Longitudinal Nonlinear Seismic Response of Shield Tunnel Based on Generalized Response Deformation Method

The Sanyang Yangtze River Shield Tunnel in Wuhan is selected for the research. The precise beam spring model of the shield tunnel is established, and considering the nonlinearity of soil, the longitudinal seismic response analysis of the shield tunnel is carried out based on the generalized response displacement method. The maximum opening width at ring intersegment and the internal force distribution of the pipe ring along the longitudinal direction are presented with different intensities and frequency spectra of earthquake motions. The results show that the uneven distribution of the terrain and the soil layer has an important influence on the opening value and the internal force of the pipe rings. Due to that the bedrock with larger stiffness is set and the constraint of silty-fine sand with relatively small stiffness to tunnel is smaller, a sudden change of the opening value is obvious at the intersection of bedrock and silty-fine sand.