Blast wave mitigation from a straight tube using metal foam floor plate

Abstract

Blast wave mitigation from a straight tube using a metal foam plate (MF) was evaluated to examine effects of such a plate on a tube floor by measuring the blast pressures outside the tube. MF were installed on the floor of a straight, 330-mm-long square tube with a 30×30 mm² cross-section. The 5-mm-thick MF layer did not contact the test explosive. One tube end was closed. A specially designed small detonator that contained 100 mg lead azide was ignited near the closed tube end as the test explosive. The MF mitigated the blast wave. The MF, installed for whole length, absorbed approximately 40 % of the explosive energy. The results underscored that specially designed materials and a tube or tunnel interior surface structure can mitigate blast pressure remarkably.