Computer simulation of low-velocity impact process of the composite laminate with defect

Computer simulation of the low-velocity impact process of the composite laminate with prefabricated defect was performed to demonstrate the impact process and damage progress in detail. A finite element program written in FORTRAN was developed to analyze the transient dynamic response of composite plates. The Hertzian contact law was modified in order to accommodate the serious damage in the plate. The Wilson-scheme was adopted to perform time integration for the motion equations of the impactor and composite plate system. The Lagrange multiplier method was used to deal with dynamic contact problems. The results of computer simulation including the force history and delamination areas were found to correlate well with the experiments. The experiment and calculation results show that the delamination defects in the laminates have the effect that prevents the propagation of delamination.