Fracture mechanics analysis of bimaterial interface cracks using an enriched method of fundamental solutions: Theory and MATLAB code

Abstract

Abstract In this paper we study the application of the method of fundamental solutions (MFS) to interface crack analysis in linear elastic bimaterial fracture mechanics. Such problem presents some modelling difficulties because of the oscillatory behavior of the local asymptotic fields in the neighborhood of the interface crack-tip. The present approach is based on the combination of the classical MFS approximation for linear elasticity problems and a set of enrichment functions that take into account the asymptotic behavior of the near-tip displacement and stress fields. The enriched MFS technique automatically incorporates the oscillatory crack-tip behavior and thus can significantly improve the computational accuracy of the displacements and stresses in the vicinity of the crack-tip, even with a relatively coarse MFS model. A multi-domain MFS technique and the displacement extrapolation method (DEM) are used to compute the complex stress intensity factor (SIF) of the cracked bimaterials. Several benchmark numerical examples are presented to illustrate the accuracy and efficiency of the present method. Results calculated by using the boundary element (BEM) method are also given for the purpose of comparison.