Investigations in a Cracked Plate Under Bending

Abstract

This work focuses on the study of bending effects on the closure of crack faces and the resulting effects on the stress intensity factors. A plate with a pre-existing through-the-thickness crack is considered under the action of a remote bending moment. This bending induces contact of the crack faces, which introduces additional load along the crack extension and strongly influences the stress intensity factor, the stress and the displacement fields at the crack tip. To the knowledge of the authors, there are few if any experimental studies of fracture in plates subjected to bending, and in particular, cyclic loading of propagating cracks in such plates. Steel sheets were used as specimens and the loading was cyclic pure bending. Three-dimensional finite element analyses using FRANC3D and ABAQUS are compared with the experimental results. Contact was modeled in the numerical analyses. The influence of the contact on the crack tip is investigated for three thicknesses and three geometries. It was found that the edge contact at the crack tip varies with different thicknesses. However, for the same thickness but varied geometry, the edge contact is the same. The numerical results agree with the experimental results.