Methodology for handing singular points on the Mohr-Coulomb yield surface in elasto-plastic computational procedures

In order to dealing with the singular points on the Mohr-Coulomb yield surface in elasto-plastic computational procedures,two constitutive integration algorithms were developed by analyzing the corner smoothness and vector return methods,used to guide the stress of Gauss points to return to the yield surface.Then the two algorithms are applied to a slope elastoplastic computational procedure successfully.Computational results show that the corner smoothness method can be simply operated,but it has low efficiency and converges slowly;that the vector return method has clear routes to the stress retunes,and is more efficient and converge quickly than the corner smoothness method.