Random trials used in determining global minimum factors of safety of slopes

The minimum factor of safety of a slope can be found by using various methods of optimization or by random search. This paper presents a combined approach that uses the random search to find an estimate of the global minimum which is employed by the methods of optimization as a starting point. Guidelines have been given to select an appropriate number of random trials. Two simplified methods for calculating the factors of safety are suggested to minimize the computing time of the random searches. The approach has proved to be more efficient than either a purely stochastic or a deterministic one.