Depth of penetration of steel-tube-confined concrete targets based on dynamic finite cylindrical cavity-expansion models

Abstract

Steel-tube-confined concrete (STCC) targets show excellent anti-penetration performance as a result of confinement effect of steel tube on in-filled concrete. A dynamic finite cylindrical cavity-expansion (FCCE) model with elastic radial spring was developed to analyze the confinement effect and predict the depth of penetration (DOP) of STCC targets normally penetrated by rigid sharp-nosed projectiles. Firstly, steady responses of the dynamic FCCE approximation model were obtained on the basis of the assumption of incompressibility of target concrete and failure of comminuted zone with the Heok–Brown criterion. Then, based on the dynamic FCCE approximation model, a DOP model for STCC targets impacted by rigid projectiles was proposed. Lastly, the penetration tests of STCC targets normally penetrated by 12.7 mm armor piecing projectile (APP) were taken as examples to validate the applicability of the dynamic FCCE approximation model and DOP model. The results show that in comparisons with the results based on the dynamic spherical cavity-expansion (FSCE) model, the DOP model based on the dynamic FCCE model in this paper is more applicable to predict the DOP of STCC targets penetrated by rigid conical or other sharp-nosed projectiles with a proper value of empirical constant m in the Heok–Brown criterion.