Mitigation Effects of a Water Barrier on Dynamic Loads on the Human Body at Explosions in Tunnels

Abstract

According to the standards ISO 6184/4 and EN 14373, the efficacy of explosion suppression systems is estimated by maximum reduced (suppressed) shock wave overpressure, recorded in a suppressed explosion event. In addition to this, a significant interest is the capability of explosion protection systems to reduce the dynamic loads on the human body. This task is not considered in standards. The G. Tsulukidze Mining Institute has been studied mitigation of dynamic loads on human by water barrier, generated using the protective system. The system composed of a blast detector, a wireless device for activation and an absorber. During an accidental explosion, the proposed system immediately forms a protective water barrier in the zone to be protected to reduce the overpressure generated by a shock wave. A prototype model has been manufactured, installed and tested under real explosion conditions in the underground experimental base of the G. Tsulukidze Mining Institute. An anthropomorphic test device Hybrid III 50th was used during testing. To register dynamic load generated during an explosion, 7 sensors were installed in different zones of the dummy. Tests were conducted both with the use of the protective system and without it, in conditions when the charge weight was 2 kg, and the distance from the charge to the dummy was 8,5 m. Comparative analysis showed that the protective system, which contains one absorber (may contain several absorbers), reduces the dynamic loads generated in different zones of a human body by 30-50%.