Application of finite element analysis techniques for predicting crack propagation in lugs

Abstract The plane elastic problem corresponding to a through radial crack emanating from the internal boundary of a symmetrical lug is considered. A pin bearing pressure distribution was developed by utilizing photoelastic test data and differs considerably from the usually assumed uniform or cosine pressure distributions. The stress intensity factors at the crack tip were obtained by using recently derived quadratic isoparametric finite elements which embody the inverse square root singularity. Fatique crack growth tests of 17 aluminium, titanium and steel lugs were utilized to verify stress intensity factor solutions.