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NUMERICAL MODELING OF HIGH-VELOCITY, PROJECTILE PENETRATING CONCRETE BLOCKS REINFORCED BY TEFLON SHEETS

Recently, the concern about protecting people and structures has increased due to the increasing number of terrorist attacks. This paper presents a numerical simulation of plain concrete blocks with an unconfined compressive strength of 35 MPA, reinforced by Teflon sheets and subjected to ballistic impact by a high-velocity rigid projectile (960 m/s). The reinforcement sheets are modeled with different thicknesses and located at different depths from the face of the concrete target. The Teflon material was chosen due to its high impact strength over a wide range of temperatures. A validation model was conducted and results showed a good agreement with previous experimental results. The investigation presents the development of a finite element accurate model using AUTODYN 3D. The Lagrangian formulation numerical technique is used to model both the projectile and the concrete target. The main findings showed an enhancement in the penetration resistance of concrete target when reinforced by Teflon sheets compared to the concrete resistance without reinforcement, where the projectile depth of penetration was reduced by 64.8% and the full damage depth of the concrete target was also reduced by 58%, which demonstrates the great performance of the chosen reinforcement in the shock wave propagation.