FAILURE PREDICTION TECHNIQUE FOR COMPRESSION LOADED CARBON FIBER-EPOXY LAMINATE WITH OPEN HOLES

The inplane compressive fracture behaviour of a carbon fibre-epoxy laminate containing a single hole is examined. Failure is due to 0-degrees 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.