Modeling dynamic penetration of thick section composite laminates

摘要

Fiber composites are highly heterogeneous. Thick-section composite laminates may contain hundreds of composite laminae. Under impact loading, extremely complex failure modes would occur. The complexity of the state of damage makes an accurate detailed modeling of damage progression almost impossible. To circumvent this difficulty, a new approach was proposed in which a quasi-static punch test was performed on a composite lamiante to generate the load-deflection curve during penetration. This punch curve can be considered as the "structural constitutive model" that captures the highly nonlinear behavior of the lamiante in the entire pentration process. A special two-noded ring element based on the mindlin thick plate theory was formulated to model damage processes during staitc and dynamic penetration. The analytical model accurately represents the dynamic response of the target under impact by a projectile. Different criteria for initiation of damage and plug formation were investigated and the damage initiation and progression in the target and its effect on the dynamic response were estimated. The model predicts the residual velocity of the projectile at the end of the penetration process. The predicted residual velocities show good agreement with the experimental residual veloctiies for a range of striking velocities near and above the ballistic penetration limits velocity of the target.