Progressive damage modelling of hybrid RTM-made composite Î -joint under four-point flexure using mixed failure criteria

This paper deals with four-point flexure tests on hybrid Π-joints, made out of multi-layer carbon fiber/epoxy resin reinforced composites, processed using the RTM (resin transfer moulding) technique. Static bending properties and failure mechanism were determined by experimental observations. Failure of the Π-joints in four-point flexure tests was through interlaminar debonding in triangular zone followed by debonding propagation along the interface between the triangular zone and the adjacent boundary angle until complete breakage of the top skin. A progressive damage model (PDM) based on mixed failure criteria was developed to predict failure loads. Good correlation was achieved between experimental and numerical results.