Reliability Analysis of Load and Resistance Factor Design of Slopes

Abstract

AbstractA logical framework is developed for the LRFD of slopes based on reliability analysis. The LRFD of slopes with resistance factors developed in this manner ensures that a target probability of slope failure is not exceeded. Three different target probabilities of failure (0.0001, 0.001, and 0.01) are considered in this paper. The ultimate limit state for slope stability (formation of a slip surface and considerable movement along this slip surface) is defined using the Bishop simplified method with a factor of safety equal to 1. Gaussian random field theory is used to generate random realizations of the slope with values of strength and unit weight at any given point of the slope that differ from their mean by a random amount. A slope stability analysis is then performed for each slope realization to find the most critical slip surface and the corresponding driving and resisting moments. The probability of slope failure is calculated by counting the number of slope realizations for which the factor...