Compressive brittle fracture in V-notches with end holes

The aim of this research was to present a brittle fracture model for predicting the compressive failure load of engineering components weakened by V-notches with end holes (VO-notches). For this purpose, two well-known brittle fracture models in tension, namely the point stress (PS) and the mean stress (MS) were applied to the compressive stress field around the VO-notches and for each model a closed-form expression was obtained for the compressive mode I notch fracture toughness. In order to evaluate the validity of PS and MS criteria, the theoretical values of compressive notch fracture toughness were compared with the experimental results reported recently in literature dealing with fracture in fine-grained isostatic graphite plates containing V-notches with end holes subjected to pure compression. The results showed that while the MS model with a total discrepancy of 5% was an appropriate failure criterion, the PS model with about 86% accuracy could not predict the experimental results satisfactorily.