摘要
新建成渝中线简阳沱江特大桥主桥为(72+320+72)m中承式无推力组合拱桥,主拱为钢管混凝土拱,边拱为钢-混组合箱拱,边拱端部拱梁一体,主梁作为系杆,成都侧拱座设纵向活动支座。根据该桥结构特点、水文和地质条件、无砟轨道线形精度要求,边拱采用支架法施工,在主拱合龙前和二期恒载施工前分2次浇筑边拱压重混凝土,以平衡拱脚混凝土应力和边支座的反力;主拱分为三大段,两端73 m拱段采用原位支架拼装方案施工,跨中174 m拱段采用“低位拼装、整体垂直提升”方案施工;主梁采用支架法施工,在主梁跨中合龙段设置临时拉索,主动张拉合龙,同时可通过临时拉索的多次主动张拉将成都侧拱座滑移量控制在20 mm内;在成都侧拱座往中跨侧滑移的方向上设置临时约束,利用支座垫石作为限位挡块,限制主拱合龙前拱座往中跨侧的滑移。
The main bridge of Jianyang Tuojiang River Bridge of Second Chengdu-Chongqing High-speed Railway is a half-through arch bridge with three spans of 72,320 and 72 m.The thrustless arch consists of a main concrete-filled steel tubular(CFST)arch and two side steel-concrete composite box arches,the tips of the side arches merge with the deck system,creating a tied-arch system.Bearings allowing longitudinal movement are installed at the Chengdu-side skewback.Counterweight concrete in the side arches was cast both before the closure of the main arch and ahead of the application of the secondary dead loads,to balance the stresses in the concrete of arch springings and the reaction forces of the bearings at piers.The main arch was divided into three sections to facilitate the construction,the two 73 m-long sections(counting from the skewbacks)were assembled in situ on scaffolds,the 174 m-long center section was assembled into a whole at a lower elevation and then vertically lifted into place.The deck system was erected on scaffolds,temporary cables were installed at the key segment of the deck to achieve positive closure of the deck via tensioning the cables.Multiple positive tensioning of the temporary cables was also beneficial to the control of the slip of the Chengdu-side skewback(the slip was controlled within 20 mm).A temporary restraint was installed to limit the slip of the Chengdu-side skewback towards the main span,and pad stone of the bearings was used as a stopper to limit the slip of the skewback towards the main span before the closure of the main arch.
作者
李传富
李永乐
马天亮
张大兵
LI Chuanfu;LI Yongle;MA Tianliang;ZHANG Dabing(Southwest Jiaotong University,Chengdu 610031,China;Chenggui Railway Co.,Ltd.,Chengdu 614000,China;China Railway Major Bridge Engineering Group Co.,Ltd.,Wuhan 430050,China;China Railway Bridge Science Research Institute,Ltd.,Wuhan 430034,China)
出处
《桥梁建设》
北大核心
2025年第2期146-152,共7页
Bridge Construction
关键词
高速铁路桥
无推力组合拱桥
钢管混凝土拱
钢-混组合箱拱
边拱压重
整体提升
临时约束
施工方案
high-speed railway bridge
thrustless composite arch bridge
concrete-filled steel tubular arch
steel-concrete composite box arch
side-arch counterweight
integral lift
temporary restraint
construction scheme
