Abstract: A deep excavation is adjacent to the planned subway section and is supported by soldier piles and double row cement mixing columns outside the soldier piles. By using MIDAS/GTS NX, the numerical analysis was conducted to study the impact of the deep excavation on subway sections and the impact of the subway section construction on existing building structures. The analytical results indicated that, when the proposed project is started after the completion of the subway section construction, the maximum horizontal displacement of the subway section structure towards the deep excavation direction is 8.8mm and the maximum settlement is 6.6mm; When the proposed project is completed before the subway section, the tunnel construction causes minimal deformation of the deep excavation support structure and surface. In both cases, the tunnel structure is safe, but in the first case, the displacement of the subway structure is close to the warning threshold value. To reduce the impact of the excavation on the subway structure, the excavation of the foundation must be constructed before the interval structure of the rail transit line construction, otherwise the supporting method should be changed. Before the construction of the deep excavation, numerical simulations can be used to analyze the impact between the deep excavation support and the adjacent subway shield interval, in order to evaluate the adequacy of the design and construction plan.

Key words: Large Deep Excavation, Numerical Analysis, Subway Sections, Displacement