Abstract:
There aren′t many project cases of shallow large-span tunnel metro stations in rock strata that are soft on top and hard on the bottom, nor is there referential experience for a reasonable structure type and construction method for these metro stations. Based on the Xinggongjie Station of the Dalian metro, a new structure type and construction method named“stacked loaded arch for metro stations”is presented by analyzing the characteristics of loose surrounding rock of a large-span tunnel in upper-soft and lower-hard stratum, and similar project cases. So a single-arch station structure with a span of more than 20 m can be constructed. The design method and mechanical characteristics of the initial support and secondary lining for a stacked loaded arch structure are analyzed. Application practice shows that the stacked loaded arch with initial support bears the full load in the construction process,the lower structure can be built safely under its protection, ground deformation can be controlled effectively and rapid mechanization construction in rock stratum is feasible.
.Structural Design of the Stacked Loaded Arch of Large-Span Tunnels in Upper-Soft Lower-Hard Rock Stratum[J] MODERN TUNNELLING TECHNOLOGY, 2018,V55(1): 17-26