ABSTRACT
Tunnels crossing inactive faults may suffer from severe damage during earthquakes. Fault sites have a significant hanging wall effect during earthquakes, but this effect on the tunnel seismic response has not been specifically quantified. In this study, shaking table tests were conducted to investigate the fault site effect and seismic response of fault-crossing tunnels. The hanging wall effect is the results of the geometric effect due to the asymmetric distribution of inclined fault. This geometric effect will lead to the reflection of seismic waves between the ground surface and fault interface and exacerbating the acceleration of the hanging wall. The acceleration of the tunnel located in the hanging wall is significantly greater than that located in the footwall, which is not only attributed to the dynamic characteristic of the site, but also the interaction between the dynamic characteristics of different areas of the site. For the tunnel sections located in the hanging wall, the influence range of the fault is approximately twice the tunnel diameter, for those located in the footwall, the fault has limited effect.
