Prediction of impact induced penetration and delamination in thick composite laminates

A static punch curve was used as the 'structural constitutive model' to capture the highly nonlinear behavior of the laminate in the penetration process of thick laminates. A penetration model based on a ring element was first used to simulate the static punch curve. The model was then used to predict the dynamic penetration process of large panels using the information obtained from the static punch curve of a smaller specimen. The model was shown to predict the penetration process for short and long projectiles. The area of the target that becomes delaminated during impact was shown to increase when the impact velocity was increased until the ballistic limit, beyond which the delamination area decreases with an increase in impact velocity. This phenomenon and the area that is delaminated for different size targets at different impact velocities were accurately predicted by the ring element model in conjunction with a critical shear strain criterion. Copyright (C) 1996 Elsevier Science Ltd.