Finite element analysis of tile-reinforced composite structural armor subjected to bending loads

Composite structural armor (CSA) is a multi-functional structure that provides ballistic protection, stiffness and strength at minimum weight. It consists of a multi-layered architecture of polymer composites, rubber and ceramic tiles, stacked in a precise manner to obtain optimal ballistic performance. In the present work, the finite element method is used to conduct a detailed analysis of the mechanisms of load transfer and deformation of CSA subjected to bending loads. The results from two modeling approaches (three-dimensional and two-dimensional simulations) are compared to assess the accuracy of the computationally efficient two-dimensional model. The calculated deflections and surfaces strains from both models are found to agree very well with experimental results. The stress transfer between the layers is further analyzed using the two-dimensional model and the resulting through-thickness strain and stress distributions are discussed. It is found that the deformation of this multi-layered construction is complex and dependent upon the mechanism of stress transfer between the outer surface layer and the ceramic tiles. The effect on non-linear behavior of the constituent materials is investigated. The gap filled with polymer that separates adjacent ceramic tiles is shown to significantly influence the stiffness and strength of CSA. It is found that the plastic deformation of the resin corresponds to the onset of non-linear structural response. [Copyright &y& Elsevier]