Crack propagation modelling in XFEM with double enriched nodes

摘要

In the paper, the extended finite element method (XFEM) is used to solve two-dimensional crack propagation problems within the linear elastic fracture mechanics (LEFM) framework. The XFEM is applied to compute the stress field of a cracked structure for the proper estimation of stress intensity factors and, accordingly, the acceptable direction of the crack growth. The crack path is approximated explicitly using an open polyline (straight line segments). Level set functions are used for the definition of enrichment. Three enrichment approaches are considered: standard, geometrical and geometrical with double enriched nodes. The procedures were tested using the examples of a beam with an edge crack and a plate with holes.