Mechanics of integral armor: discontinuous ceramic-cored sandwich structure under tension and shear

Abstract An integral armor sandwich structure consisting of S2-glass-reinforced face sheets with adhesively bonded discontinuous ceramic tiles provides potential optimal ballistic protection and structural performance at minimum weight for composite armored vehicle applications. The structural response is investigated by defining an idealized unit cell subjected to tensile and in-plane shear membrane loading. In the model, an admissible stress system that satisfies equilibrium and all boundary and interface conditions is constructed, and the principle of minimum complementary energy is employed to find an optimal approximation. Typical stress variations are presented, and their implications for progressive damage and failure of the structure are discussed. Based on the stress and deformation fields in the core and face sheet, the overall effective stiffness of the structure can be evaluated. By selecting some critical parameters, such as the core length and the adhesive stiffness and thickness, an optimized design for the structure can be achieved.