Study on the Technology of Middle Column in Li-Jia-Ping Station of Chongqing Metro Line No.9

In order to study the construction technology of the underground excavation station of Chongqing where the geological conditions of the surrounding rock are better, Li-jia-ping Station of Chongqing rail transit line 9 is selected as the engineering background. On the basis of the traditional double sidewall tunnel method, the middle column method is proposed. Through the numerical simulation analysis of the variation of the tunnel dome subsidence, the horizontal displacement of the surrounding rock, and the plasticity of the surrounding rock under the construction of the spacer column method, the result shows that the construction of the middle pillar can satisfy the vault of Li-jia-ping station according to the field monitoring measurement data. Subsidence and surface subsidence control requirements. The research results can provide references for the design and construction of subway stations with large cross-section excavation under similar conditions.