Blast performance of demining footwear: Numerical and experimental trials on frangible leg model and injury modeling

Abstract

This study reveals the protective efficacy of a personal protective boot against mine blasts both experimentally and numerically. By employing analyses conducted with the use of different amounts of explosives, the protective efficacy of the developed boot is compared to a typical military boot as reference. Both for analysis and verification tests, a ballistic gelatin covered frangible leg model was used. Strain energy that is exerted on the leg was determined with numerical analyses and verified with data obtained from strain gauges that were placed on the leg model. By employing the dynamic finite elements method, the physical injury that occurred to the leg model was examined and compared with the results of the blast test. The type-2 boot decreased the strain energy by approximately 80% compared with the type-1 boot. This observation was also verified with measurements obtained from strain gauge sensors placed along the tibia bone. It was observed that the damage occurring on the tibia bone was limited to local injuries and concentrated at a single spot without causing any fractures with the type-2 boot. As a result of axial load, the leg with the type-1 boot demonstrated fractures at several points rather than a fracture at a single point based on deflection. Hence, the latter case yields irremediable injuries.