Abstract:The current status of research on liquefaction failure in underground structures is not ideal. It is necessary to analyze the soil liquefaction potential of underground structures such as subway tunnels. In this paper, the anti-liquefaction safety of the Taiyuan metro tunnel was analyzed using four methods, i.e., those used by Tokimatsu and Yoshimike, Seed, the Japan Road Association, and the Chinese code. The overall liquefaction risk level of the site was evaluated. Based on the dynamic shear-stress ratio of vibration liquefaction, the anti-liquefaction safety factor, the relationship between the standard penetration test number and volumetric strain, and the liquefaction settlement deformation of the shield tunnel were evaluated. By the adoption of the anti-liquefaction technique of secondary grouting of the shield tunnel in silty sand and the clay silt stratum, it is suggested that secondary grouting of a cement-based suspension be used to reinforce the foundation of the Taiyuan Metro to improve its anti-liquefaction ability and reduce the deformation associated with liquefaction-induced settlement.
