Assessing the Stability of Slopes Using Vector-Sum-Based Numerical Manifold Method and Pattern Search Algorithm

The Numerical Manifold Method (NMM) has been considered as an effective analysis method for geotechnical problems. A vector-sum-based numerical manifold method (VSNMM) combined with a pattern search algorithm (PSA), termed VSNMM-PSA, is further proposed to assess the stability of slopes. In this numerical method, PSA is applied for the determination of failure surface location. With the stress field of the slope obtained from a NMM-based elastoplastic calculation, the vector sum method (VSM) is used to predict trial safety factors for a series of trial failure surfaces (TFSs) during the failure-surface determination process. Stability analyses about three standard slopes are investigated with the proposed VSNMM-PSA model. Numerical results indicate that slopes' safety factors and failure surfaces can be accurately determined through the proposed VSNMM-PSA method. The proposed VSNMM-PSA method provides an effective tool to evaluate slopes' stability, and may improve their designs.