FINITE-ELEMENT COMPUTATION OF THE STRAIN-ENERGY RELEASE RATE FOR KINKING OF A CRACK

The approximate energy release rate for a crack which extends, or "kinks", away from its original direction has been computed by finite element analysis using three different methods: stiffness derivative procedure, J integral method and crack closure integral procedure. A case study is presented to compare the computational accuracies. It suggests that a satisfactory approximation can be obtained provided that the ratio of kink length to original crack length, l(0)/a≤0.04, despite the interaction of the crack tip and knee stress singularities. © 1990 Kluwer Academic Publishers.