独塔双层钢桁梁斜拉桥结构设计分析

Analysis on Structural Design of Single-pylon Double-deck Steel Truss Beam Cable-stayed Bridge

摘要:

独塔双层钢桁梁斜拉桥结构性能优越，双层通车，通行效率高，经济性好。以某工程项目为列，桥梁跨径布置为82 m+138 m+116 m，空间双索面，塔高99 m，主梁采用N形桁，桁高9.5 m，节间长度11.5 m，横向设置三片桁，中心距17.75 m；上下层桥面板均采用14 mm厚正交异性板。主塔采用弧形门式钢-混凝土混合塔，下部为实体混凝土结构，上塔柱为钢结构，中间为钢混结合段。利用有限元软件对结构进行了总体计算分析及局部受力分析，并对施工关键工况下桥塔转体进行了验算分析，保证结构受力安全性和经济性。

Abstract:

The single-pylon double-deck steel truss beam cable-stayed bridge has superior structural performance, double-deck traffic, high traffic efficiency and good economy. Taking a project as an example, the layout of bridge span is 82 m + 138 m + 116 m with the spatial double cable plane, the pylon height is 99 m, the girder is in N-shaped truss, the truss height is 9.5 m, the internode length is 11.5 m, and three trusses are set horizontally with a center distance of 17.75 m. The upper and lower bridge decks are all 14 mm thick orthotropic plates. The main pylon is a curved portal steel-concrete composite pylon. The lower part is a solid concrete structure, the upper pylon column is a steel structure, and the middle part is a steel-concrete composite section. The overall calculation analysis and local stress analysis of the structure are conducted using finite element software, and the verification analysis of the key construction condition, namely the rotation of the bridge pylon, is conducted to ensure the structural stress safety and economy.