{'fraction_non_alphanumeric': 0.01937046004842615, 'fraction_numerical': 0.0018159806295399517, 'mean_word_length': 5.357692307692307, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 1, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Numerical Simulations of Explosive Blast Pressures During Wall Breaching

During the past several years, the US Army has focused considerable attention toward developing improved methods for breaching walls and determining weapon-target interaction effects from direct- and indirect-fire weapons in the urban combat environment. A major thrust area is centered on developing methods for predicting the blast and fragmentation environment behind a breached wall. This information is important to the warfighter in terms of recognizing the expected impact on both enemy combatants, and non-combatants or friendly forces. One impediment to this effort is that little data exist to document the behind-wall blast environment produced by the detonation of explosives against or within walls. As part of the Army's effort, the US Army Engineer Research and Development Center (ERDC) is conducting experimental and numerical investigations to improve wall breaching methods. In the experimental and numerical programs, the ERDC conducts comprehensive research on a full range of urban construction materials. As a first step in this process, the ERDC conducted a baseline study of C-4 breaching effectiveness against steel-reinforced-concrete (RC) walls. A goal of this effort was to better define the behind wall blast environment produced by various C-4 charges placed in contact with RC walls. Numerical simulations of selected experiments were conducted using the coupled Eulerian-Lagrangian code Zapotec. In these simulations, the concrete and reinforcing steel were modeled as Lagrangian materials, and the C-4 and air were modeled as Eulerian materials