Fracture behavior of aramid/epoxy composite with a circular hole subjected to compressive load

In this paper, a method for predicting compressive strength of notched AFRP (Aramid Fiber Reinforced Plastics) is proposed. The compression tests are performed with an end-tab compression method based on the NASA/ Boeing standards. In the experimental procedure, both unidirectional and woven cloth AFRP specimens show the hole radius dependency of the compressive strength. It is also found that the failure modes can be classified by two failure criteria. Therefore, each failure criterion is applied to predict the compressive strength for each failure mode. A fracture simulation is carried out using FEM to predict the compressive strength of the notched AFRP. Fiber micro-buckling is represented by variation of the stiffness of the element at the elastic-plastic stage. The Tsai-Hill law is applied as a yielding criterion, and the maximum compressive strain theory is applied for fracture criterion. The load-displacement curve and compressive strength of the unidirectional AFRP are well simulated. On the other hand, it is found that the woven cloth AFRP is simulated only in the initial failure process. It can be concluded that the proposed fiber micro-buckling model is appropriate to explain the complicated buckling mechanism of laminated composites.