Dynamic Failure of Foam-Reinforce Composite Lattice Sandwich Beam to Local Impulsive Load

Based on the Hashin 3D failure criteria, both stiffness degradation and interface delamination are adopted to model the damage evolution of the composites, a numerical study on the composite lattice sandwich and its foam-reinforce sandwich beams subjected to local impulsive load is performed to identify the effects of impulsive intensity and foam reinforcement on the dynamic response, failure modes, and energy absorption mechanisms. The numerical result is confirmed to have a great agreement with the previously experimental results. The results show the impact strength has a significant influence on the dynamic response, failure mode, and energy dissipation mechanisms of the beams. With the reinforcement of the foam, the composite sandwich beam undergoes a slower deformed response than the lattice sandwich beam, especially for the intensive loads. The compression and cracking of the foam core reduces the degree of failure and keeps the structural integrity, and at the same time effectively decreases the energy absorption ratio of other components, indicating a noticeable improvement of impact resistance of the foam-reinforce composite lattice sandwich beam to concentrated impact load.