The Effect of Steel Fiber Reinforced Concrete Panel Under the Penetration of High-Speed Projectile

In this paper, modeling of high speed projectiles with different nose shapes, penetrating into steel fiber reinforced concrete is investigated. Numerical simulation is used using LS-DYNA cod capabilities with Lagrangian method and axial symmetry form. The projectiles have an approximate mass of 45 (gr) and their velocities are about 2500 (m/s) penetrating into steel fiber reinforced concrete panel with volume fraction of 1.0%, 1.5% and 2.0%. In this article the exact behavior of steel fiber reinforced concrete confronting metallic projectiles at high speed is predicted. Here, Elastic-Plastic Hydrodynamic material model is used for prediction of projectile behavior. Also, the Mie-Gruneisen state of equation is employed for the relationship between the volumetric strain, hydrostatic stress and modulus of bulk at high velocity. The results of the simulations are compared with experimental work of other investigators and, the results show that ogive nose projectiles are more efficient than other projectiles. In other words, by increasingthe projectile length to diameter ratio from 0.5 to 0.9, for flat, hemispherical and ogive projectiles their residual velocities are increased. Also, it is shown that by increasing the volume fraction of steel fibers in concrete matrix, damage of top surface damage is reduced dramatically. The most important innovations of the present study is effect the steepness and length to diameter ratio projectile on the ballistic performance of the projectile and the effectiveness of use of steel fibers in concrete panels that increase the efficiency of passive defense.