Research on Excavation Techniques of Big Cross-section Shield Tunnel

With construction of big cross-section and super cross-section shield tunnel,the problems are more and more prominent in shield tunnel excavation.Connecting the excavation of Nanjing Yangtse Rive shield tunnel,the paper analyzes the excavation parameters influences and hurt on tunnel construction quality and shield segment uplifting,including hydraulic pressure on cross-section,shield shell excavation speed,synchro concrete mortar injected,ect.,and then offers some corresponding excavation measures.