Abstract:At present, analyses of seismic damage to tunnels have focused on the tunnel portal and portal section.However, there are still many deeply-buried tunnels that have been badly damaged by earthquakes;an important reason for this is the existence of voids behind the lining or because the lining backfill is not dense.However, studies on the relationship between voids behind the lining and the dynamic characteristics of earthquakes are few.In this study, the seismic performance of a tunnel with voids behind the lining are studied using the finite element software ABAQUS.The analysis reveals the following:if the lining is tightly and firmly stuck to the surrounding rocks, even under larger seismic action, the lining remains in a good state of compression.Once voids are present behind the lining, the lining that does not have the support of the surrounding rock comes under great tensile stress, resulting in cracking of the lining, which causes tunnel collapse.In addition, during earthquakes, larger plastic deformation appears in the surrounding rock without lining support than in those with lining support, causing the rock to more easily relax and fall off.
