Shear band evolution and post-failure simulation by the extended material point method (XMPM) with localization detection and frictional self-contact

An enhanced XMPM formulation is proposed to simulate the evolution of shear bands and post-failure behaviors with large deformations. In the current study, a localization search algorithm based on the theory of bifurcation is integrated into the XMPM to predict the initiation and propagation of discontinuity. In addition, a formulation of self-contact is proposed to deal with the dynamic frictional contact mechanism between the generated shear planes. In order to ensure the smoothness of the discontinuity surface during localization propagation, a hybrid implicit-explicit description of discontinuity is assumed by employing the level-set method and a point cloud approach. Several numerical examples are investigated to assess the accuracy and demonstrate the capability of the proposed XMPM approach in simulating the shear band evolution of different engineering problems in both 2D and 3D. The proposed formulation also exhibits minor sensitivity with respect to mesh refinements in predicting the shear-band path. To show the optimum performance compared to the regular MPM approach, a simulation of large-deformation heterogeneous slope failure is presented as one of the applications of the proposed method towards simulating real-scale engineering problems.(c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).