Design and application of an automated non-circular slip surface search within a combined hydrology and stability model (CHASM)

With geotechnical engineering the form of slope stability analysis most com monly used is the Bishop circular method. By assuming a circular shape, how ever, the method results in an overestimation of the factor of safety. This is because failure surfaces are often non-circular, given the heterogeneit y of both hydrological and geotechnical slope characteristics. This problem is addressed by adapting an automated search algorithm for non-circular fa ilure surfaces. The numerical method is based on a random search technique for the global minima of a constrained non-linear optimization problem. Thi s is incorporated into a combined hydrology and stability model (CHASM) tha t allows the simulation of changes in pore-water pressures in response to i ndividual rainfall events, and considers their role in maintaining slope st ability. Initial results suggest that the implementation of the automated s lip search algorithm leads to an improvement in the evaluation of slope sta bility in comparison to other less rigorous approaches. Copyright (C) 2000 John Wiley & Sons, Ltd.