大跨度钢桁拱桥设计关键技术  

Key Technique for Design of Long-span Steel Truss Arch Bridge

作　　者：孙亮 SUN Liang

机构地区：[1]中国市政工程中南设计研究总院有限公司,湖北武汉430010

出　　处：《城市道桥与防洪》2021年第4期61-64,共4页Urban Roads Bridges & Flood Control

摘　　要：柳州市白露大桥为主跨288 m的连续钢桁拱桥,采用两片主桁,主桁中心距为37 m。针对边跨桁梁桁高矮、横向宽度大的特点,将腹杆设计为变截面,通过减小其线刚度并增大截面面积的方法以消除横向框架效应产生的不利影响。平联采用较为简洁的菱形桁式,兼顾结构的受力合理性和美观性。桥面采用密横梁体系的正交异性整体桥面板,使桥面板参与主桁共同作用的同时避免了横梁面外弯曲。为改善结构气动性能,降低风致振动的影响,采用柔性吊杆。边跨平弦钢桁梁采用支架法半悬臂施工,中跨拱圈采用以临时墩辅助拱上吊机悬臂架设的施工方案,桥面系随主桁同步架设。Liuzhou Bailu Bridge is a continuous steel truss arch bridge with a main span of 288 m,using two main trusses with a center distance of 37 m.In view of the characteristics of the side span truss beam with low height and large transverse width,the web members are designed as variable cross-sections,and the adverse effects of the transverse frame effect are eliminated by reducing the linear stiffness and increasing the cross-sectional area.The relatively simple rhombus truss design is adopted in longitudinal connection,taking into account the mechanical rationality and aesthetic properties of the structure.The orthotropic integral bridge deck with dense beam system is adopted to avoid the out-of-plane bending of the beam during the interaction between the deck and the main truss.Flexible suspenders are adopted for the improvement of the aerodynamic performance of the structure and the reduction of influence of wind-induced vibration.The side-span flat-chord main truss is constructed with the bracket and semi-cantilever method.The construction plan of cantilever erection by arch crane with assistance of temporary piers is adopted for the middle-span arch ring,and the bridge deck is erected synchronously with the main truss.

关 键 词：桥梁工程 钢桁拱桥 大间距主桁 密横梁整体桥面 柔性吊杆 悬臂施工 

分 类 号：U448.22[建筑科学—桥梁与隧道工程]