Centrifuge Modeling of Underground Tunnel in Saturated Soil Subjected to Internal Blast Loading

A centrifuge test was carried out to investigate the response of transit tunnels in saturated soils under internal blast loading. A similar test with dry soil was conducted beforehand as a comparison. The tests were carried out with a centrifugal acceleration of 50 g to simulate the effect of blast loading from 150-kg trinitrotoluene (TNT) inside a transit tunnel of 5-m diameter. Exploded bridgewire (EBW) charges were employed as the model explosives, and the model tunnel was simulated by thin-wall aluminum tube. The model tunnels were significantly damaged by the projectiles that were part of the EBW charges. Soil liquefaction occurred in saturated soil with 150 kg of TNT exploded at approximately the center of the tunnel.