A Smoothed Finite Element Method (S-FEM) for Large-Deformation Elastoplastic Analysis

An edge-based smoothed finite element method (ES-FEM) using 3-node triangular element was recently proposed to improve the accuracy and convergence rate of the standard finite element method (FEM) for 2D elastic solid mechanics problems. In this research, ES-FEM is extended to large-deformation plasticity analysis, and a selective edge-based/node-based smoothed finite element (selective ES/NS-FEM) method using 3-node triangular elements is adopted to address volumetric locking problem. Validity of ES-FEM for large-deformation plasticity problem is proved by benchmarks, and numerical examples demonstrate that, the proposed ES-FEM and selective ES/NS-FEM method possess (1) superior accuracy and convergence properties for strain energy solutions comparing to the standard FEM using 3-node triangular element (FEM-T3), (2) better computational efficiency than FEM-T3 and similar computational efficiency as FEM using 4-node quadrilateral element and 6-node quadratic triangular element, (3) a selective ES/NS-FEM method can successfully simulate problems with severe element distortion, and address volumetric locking problem in large-deformation plasticity analysis.