A hybrid Monte Carlo-Simulated Annealing approach for reliability analysis of slope stability considering the uncertainty in water table level

Abstract

Slope stability analysis is one of the most challenging problems in geotechnical engineering. Due to the uncertainty involved in the problem, probabilistic methods are recently utilized to estimate the probability of slope failure. In this study, the slope stability is presented as an optimization problem and the Simulated Annealing (SA) method is used to identify the slip surface with the minimum safety factor. The SA algorithm is then integrated with the Monte Carlo sampling method to calculate the probability of slope failure. Next, the groundwater level is added to the problem formulation as a random variable to model the uncertainty for cases where the groundwater table is not accurately determined. The results of the analysis showed that for slopes with low safety factors, the uncertainty of the groundwater table worsens the condition and increases the failure probability. Moreover, the parametric study showed that the insufficient understanding of groundwater level distribution and the assumption of uniform distribution further increases the failure probability. The results of this study are presented in the form of a probability curve against the groundwater table. This presentation has practical applications in real projects.