Perforation studies on flat bars for XFEM-based failure analysis

• Load bearing capacity reduction due to circular perforations of different diameters.
• Comparison of load–deformation experiments for non- and perforated flat bars.
• DIC digital imaging to monitor displacement and strain fields near perforations.
• XFEM and localization analysis for crack initiation and propagation in alloys.

This paper revisits the stress concentration problem in the proximity of circular perforations of different diameters and presents results of an experimental program on flat bars made of high strength steel, mild steel, cast iron and aluminum alloys. A digital image correlation (DIC) system is used to monitor the experiments and provide displacement and strain fields on the surface of the specimens at different stages of axial loading. The extended finite element method (XFEM) is introduced and applied to the inelastic deformation regime by coupling localization analysis and XFEM to discretely follow crack propagation into the ductile response regime.