Calculations of Impacts into Concrete Targets Using the Holmquist-Johnson-Cook Model

Abstract

The Holmquist-Johnson-Cook (HJC) concrete model has been implemented in the EDEN hydrocode and applied in studies investigating the normal impacts of simple projectiles against finite thickness concrete barriers. The results of these calculations have been used to investigate how the loading on the projectile and the residual velocity varies as a function of the projectile speed and barrier thickness. Results from the simulations are compared against predictions from cavityexpansion theory based engineering models for projectile penetration, such as those due to Li and Chen, and Forrestal. Special attention is paid to the roles that release waves from the barrier’s back surface play in the process and further comparisons are made to investigate how well the extended model of Sjol and Teland is able to account for these effects. An empirically-derived release model is derived and applied to predict penetration data.