Delamination of Unidirectional Glass Fibre-Epoxy with Cut Plies Loaded in Four Point Bending

Abstract

Constant thickness unidirectional specimens with plies cut across the complete width have been tested in four point bending. With the cut plies on both the tension and compression side, specimens failed by delamination initiating above and below the ends of the cut plies, and propagating along the interfaces between continuous and discontinuous plies. Finite element analysis has been carried out to determine the stress distributions and strain energy release rates, and an analytical expression for the strain energy release rate has also been derived. Predictions of the delamination stresses correlate well with measured values.