Kinetic energy penetration phenomena are of interest in a variety of applications ranging from terminal ballistics to protection of spacecraft due to meteoroid impact, containment of high mass or high velocity debris due to accidents or high rate energy release, design of hardened protective facilities, erosion and fracture of solids due to impact,
The occurrence of multiple phenomena in the target such as localization, plasticity, anisotropic damage, fragmentation pushes the limits of existing modeling and computational capabilities for description of the target response. Since the deformation rates are very large an eulerian description coupled with a fluid-like model are suitable to describe the target. Fluid-type constitutive equations have been used to describe the high-strain rate behavior of metallic materials (e.g. Batra [
]). Implicit in these models is the hypothesis of incompressibility, hence those models cannot describe the irreversible volumetric changes observed in porous materials (e.g. geologic or cementitious materials).