An elastic-interface model for buckling-driven delamination growth in four-point bending tests

The paper presents a mechanical model of a four-point bending test on a delaminated specimen, considered as an assemblage of laminated beams partly connected by an elastic interface. A differential problem with suitable boundary conditions is formulated to describe the model. Then, an analytical solution is determined for both the pre- and post-critical stages. A mixed-mode fracture criterion is applied to predict the onset of delamination growth. The model is il-lustrated through comparison with some experimental results taken from the literature.