Spoke Model for Calculating Reliability Index and Safety Factor of Slopes

Abstract

Considering the disadvantages of the slice method commonly employed in reliability analysis of slopes, a novel method (Spoke model) was proposed for reliability analysis and safety factor calculation of slopes in this work based on geometrical relationship among slices. The safety factor and the coefficients of limit state function of slopes could be achieved with the Gaussian integral method. The minimum safety factor and the minimum reliability index, as well as their corresponding coordinates on the slip surface, can be calculated with the improved JC method and the searching method. A novel and practical method for reliability analysis of slopes has been achieved. With this method the slice process could be avoided, which helps to eliminate some calculation errors caused by oversimplified assumption. Moreover, the explicit expression of safety factor in this method requires no repeated iterative solution, which is employed in traditional slice methods, as well as can be developed into a limit state function required by calculation of the reliability index. It is demonstrated that this method works efficiently and succinctly in evaluation of reliability index and safety factor for soil slopes.