A three-dimensional upper-bound approach to slope stability analysis based on RFEM

An upper-bound limit analysis method based on rigid finite elements has been developed recently. Numerical procedures for implementing the three-dimensional upper-bound slope stability analysis using rigid finite elements are presented in the paper. The search for the minimum value of the factor of safety can be set up as a non-linear programming problem. Because of the existence of non-linear equalities, a special sequential quadratic programming (SQP) algorithm, CFSQP, is applied to obtain the optimal solution in the paper. Two test problems are used to examine the validation and capability of the present rigid element upper-bound limit analysis method by comparison with results obtained by other methods. A practical example illustrates the application of the present method in three-dimensional slope stability analysis.