A simple model for the prediction of the fatigue delamination growth of impacted composite panels

The fatigue behaviour of composite panels that have been subjected to low‐velocity impact was studied. Impacted specimens were tested under compression–compression fatigue. A delamination propagation model based on the derivation of the strain energy release rate was used. The stress distribution around the initially induced delamination was derived analytically. The shape of the delamination was experimentally monitored by c‐scan imaging and is assumed to be an ellipse. The orientation and aspect ratio of the ellipse were used to calculate the corresponding strain energy‐release rates, which were subsequently used to predict the direction of delamination propagation.