Exelis Inc. performed a range of civil engineering computer-aided design (CAD) code development, integration, and assessment tasks dealing with counterproliferation ground targets on the Air Targets Lethality Analysis Program (ATLAP). The majority of the ground targets were heavily reinforced concrete underground facilities requiring the solid civil engineering background of Exelis Inc. personnel. Exelis Inc. performed risk identification/ analysis/mitigation studies on complex systems, including a nuclear power plant vulnerability assessment study. Exelis Inc. performed vulnerability assessments of the critical components in a pressurized water reactor (PWR) and G2 nuclear power plants that could be targeted by conventional weapons. Exelis Inc. conducted design studies and analyses by assessing the effectiveness of these weapons in inflicting the required levels of blast and fragment component damage to cause facility shutdown while minimizing the probability of collateral hazard. This work included the construction of artificial intelligence (using GO functional models) as well as the selection of threshold levels of fragment damage and/or explosive overpressure. Exelis Inc. developed multiple CAD models (using BRL-CAD) of counterproliferation targets and other facilities of interest including the above-mentioned nuclear power plants. Preliminary design details modeled included structural members, agent containers, production components, and ground surfaces. Exelis Inc. applied several codes to perform simulation and modeling tasks at the engineering code level as well as in using first principle finite element codes.
d) Exelis Inc. completed end-to-end assessments of real-world foreign targets and notional targets in performing risk identification/analysis/mitigation studies. Exelis Inc. simulated the synergistic blast and fragment loading from a BLU-109 on a reinforced concrete wall using the K-DYNA3D finite element code. Computational results compared well with the observed damage in the experiment. Exelis Inc. also characterized the penetration effectiveness of Mk-82 and Mk-84 conventional weapons to perforate the pressure vessel of a nuclear power plant using K-DYNA3D. Both of these efforts utilized Exelis Inc.'s concrete material model and sliding interface methodology added to DYNA3D by Exelis Inc.
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Exelis Inc. supported test operations in the Air Targets Lethality Analysis Program. Exelis Inc. developed the ARM, IDV, HER, CVAR and WolfPac CP codes for simulation and modeling to test concept feasibility; we used these codes to perform pretest predictions of AFRL and DTRA sponsored tests. On the Heavy Cased Warhead Lethality Tests, K-DYNA3D finite element calculations were performed simulating the synergistic BLU-109 blast and fragment loading on a reinforced concrete wall at the close range of four feet. Exelis Inc. generated a set of fragment loading time histories based on BLU-109 arena test data and applied these histories to the virtual test model as intense pressure spikes in the statistically proper location and at the proper time. Computational results compared well with the observed damage in the experiment.
In another effort, Exelis Inc. again used K-DYNA3D with material models 16 and 37 as a part of the Defense Special Weapons Agency (DSWA) (now DTRA) precision test modeling (PTM) tunnel response effort. For this project, Exelis Inc. modeled a BLU-109 detonation above a tunnel free surface in limestone. The volume of expected debris on the floor of the tunnel was compared to similar experimental results. In other tasks Exelis Inc. performed independent verification of vulnerability analyses on the DSWA Dipole Jewel test scenario and also for a Nuclear Power Plant vulnerability assessment study. Exelis Inc. performed vulnerability assessments of the critical components in each of the above mentioned counterproliferation target classes. This included classes that can be targeted by conventional weapons and the effectiveness of these weapons inflicting the required levels of blast and fragment component damage to cause facility shutdown or while minimizing the probability of collateral hazard (radioactive or chem/bio agent release). Overall, this work involved the construction of artificial intelligence (GO code) functional models; development of a BRL-CAD computerized physical target model; selection of threshold levels of fragment damage and/or explosive overpressure. This work clearly demonstrates Exelis Inc.'s strong civil engineering test and evaluation capabilities in the areas of non-linear finite element analysis, knowledge of concrete constitutive and equation-of-state models, nuclear power plant functional modeling, CAD drawing review, and an understanding of concrete/geologic penetration resistance.
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