Assessment of numerical modeling approaches for thin composite laminates under low-velocity impact

Low-velocity impact behaviors of carbon/epoxy composite laminates have been widely investigated in recent years by using various numerical modeling approaches in which the specific damage initiation criterion, damage evolution method and interface model were employed. However, the computation accuracies of these approaches have rarely been compared and reported. To explore a high-precision modeling approach for low-velocity impact behaviors of laminated composites, numerical study focusing on a comparison of different failure criteria (Hashin/Puck), evolution methods (sudden/linear/exponential) and interface models (zero-thickness cohesive elements/finite-thickness cohesive elements/cohesive contact) was conducted. The dynamic mechanical responses and damage behaviors predicted by different modeling approaches were compared. A new damage index DI was proposed to characterize the extent of damage accumulation in each layer of laminates. The results indicate that the impact responses of the material are more influenced by the evolution methods rather than the failure criteria. The numerical results predicted with Puck criterion, linear evolution method, and finite-thickness cohesive elements are in the best agreement with the experimental data.