical results. Under the special environment of in the mining area, the point estimate method can effectively avoid the errors originated from the uncertainties. The simple analytical approach and reasonable results have a significant advantage over other methods. It is also concluded that, for a complicated slope problem with higher requirement, multiple analyses are desired in order to result in the reliable conclusions.

Key words: Force Limit Equilibrium Method, Point Estimate Method, Slope Stability, Reliability Indeices, Safety Factors