Research on vulnerability of tunnel structure subjected to near-fault and far-field ground motions
MEI Xiancheng1，2，CUI Zhen1，2，SHENG Qian1，2
(1. Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. University of Chinese Academy of Sciences，Beijing 100049，China)
Abstract：Regarding the control engineering of Sichuan-Tibet railway(Zheduoshan tunnel) as the research object，the dynamic time history analysis model is established. Combined with the site ground motion design response spectrum，the near-fault pulse-type ground motions and far-field ground motions are selected for the incremental dynamic analysis on the seismic performance of tunnel engineering structure. Then，a preliminary discussion of the seismic intensity index IM applicable to the tunnel structure is carried out，and the damage degree of the tunnel structure at different key locations is presented. Afterward，the seismic vulnerability probability of the tunnel structure under the action of the near-fault pulse-type ground motions and the far-field ground motions is compared and analyzed. The failure probability of the tunnel structure under the three-level fortification level under the action of two different ground motions is further presented. The results showed that PGA is a suitable IM index For the tunnel structure. The lining on the left and right side walls of the tunnel is vulnerable to earthquake damage，which can be regarded as the weak part for the seismic design. Under the level of VIII-degree frequent earthquakes，there is a high probability that the tunnel structure will only be slightly damaged or even remain intact and undamaged，while there is a greater probability that the tunnel structure will be serious damage to life and safety under the level of VIII-degree rare and extremely rare earthquakes. Under the same intensity of ground motions，near-fault pulse-type ground motions are more likely to cause more serious damage to the tunnel structure and have stronger destructiveness. Therefore，In the seismic design of tunnels，the impact of the velocity pulse effect of near-fault ground motions on the seismic performance of tunnel structures cannot be ignored.
梅贤丞1，2，崔 臻1，2，盛 谦1，2. 近断层/远场地震动作用下隧道结构易损性研究[J]. 岩石力学与工程学报, 0, (): 300-300.
MEI Xiancheng1，2，CUI Zhen1，2，SHENG Qian1，2. Research on vulnerability of tunnel structure subjected to near-fault and far-field ground motions. , 0, (): 300-300.
