Impact Investigation Using Ansys Autodyn Code on a Reinforced Concrete Model Due To TNT Shaped Charge for Nuclear Security Vulnerability Assessments

Abstract

The objective of this study is to predict the damage that could be created on a reinforced concrete wall due to the impact of Tri-Nitro Toluene (TNT) shaped charge using a numerical simulation software. There are many commercial numerical simulation software that can be used to solve engineering problems in real world scenarios, such as ANSYS, ABAQUS, LS-DYNA, etc. ANSYS Simulation Software is one of the strongest and user-friendly commercial finite element analysis (FEA) tools that uses computer-based numerical techniques. In this study, two different types of simulation software codes which can be coupled for the advanced analysis are used within ANSYS Simulation Software system. One is ANSYS Explicit Dynamic STR (Structure) software and the other one is ANSYS AUTODYN software. ANSYS Explicit Dynamic STR software provides suitable solutions of nonlinear dynamic events for a short duration, including a drop and impact testing with low velocity or high velocity, deformation by high pressure, explosion, etc. ANSYS AUTODYN software also provides suitable solutions of nonlinear dynamic events similar to ANSYS Explicit Dynamic STR, but this software is focused on complicated nonlinear dynamic events like high explosions and detailed damage responses of materials such as cracks and fragments. The reinforced concrete wall target is located at a distance of 50 meters from a TNT shaped charge design. Various TNT shaped charge designs are studied by changing the amount of TNT and liner fragment thickness, etc. in order to make the hole-size big enough on the concrete wall target so that at least a person can pass through it at a time. In addition, a physical protection system vulnerability assessment is performed with a hypothetic nuclear research reactor assuming that TNT shaped charge is used in order to reach to a desired target from the offsite to the nuclear research reactor. The probability of interruption (PI) is calculated with the Adversary Sequence Diagram (ASD) using Estimate of Adversary Sequence Interruption (EASI) model to conduct the vulnerability assessment, which provides the most vulnerable paths to reach to the target while minimizing time delay (tD) and the probability of detection (PD).