Tunnel behaviour under seismic loads: Analysis by means of uncoupled and coupled approaches

K0 = 0.6. The water table is assumed at the ground surface.

A circular tunnel, located at a depth of 15 m and characterised by a 10.10 m diameter is selected as the reference underground structure for the present study. The lining is assumed to be composed by 0.50 m thick precast concrete segments characterised by the following parameters: Young’s modulus El = 38 GPa, Poisson’s ratio νl = 0.25, damping ratio Dl = 5%.