Sandwich plates with gradient lattice cores subjected to air blast loadings

The dynamic responses of multi-layer gradient pyramid lattice sandwich plates subjected to blast loadings were investigated by employing numerical simulation method in this paper. The relative densities of core layers were adjusted by varying cross-sectional dimensions of lattice truss. Six kinds of gradient configurations were proposed based on the arrangement of various lattice core layers. The mechanical properties of 304 stainless steel used in this analyses were simulated using rate-dependent JC constitutive model, and the blast loadings were imposed to the sandwich structures using CONWEP loading mode. The validation of the simulation approach was studied by a comparison of simulation results with the existing experimental results from the literature. The back sheet deflection and the support reaction were analyzed to evaluate the blast resistance of multi-layer gradient sandwich structures. It can be found that the gradient configuration, of which relative density of core layer increases layer by layer from front sheet to back sheet, has the most excellent blast resistance. The dynamic response of gradient lattice sandwich structures in the case of different standoff distances and different explosive charges were calculated. And the relationships between intensity of load and blast resistance of the gradient sandwich structures with pyramid lattice core were analyzed.