A double-plate finite-element model for the impact-induced delamination problem

Abstract A double-plate model is proposed to simulate a composite laminate with impact-induced delamination. Mindlin plate finite elements with large deflection have been employed to calculate stress and strain fields. On the basis of the modified crack closure method, a general expression for the strain energy release rate at the delamination front is derived. The proposed model was first evaluated by using an isotropic double cantilever beam. It is shown that this model is simple and computationally efficient. Subsequently, the present model was employed to predict impact-induced delamination in composite laminates and was compared with experimental results. The effect of shear cracks in the lamina adjacent to the delamination is discussed. The similarities between delaminations produced by different impact loads is identified and investigated by the use of the double-plate model.