Fracture Parameters for Cracked Cylincal Shells

Abstract

In this paper, 2D boundary element stress analysis is carried out to obtain the <em>T</em>-stress for multiple internal edge cracks in thick-walled cylinders for a wide range of cylinder radius ratios and relative crack depth. The <em>T</em>-stress, together with the stress intensity factor <em>K</em>, provides amore reliable two-parameter prediction of fracture in linear elastic fracture mechanics. <em>T</em>-stress weight functions are then derived from the <em>T</em>-stress solutions for two reference load conditions corresponding to the cases when the cracked cylinder is subject to a uniform and to a linear applied stress variation on the crack faces. The derived weight functions are then verified for several non-linear load conditions. Using the BEM results as reference <em>T</em>-stress solutions; the <em>T</em>-stress weight functions for thick-walled cylinder have also been derived. Excellent agreements between the BEM results and weight function predictions are obtained. The weight functions derived are suitable for obtaining <em>T</em>-stress solutions for the corresponding cracked thick-walled cylinder under any complex stress fields. Results of the study show that the two dimensional BEM analysis, together with weight function method, can be used to provide a quick and accurate estimate of <em>T</em>-stress for 2-D crack problems.