Shockwave attenuation characteristics of rapid-assembly anti-blast walls under explosive load

This study focused on the anti-explosion performance of rapidly assembled modular blast walls under a 117.5 kg TNT explosion. The test recorded diffracted overpressure on the rear side of the wall, revealing a nonlinear spatial distribution of overpressure behind the wall. Under the combined effects of Mach reflection and wave system superposition, a secondary pressure peak occurred at a position 1.0 times the wall height behind the wall. A numerical model validated by experiments was established using LS-DYNA software to quantitatively analyze the influence weights and threshold effects of wall proportional height, proportional distance, and proportional thickness on protective effectiveness. For the first time, this study reveals the unique four-peak diffraction mechanism for this specific configuration, elucidating the local overpressure enhancement law induced by Mach reflection at 1.0 times the wall height behind the wall. By combining cranial injury criteria, the safe area behind the wall was qualitatively divided for this working condition. An empirical formula for predicting overpressure was established, comprehensively considering the coupling effects of TNT equivalent, blast wall geometric parameters, and distance behind the wall. The results show that the maximum overpressure reduction rate of this type of blast wall is 78.2%, and the average near-field protection effectiveness is approximately 1.76 times that of the far field. The research findings can offer valuable references and optimization strategies for protective structures against hundred-kilogram-level explosion impact.