Analysis of 3D cracked components repaired by adhesively bonded patches using FEM-BIEM coupling

Abstract

This research proposes an accurate computational procedure for the three-dimensional analysis of cracked components after being repaired by patches with the adhesive bonding. The technique was implemented based on the coupling between a finite element method (FEM) and a weakly singular, boundary integral equation method (BIEM). The FEM was utilized to tackle both the patches and adhesive layers, whereas the BIEM was employed to efficiently handle the elastic cracked medium. To enhance the approximation, an asymptotic structure of the near-tip field is properly integrated in the discretization of the jump in the crack-face displacement in the vicinity of the crack boundary. This, in addition, offered a direct means to post-process for the stress intensity factors (SIFs) in terms of the solved data along the crack front. Extensive results are then reported to demonstrate the accuracy and convergence of the implemented BIEM-FEM coupling and the effect of the relative stiffness of the patches and adhesive layers on the reduction of the SIFs along the crack front.