Mitigation of Blast Effects on Underground Structure Using Compressible Porous Foam Barriers

Abstract

Explosions on the ground surface induce strains on underground structures, such as tunnels and pipelines. Depending on the size of the explosion, distances involved, and the nature of the intervening material, these strains can be relatively high, thus causing severe damage to the structure. Barriers may be used to protect a structur, by reducing the strains created as a result of the explosion. The role of compressible protective barriers (made of polyurethane foam) and rigid barriers (made of concrete) in reducing the impact of a surface explosion was studied. Results of physical model experiments conducted on geotechnical centrifuge are presented and analyzed to evaluate the effectiveness of different types of barriers. Numerical model analyses were also conducted to further understand the behavior of different types of protective covers as compared to a soil cover. Results of such studies can help design barrier systems capable of mitigating effects of explosions, thus protecting essential components of underground infrastructure.