Recovery of 3D stress intensity factors from surface full-field measurements

Abstract

The identification of cracks stress intensity factors (SIFs) in elastic solids from full-field in-plane displacement field measurements is addressed. Because it is known that significant three dimensional effects alter the values of plane stress computed SIFs, and that the overall geometry of the crack front plays also a role, the problem of SIF's identification is tackled here in the full three-dimensional framework. First is derived a data completion method in elasticity enabling the determination of the elastic displacement and stress fields inside the solid, or in the part where the behavior remain elastic, from surface displacements including the case of only in-plane displacement fields measurements over a traction-free surface. Then usual numerical methods for the computation of SIF or energy release rates are used. Numerical applications in three-dimensional elasticityfor true 3D geometry and loading are presented. ©2010 Society for Experimental Mechanics Inc.