3 × 225 m三跨下承式连续钢箱系杆拱桥总体设计

Overall Design of 3 × 225 m Three-span Through Continuous Steel-box Bowstring Arch Bridge

摘要:

丹江口市水都二桥是丹江口市跨汉江的重要过江通道，按照城市主干路标准建设。为满足通航等技术标准，并考虑结构体系的合理性、周边城区环境的限制及投资的经济性，其主桥采用了计算跨径3 × 225 m的三跨下承式连续钢箱系杆拱桥。具体构造方面，其主拱采用变高度单箱单室矩形截面钢箱拱肋，拱轴线采用二次抛物线，主梁采用“钢格子梁+正交异性钢桥面板”，吊杆采用钢绞线整束挤压拉索体系。桥梁施工方法采用“主梁分段顶推+边段拱肋原位拼装+中段拱肋整体提升”。桥梁的设计、施工总体思路可供同类工程参考。

Abstract:

The Shuidu Second Bridge is an important passage across the Han River in Danjiangkou City, and is constructed according to the standards of urban main roads. In order to meet technical standards of navigation, and considering the rationality of the structural system, the limitations of the surrounding urban environment, and the economic feasibility of investment, the main bridge is designed as a 3 × 225 m three-span through continuous steel-box bowstring arch bridge. In terms of specific construction, the main arch is made of variable height single-box single-chamber rectangular-section steel box arch ribs, the arch axis adopts a quadratic parabola, the girder is used of a “steel grid beam+orthotropic steel bridge deck”, and the suspension rod is used of a whole bundle extruded cable system of steel strands. The "segmented pushing of the girder + in-situ assembly of the side arch ribs + overall lifting of the middle arch ribs" method is used for the bridge construction. The overall design and construction concept of the bridge can provide reference for similar projects.