Crack-Tip Stress Singularity Field of a Mixed-Mode Three-Dimensional Crack : 1st Report, Comparison of Mixed-Mode Stress Intensity Factors and J-Integrals Obtained through Displacement Method, J-Integral Formulation, and Modified Crack-Closure Integral

Abstract

Two- and three-dimensional finite-element analyses have been conducted on a compact normal and shear specimen under mixed-mode loading. This paper presents a comparison among stress-intensity factors and J-integrals for mixed-mode problems obtained through three different approaches : the displacement method, J-integral formulation and modified crack-closure integral. The accuracy of these methods is discussed. The mixed-mode J-integral and modified crack-closure integral estimate the J-integral components for an arbitrarily mixed-mode three-dimensional crack well. The accuracy of the displacement method is discussed with respect to plane strain and stress conditions.