Failure prediction technique for compression loaded carbon fibre-epoxy laminate with open holes

The inplane compressive fracture behaviour of a carbon fiber-epoxy laminate containing a single hole is examined. Failure is due to 0° fibre microbuckling surrounded by delamination. The microbuckled zone initiates at the hole boundary. It extends stably under increasing load before becoming unstable at a critical microbuckle length of 2-3 mm. The damage propagation and failure of the orthotropic laminate is analysed by a cohesive zone model, in which damage around the open hole is represented by a line crack loaded on its faces. Good agreement between experimental and predicted notched strength is observed for the chosen material and lay-up.