地铁车站与立交桥施工顺序对车站主体结构的影响研究

针对太原地铁西涧河车站和立交桥实际工程案列，为了探明二者施工顺序对车站主体结构楼板、车站框架柱的受力与变形的影响。运用大型有限元软件MIDAS/GTS建立精细化的三维模型，模拟“先桥后站”与“先站后桥”施工全过程，分析主体结构楼板及格构柱的力学特性。结果表明:底板竖向位移对站桥的施工顺序较中板和顶板更为敏感，“先桥后站”底板位移显著小于“先站后桥”施工的底板位移，两种方案施工下中板、顶板变形均表现为格构柱处隆起，柱点周围下沉；两种施工顺序下车站底板弯矩差别最大，顶板次之，中板变化最小，施工顺序对底板横向弯矩、纵向弯矩差异百分比分别为88.41%，89.73%；“先桥后站”格构柱的受力及变形均小于“先站后桥”施工工序，其中变形更加敏感，格构柱最大水平位移的差异百分比达到53.02%。

Study on Influence of Construction Sequence of Subway Station and Overpass Bridge on Main Station Structures

The actual project case of Xijianhe Station and the overpass of Taiyuan Metro was depended to find out how their construction sequence influenced the stress and deformation of the main station structures, such as the floor and the frame columns. A fine 3D model was established with large-scale finite element software MIDAS/GTS to simulate the construction process of ‘bridge first then station’ or ‘station first then bridge’, and analyze the mechanical properties of the floor and lattice column. The result shows that, compared to the middle and top plates, the vertical displacement of bottom plate is more sensitive to the construction sequence of station and bridge; the displacement of bottom plate in ‘bridge first then station’ is less than that in ‘station first then bridge’ obviously and, in the both cases, the middle and top plates deform with uplift at the lattice column and subsidence surrounding the column point; in the both sequences, the maximum difference of bending moment occurs at the bottom plate, the second is the top plate, and the minimum at the middle plate, for the bottom plate, the percentage difference of its transversal and longitudinal bending moments against the sequence are 88.41% and 89.73%, respectively; both the stress and deformation of lattice column in ‘bridge first then station’ are less than those in ‘station first then bridge’, wherein the deformation is more sensitive, and the percentage difference of maximum horizontal displacement of the lattice column reaches 53.02%.