Robust Estimation of Inelastic Fracture Energy Release Rate (J ): A Design Approach

Abstract

There are insufficient details during preliminary stages of a pressure component design to warrant a comprehensive inelastic determination of the fracture energy release rate, J. A simplified formulation for estimating J, described in this paper, relies on a knowledge of the linear elastic stress-intensity parameter and the plastic collapse load. Subsequently, an expression for J is provided in terms of the r-node strain, which serves as an upper bound in the elastic-plastic regions for components subjected to mechanical loads. Estimates of J for several standard configurations have been obtained by inelastic FEA, and the comparisons with the corresponding robust estimates are reasonable.