Earthquakes occurred frequently this century. The earthquake created an inestimable damage to tunnels and underground structures. Also, cracked lining widely exist in practical projects. Based on model test, the preliminary study to the seismic response rule of cracked lining tunnel had been conducted. The following conclusions can be obtained. Under the same rock pressure, the additional moment of hard rock is larger than for soft rock. The bigger the rock pressure is, the larger additional moment of structures will be. The additional moment of intact lining and cracked lining are relatively large in the direction of 45 degrees to the horizontal direction. When there is only one crack, the moment of the lining is reduced near the crack. When there are more cracks in the lining, the bending moment has stress concentration near the crack. The conclusion of these experiments can provide a reference for the designer.
Many tunnels have been damaged noticeably in earthquakes in last two decades including 1999 Chi-Chi, Taiwan earthquake (Wang 2001) and 2008 Wenchuan earthquake (Wang 2013). The response of tunnel lining was studied by shaking table (Yakovlevich 1987). Experiments were carried out on the underwater tunnel by means of the mechanical vibration (Shunzo 1984). The seismic response of two parallel shield tunnels were tested, and the influence of the parallel distance on the seismic response of the structures was studied (Goto 1988). Based on the investigation of earth-quake damage and seismic analysis, the characteristics of dynamic response of underground structure were summarized (Kuesel 1969). The basic rules of seismic damage of underground structures were summarized (Hashash 2001). In 1980s the flexibility ratio concept was introduced into the seismic research (St. John 1980). An analytical method for the interaction between structure and ground was proposed by scholars (Yousser 2001). However, study on seismic response of cracked lining is rare. In this paper, we analyze the seismic response of cracked lining by model experiment.
