A Virtual Crack Closure-Integral Method for Generalized Finite Element with Drilling and Strain Degrees of Freedoms

Abstract

A virtual crack closure-integral method (VCCM) for the generalized finite element with drilling and strain degrees of freedoms (DOFs) is presented in this paper. Free mesh method (FMM) is one of useful methods for fracture mechanics analysis. However, in FMM, quadratic elements with mid-side nodes cannot be employed due to restrictions arising from its local mesh generation rule around each node. Generalized elements with drilling and strain DOFs which have no mid-side nodes may improve the accuracy in fracture mechanics analysis over the conventional constant strain elements. Present authors have proposed a VCCM for two-dimensional generalized elements with drilling DOFs, in their previous papers. In this paper, in order to improve the accuracy in fracture mechanics analysis further, we present a VCCM for generalized finite element with drilling and strain DOFs. Finally, some numerical examples are presented and it is demonstrated that the generalized element with drilling and strain DOFs has superior accuracy over that with drilling DOFs only.