摘要
武汉青山长江公路大桥主桥为主跨938m的双塔双索面钢箱及钢箱结合梁斜拉桥,桥梁全宽48m。桥塔采用无下横梁A形混凝土塔,塔高达279.5m,桥塔基础采用大型空心系梁哑铃形承台+钻孔桩的结构形式。斜拉索采用1 860MPaΦ7mm高强度锌铝合金镀层平行钢丝。为应对大跨、宽幅、重载交通带来的挑战,对该桥的抗风、抗震技术进行了重点研究。采用双索面A形塔及封闭箱梁断面以提高结构的抗风稳定性,通过风洞试验对构造细节进行优化以确保桥梁抗风安全。采用全飘浮结构综合约束体系,使得桥梁具有良好的静、动力性能,保证大桥在地震下的安全。针对宽幅桥梁的受力特点进行了详细研究,在此基础上对局部板件进行加强、设置横梁预拱度,并对宽幅钢梁制造与安装提出了指导意见和要求。对正交异性桥面板构造细节进行优化并采用合理的钢桥面铺装方案,保证了桥梁在重载作用下良好的结构性能。
The main bridge of Qingshan Changjiang River Highway Bridge in Wuhan is a twopylon cable-stayed bridge.The bridge has a main span of 938 m,with full deck width reaching 48 m.The A-shaped concrete pylon with no lower cross beam rises 279.5 mand rests on large dumbbell-shaped pile caps that feature the hollow tie beams and mounted on bored piles.The stay cables are fanned out in double cable planes,and each individual stay cable is composed of parallel-arrangedΦ7 mm high-strength Zn-Al alloy coated steel wires with tensile strength of 1 860 MPa.To address the issues of long span,wide deck and heavy vehicle loads,the wind and earthquake resistent techniques on the bridge were given special concern in the study.Configuration of components,like double-cable-plane stay cables,A-shaped pylons and closed cross-section of box girder was analyzed to enhance the wind-resistant stability of the structure,and wind tunnel test was carried out to optimize the structural details,so as to ensure the safety of bridge under wind loads.The adoption of a full-floating system allows the bridge to have an integrated constraint system and sound static and dynamic performance,so that could be safe in earthquake events.To suite the load bearing characteristics of the wide-deck bridge,studies were carried out to examine the structural details,based on which some local members were strengthened,cross beams were set with pre-camber and suggestions and requirements were put forward for the manufacturing and installation of the wide-deck steel girder.The optimization of details of orthotropic steel deck and the proper steel deck pavement also enable the bridge to perform well under heavy loads.
作者
张燕飞
徐恭义
胡辉跃
ZHANG Yan-fei;XU Gong-yi;HU Hui-yue(China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430050,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2020年第S01期1-7,共7页
Bridge Construction
基金
湖北省交通运输厅科技项目(2017-538-2-1)。
关键词
斜拉桥
全飘浮体系
综合约束体系
混合梁
A形混凝土塔
哑铃形承台
设计关键技术
cable-stayed bridge
full-floating system
integrated constraint system
hybrid girder
A-shaped concrete pylon
dumbbell-shaped pile cap
key design technique
