摘要
川南城际铁路临港公铁两用长江大桥主桥为主跨522 m双塔双索面钢箱梁斜拉桥,桥塔为钻石形钢筋混凝土结构,塔高250.8 m,设中、下横梁各1道及上横梁2道。桥塔采用液压爬模施工,其中下塔柱与下横梁采用同步施工;中、上塔柱与中、上横梁及连接板采用异步施工。在中、上塔柱施工时,中、上塔柱间设置6道主动横撑,解决了塔柱、横梁异步施工时内倾塔柱因自由长度过长导致其根部受力较大的问题,避免了开裂;中横梁采用附壁支架施工,设计简洁且耗材少,整体安装快速便捷,承载性能好;连接板采用无水平推力弧形拱架施工,解决了跨度大、承载力要求高的问题;风洞与上横梁采用落地式组合支架施工,既解决了狭小空间内部支撑构件的安拆问题,又满足承载力强、稳定性高、风险小的要求。
The main bridge of Lingang Changjiang River Rail-cum-Road Bridge that carries a section of the Mianyang-Luzhou High-speed Railway is a steel box girder cable-stayed bridge with a main span of 522 m.The stay cables are fanned out in double cable planes.The bridge features its two diamond-shaped reinforced concrete pylons,each rising 250.8 m and having an intermediate crossbeam,a lower crossbeam and two upper crossbeams.The pylons were constructed by using hydraulic climbing formwork,the construction of the lower pylon columns was carried out in parallel with the construction of the lower crossbeams,while the construction of the intermediate and upper pylon columns were not performed simultaneously with the construction of the intermediate and upper crossbeams and connecting plates.During the construction of the intermediate and the upper pylon columns,a number of six active lateral struts were installed between the intermediate and upper pylon columns,to counteract the excessive loads at the roots of the inwardly-inclined pylon columns due to the excessive free lengths of the inwardly-inclined pylon columns during the unsynchronized construction of the pylon columns and crossbeams,as well as to avoid cracking.The intermediate crossbeam was constructed using buttressed scaffolds,which revealed a great reconciliation between minimalist design,smaller amount of materials consumed,being available for rapid installation and ensured load bearing capacity.Due to that the connecting plates were required to have good load bearing capacity and span long distance,the arch centering without horizontal thrust was employed for the installation of the connecting plates.The wind cavities and upper crossbeams were installed on the floor-standing composite scaffolds,to avoid the installation and demolition of inner supporting components in limited space and meet the critical load bearing,stability and safety requirements.
作者
陈正
于志兵
徐代宏
韩冰
陈博
CHEN Zheng;YU Zhi-bing;XU Dai-hong;HAN Bing;CHEN Bo(Sichuan Road and Bridge Construction Group Co.,Ltd.,Chengdu 610041,China;South Sichuan Intercity Railway Co.,Ltd.,Zigong 643000,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2023年第1期123-129,共7页
Bridge Construction
基金
四川省交通科技项目(2021-ZL-12)。
关键词
公路铁路两用桥
斜拉桥
钢筋混凝土桥塔
塔柱
横梁
连接板
异步施工
施工技术
rail-cum-road bridge
cable-stayed bridge
reinforced concrete pylon
pylon column
crossbeam
connecting plate
unsynchronized construction
construction technique
