Engineering Fracture Mechanics

On the basis of the Dugdale model, approximate weight-function procedures for crack analysis, and a crack-opening shape criterion for continuing crack growth, theoretical curves for tearing resistance were derived for thin flat sheets of finite size. The substantial effects of finite specimen size and initial tearing resistance were thereby revealed. This work was extended to circumferential cracks in cylindrical shells subjected to bending for which crack growth resistance curves. The singular fields around the tips of growing cracks in linear-hardening materials were calculated for a variety of conditions. The actual magnitude of the singularity strength was also calculated, for steady crack growth, as a function of the applied stress- intensity factor and strain-hardening of the material.