An Analysis for Crack Instability in Elastically Confined Yielding Regime

Abstract

An analysis for crack instability is presented which utilizes a J -integral-based tearing modulus approach. In particular, a plane stress center-cracked panel which experiences elastically confined yielding is analyzed for a displacement controlled loading. The analysis assumes a compliant loading system, a special case of which leads to a load control mode of loading. The effects of the crack tip plasticity are taken into account by using the strip-yield model of Dugdale-Barenblatt. A method of predicting the amount of crack growth at the onset of instability is presented. Numerical results suggest that under conditions of small-scale yielding, crack instability can be achieved in materials having very low tearing modulus values.