Direct prediction of fracture for two-dimensional plane stress structures

Abstract

This paper presents a procedure for the direct prediction of fracture in two-dimensional structures subjected to plane stress conditions as the result of monotonically increasing loads. The procedure is based on standard finite element methods coupled with incrementally linear element material properties and a zero modulus-unload reload scheme to advance the fracture surface. Comparisons of numerical and experimental data show that the procedure can accurately predict load-deflection curves, load and deflection at fracture, and fracture initiation sites for two-dimensional structures with either mild or severe stress concentrations located anywhere in the structure. Plasticity zones and stable or unstable fracture can also be predicted. The procedure is shown to highly dependent on the mesh density along anticipated crack paths for severe stress concentrations.