Formula omitted] applied to stress-strain concentrations

Abstract

J. R. Rice's 1968 paper introduced the J- integral for analysis of stress concentrations at cracks and notches. Using the J- integral , we develop a new approach for estimating stress-strain concentrations at notches. We consider a three-point-bend specimen containing a notch with a semi-circular root. We show that direct finite element analysis results for stress-strain concentrations at notch roots depend strongly on mesh refinement, while both the J- integral and the notch root stress and strain calculated from the J- integral are much less sensitive to mesh refinement. We also show that, since the J- integral is nearly insensitive to small-scale yielding, the computational burden of analyzing notches can be reduced significantly by using linear elastic analysis and by avoiding the need for mesh refinement at notch roots. An example of application of this method to life prediction is given.