Modeling of impacts on composite structures

Impacts of foreign objects on composite structures can create internal damage that reduces the strength of the structure significantly. The study of such impacts requires understanding the dynamics of the event, predicting the extent of the induced damage, and estimating the residual properties of the structure. The impact event involves the motion of the target, the motion of the projectile, and the local indentation in the contact zone. A large number of parameters affect the impact dynamics, many types of responses can be obtained, and many models have been proposed in the literature. These models can be classified into three categories: (1) energy-balance models that assume a quasi-static behavior of the structure; (2) spring-mass models that account for the dynamics of the structure in a simplified manner; (3) complete models in which the dynamic behavior of the structure is fully modeled. Simple models can bring insight into the problem and be efficient but have limited applicability. Complex models may have wider applicability but require significantly higher modeling and computational effort. There is a need for a general understanding of the impact dynamics and for a method for developing efficient and accurate models.