摘要
G3铜陵长江公铁大桥主桥为主跨988 m的斜拉-悬索协作体系桥,3号、4号桥塔采用钢筋混凝土门形结构,塔柱高度分别为228.5 m和222.5 m(含4.5 m高的塔座),设1道下横梁、1道上横梁(均采用预应力混凝土结构),塔顶设高25 m的L形钢结构装饰件。该桥桥塔设置三期塔吊辅助施工,塔柱施工首次采用9 m液压爬模施工技术,工期效益明显;塔柱施工设置4道主动横撑,解决了内倾塔柱施工过程中应力和线形控制问题;桥塔下横梁、上横梁均与塔柱异步施工,避免爬模在横梁位置二次安拆;下横梁采用落地支架法施工,合理设置分层高度有效避免横梁产生裂缝;上横梁采用“钢靴+桁片”式支架法施工,支架刚度大、整体性好、安拆便捷,实现了大跨度开口槽形截面上横梁快速施工;根据现场塔吊布置特点及起重能力,塔顶装饰件采用分节段吊装施工,设计了一种适应各异形节段吊装的吊具,提高了吊装工效并降低了吊装风险。
The main bridge of Tongling Changjiang River Rail-cum-Road Bridge carrying a section of G3 Expressway is a hybrid cable-stayed suspension bridge with a main span of 988 m.The pylons supported on main piers No.3 and No.4 are reinforced concrete portal frame structures,with pylon columns reaching heights of 228.5 m and 222.5 m(including the 4.5 m-deep footings),respectively.Each pylon has a lower crossbeam and an upper crossbeam(both are prestressed concrete structures),and a 25 m-high L-shaped steel adornment.The pylons,constructed with the assistance of tower cranes in three phases,were divided into 9 m-long sections for casting by hydraulic climbing formwork,to improve the construction efficiency.Four temporary lateral bracings were added to ease the stress and geometry control of the inwardly-inclined pylon columns during the construction process.The construction of the upper and lower crossbeams did not synchronize with the pylon columns,saving the installation and demolition of climbing formwork at the locations of the crossbeams.The lower crossbeam was cast on ground-standing scaffolds,with rational casting layer thickness to effectively avoid occurrence of cracks.The upper crossbeam was constructed by the scaffolds formed of steel shoes and trusses,which exhibited sound stiffness and integrity as well as ease of installation and demolition,accelerating the construction of the long,trough-cross-sectional upper crossbeam.A type of lifting device that suits the lifting of irregular components was tailored for the pylon-head adornment,resulting in improved lifting efficiency and minimized lifting risk.
作者
郑冰
梁伟
叶庆旱
姚森
赵吉祥
ZHENG Bing;LIANG Wei;YE Qinghan;YAO Sen;ZHAO Jixiang(China Railway Major Bridge Engineering Group Co.,Ltd.,Wuhan 430050,China;State Key Laboratory of Bridge Intelligent and Green Construction,Wuhan 430034,China)
出处
《桥梁建设》
北大核心
2025年第2期10-17,共8页
Bridge Construction
基金
中国中铁股份有限公司科技研究开发计划项目(2022-重点-02)。
关键词
公路铁路两用桥
斜拉-悬索协作体系桥
钢筋混凝土桥塔
液压爬模
分节段吊装
施工技术
rail-cum-road bridge
hybrid cable-stayed suspension bridge
reinforced concrete pylon
hydraulic climbing formwork
section-by-section lifting
construction technique
