城市轨道交通单线连续U梁设计

以济南市轨道交通1号线工程为依托,对城市轨道交通单线连续U梁进行精细化设计。单线连续U梁为国内轨道交通项目的首次应用,采用三跨连续结构,主跨45 m,主桥全宽仅5.6 m,最小曲线半径795 m,设计难度较大。设计方案将连续结构体系与标准U型梁相结合,在标准U型梁断面的基础上对支点断面进行改造,使单线连续U梁外形与1号线标准U型梁一致,造型美观,可很好地解决外形顺接问题。单线连续U梁由于桥梁宽度小、跨度大,且位于较小半径曲线上,受力复杂,需要进行专门研究。通过建立全桥杆系模型与三维有限元模型,对结构进行整体静力分析及空间应力分析研究,探讨U型梁的基本力学性能和设计方法,为今后类似工程的设计提供参考案例。

The Design of Single-line Continuous U-beam Bridge for Urban Rail Transit

This paper is based on the Jinan Rail Transit Line 1, and conducts a detailed design of a single-line continuous U-beam bridge for urban rail transit. The single-line continuous U-beam bridge is first applied to a domestic rail transit project. The three-span continuous structure is adopted, with a main span of 45 m, a full width of only 5.6 m, and a minimum curve radius of 795 m, which impedes design. The design combines the continuous structure system with the standard U-beam and transforms the fulcrum section based on the standard U-beam section. Thus, the shape of the single-line continuous U-beam is consistent with the standard U-beam of Line 1. It shows an attractive appearance and solves the problem of smooth shape. The single-line continuous U-beam has complex mechanical properties that require special research owing to the small width, large span, and small curve radius of the bridge. By establishing the beam element model and three-dimensional finite element model of the entire bridge, the overall static and spatial stress analys of the structure were conducted, and the basic mechanical properties and design methods of the single-line continuous U-beam were discussed, providing a reference case for the design of similar projects in the future.