Simulation study on interfacial debonding caused by spatially distributed damages in unidirectional fibre composites using 2D model

Influences of spatially distributed damage (broken fibre, matrix and interface) on the progress of interfacial debonding were studied by using a two-dimensional model. It was shown that the debonding progresses intermittently in weakly bonded composite, resulting in serrated stress-strain curves; the overall debonding progresses more rapidly with increasing number of damages due to the enhanced mechanical interactions among damages; and the progress of debonding varies, depending on the geometrical position of the damages, residual stresses and frictional shear stresses at debonded interface. The practically observed feature that the strongly and weakly bonded composites tend to show noncumulative and cumulative fracture modes, respectively, could be realised in the computer by the proposed simulation method.