A revised failure criterion for brittle elastic materials under mixed-mode loading in 2-D

Abstract

We revise the failure criterion by Yosibash, Priel and Leguillon for V-notched 2-D domains made of brittle elastic materials (Yosibash et al., 2006) under mixed-mode loading. It is based on a finite fracture mechanics (FFM) concept that requires the determination of a finite virtual crack that simultaneously satisfies the normal stress criterion and the energy release rate (ERR) criterion. The FFM ERR criterion is extended to include mode II toughness (GIIc) and reduces to the classical fracture mechanics failure criterion under constrained mode II at the limit when the V-notch solid angle approaches 2π.The revised criterion predictions of failure load and failure initiation angle are compared to experimental observations on PMMA V-notched specimens under mixed mode loading. The predictions compared to the original criterion are slightly improved, especially as the mode mixity ratio increases.