Blast Resistant Armor Appliqués

Armors that provide protection against blast do so through a number of mechanisms. Simple elastic mechanisms include reflection of the blast wave because of the armor's high impedance relative to air, and distribution of energy over a large area by wave propagation through the armor. Non-linear effects, such as plasticity and damage evolution, enhance the armor's effectiveness by dissipating mechanical energy. The goal of the work proposed here is to develop armor that utilizes "waiting elements," a concept that research suggests is capable of increasing the energy dissipated by plastic deformation or fracture. Waiting elements were proposed and studied by Professor Andrej Cherkaev, at the University of Utah, and his colleagues. Much of his mathematical analysis has been with lump-parameter models. The force-elongation behavior of the non-linear springs governs the dissipation of the material. Our goal is to transition the concept into practice. In Phase I we first create several armor concepts that seem feasible in terms of manufacturing. We then rely on finite-element methods and lumped-parameter models to predict the response of these concepts to blast, and to conduct parametric studies of their performance.