Prediction of Low-Velocity Face-on Impact Response and Compression after Impact (CAI) of Composite Laminates using EST and Cohesive Modeling (DCZM)

摘要

In this paper a shell based finite element (FE) modeling technique is introduced for predicting the low-velocity impact response and compressive strength after impact (CSAI) of fiber reinforced polymer matrix composite (FRPC) laminates. The model combines the Enhanced Schapery Theory (EST) in-plane material model with discrete cohesive zone elements to model the important damage and failure mechanics of a laminate subject to impact and compression after impact (CAI). The model is shown to successfully capture the important failure modes observed in a variety of laminates with different lay-ups subjected to face-on impact. The shell modeling method is able to capture the global effects of through-the-thickness (or 3D) damage through the use of individual shell layers coupled with discrete cohesive elements. The model is compared against experimental results for both impact and CAI for a variety of laminates including traditional and non-traditional ply angles. The computational results were found to be in excellent agreement with experimental data. The virtual testing approach presented in this paper is most useful for sizing and selecting material in the preliminary design stage of aircraft structures because of its computational efficiency, yet being of sufficient fidelity.