Comments on simulations of fatigue crack propagation by blunting and re-sharpening: The mesh sensitivity

A selection of results of extensive analysis of mesh sensitivity of large-deformation elastoplastic finite element (FE) simulations of a crack under cyclic loading is presented. Notorious mesh sensitivity, which commences at spontaneous shear localization, is evidenced. This is argued to be not a mere numerical artefact, but a consequence of the inherent bifurcating behaviour of the boundary value problem solutions, where different mesh layouts and element technologies could trigger a variety of deformation patterns near the crack tip.