Effect of T-stress on the fracture of a four point bend specimen

Recent studies have shown that considering the effect of higher order terms and constant term in Williams Series in the fracture mechanics problems leads to better results. These terms play a significant role in determining the stress and strain fields and the energy around the crack tip which in turn can affect the fracture of the specimen predicted by different fracture criteria. In this paper, the effect of T-stress on the crack growth initiation angle in brittle materials and in elastic state is studied. For this purpose, a four point anti-symmetrical bend specimen, capable of creating mixed mode, is considered. The problem is analyzed with the aid of finite element method (FEM). The results are validated comparing them with the existing results in the literature. Finally, the effect of specimen geometry on the T-stress value and effect of T-stress on different fracture criteria will be assessed. (C) 2008 Elsevier Ltd. All rights reserved.