Assessment of Soil Tunnel Interaction in Sand Soil

Abstract

In this study, series of shaking table tests were carried out to investigate the effect of tunnel model depth and direction of ground acceleration on the ground surface settlement and the dynamic earth pressure on the tunnel wall. Box tunnel model is embedded in dry and saturated soil (Karbala Sand). It subjected to three input sinusoidal motions 0.05g, 0.1g, and 0.2g. Two relative densities were used, 30% for the upper layer and 70% for the lower layer. The results obtained indicate that the settlement of soil surface increases with an increase in ground acceleration. The increase in tunnel model depth leads to an increase in settlement especially at 0.2g earthquake loading (for saturated and dry soil). The change of direction of seismic loading leads to a small change in the settlement for dry soil. The results appear that dynamic earth pressure (DEP) was positive in dry soil and negative in saturated soil in all test. In saturated soil, the effect of direction of ground acceleration and depth of tunnel model on DEP in 0.2g is quite little.