Study of Tunnel Response to Seismic Loads Corresponding to Different Values of Depth and PGA

This paper presents a study of dynamic behavior of tunnels during earthquakes. The analyses are based on Finite Element Method (FEM) using PLAXIS computer program. Material properties for both soil and lining are assumed to be linear elastic. The effect of two major parameters including Peak Ground Acceleration (PGA) of earthquake and tunnel depth is paid attention at this study. The significant character of the correlation between PGA and the tunnel depth is the attenuation of motions with depth. The vulnerability of tunnel to earthquakes is investigated concentrating two mentioned factors based on motion attenuation ratios. Results indicate that shallow tunnels are more vulnerable to earthquake than deep tunnels considering both PGA and depth factors. Effects of both parameters reported in the literature, are also presented here for comparison and confirmation.

Keywords:

Dynamic Load , Variation of Motion , PGA , Tunnel Depth