南京仙新路长江大桥主桥结构设计  

Structural Design of Main Bridge of Nanjing Xianxin Road Changjiang River Bridge

作　　者：肖海珠[1] 高宗余[1] 陆勤丰[1] 唐贺强[1] 于俊杰[1] XIAO Haizhu;GAO Zongyu;LU Qinfeng;TANG Heqiang;YU Junjie(China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430056,China)

机构地区：[1]中铁大桥勘测设计院集团有限公司,湖北武汉430056

出　　处：《桥梁建设》2024年第2期1-7,共7页Bridge Construction

基　　金：江苏省交通运输科技项目(2019Y44)。

摘　　要：南京仙新路长江大桥主桥为跨径1760 m的单跨钢箱梁悬索桥,主缆垂跨比1/9,边跨跨径580 m,边中跨比0.33。该桥上、下游各设1根主缆,单根主缆由169股127∅5.4 mm镀锌铝高强钢丝索股组成,采用PPWS法施工,钢丝标准抗拉强度2100 MPa。吊索与索夹采用销接式结构,跨中设置柔性中央扣索,短吊索设置关节轴承。主索鞍采用宽鞍槽单纵肋铸焊结合构造,散索鞍采用底座式全铸结构。加劲梁采用扁平流线型封闭整体钢箱梁,总宽31.5 m,梁高4 m,顶板与U肋之间采用双面埋弧全熔透焊接。桥塔采用门形混凝土结构,总高277.3 m,其上横梁为预应力混凝土结构,外包N字造型钢结构;桥塔基础采用直径2.8 m钻孔灌注桩。南锚碇采用外径65 m圆形地下连续墙基础;北锚碇采用沉井基础,平面尺寸70 m×50 m,高50 m。对结构进行静力分析及抗风性能理论和试验研究,结果表明:结构强度、刚度均满足规范要求;在加劲梁上设置0.67 m高中央稳定板、两侧风嘴处设置1 m宽水平稳定板后,大桥的颤振、涡振等抗风性能均满足要求,且具备一定的阻尼储备。The main bridge of Nanjing Xianxin Road Changjiang River Bridge is a suspension bridge with a suspended main span of 1760 m and two side spans of 580 m,leading to a sag-to-span ratio of 1/9 and a side span-to-central span ratio of 0.33.The two main cables(an upstream and a downstream cables),each composed of a number of 169 high-strength galvanized aluminum steel wire strands(an individual strand contains 127 steel wires of 5.4 mm diameter and gets a nominal tensile strength of 2100 MPa),were constructed by the PPWS(prefabricated parallel wire strands)method.The hanger cables are pin-connected with the cable clamps,central buckles are added at midspan,and the short hanger cables are fitted with joint bearings.The tower-top saddles are cast-weld composite structures with wide grooves and single longitudinal rib,while the splay saddles are pedestal-type fully-cast structures.The stiffening girder,measuring 31.5 m in full width and 4 m in depth,consists of flat streamlined closed steel boxes,inside which,the top plates and U ribs are joined by double-sided submerged arc full-penetration welding.Supported by bored piles of 2.8 m diameter,the pylons are portal-frame concrete structures rising 277.3 m(full heights),the upper crossbeams are prestressed concrete structures encased with N-shaped steel plates.The south anchorage is mounted on a circular diaphragm wall foundation with an external diameter of 65 m,while the north anchorage is supported on a caisson foundation measuring 70 m by 50 m,50 m in depth.According to the static analysis,theoretical analysis of the wind resistance of the structure,and experimental studies,the strength and stiffness of the structure meet the requirements.Adding 0.67 m-deep central stabilizers and 1 m-wide horizontal stabilizers at the wind fairings allows the flutters and vortex-induced vibrations of the bridge to reach the required levels and the bridge has a degree of damping margin.

关 键 词：悬索桥 高强钢丝 索鞍 钢箱梁 地下连续墙 锚碇 抗风性能 结构设计 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] U442.5[交通运输工程—道路与铁道工程]