Computation of Energy Release Rates for Kinking Cracks based on Virtual Crack Closure Technique

Abstract

A numerical method based on the virtual crack closure technique (VCCT) (Rybicki and Kanni- nen (1977)) and in conjunction with the finite element (FE) method is presented to compute strain energy re- leaserates forcracks that kink. Themethod partitionsthe strain energy release rate and provides an efficient means to compute values of the mode I (GI) and mode II (GII ) energy release rate at the tip of a kinking crack. The solution procedure is shown to be computationally effi- cient and operationally simple, involving only the nodal forces and displacements near the crack tip. Example problems with kinking cracks in a homogeneous mate- rial, and a layered two constituent material are presented to illustratethe current approach. keyword: kinking crack, virtual crack closure tech- nique, energy release rate