香溪河大桥倾斜单塔斜拉桥施工技术研究  

Research on Construction Technology of Inclined Single Tower Cable-stayed Bridge of Xiangxi River Bridge

作　　者：佟志峰 张传涛 熊雷 TONG Zhifeng;ZHANG Chuantao;XIONG Lei(CCCC Fourth Highway Engineering Co.,Ltd.,Beijing 100022,China;School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan,Hubei 430070,China)

机构地区：[1]中交第四公路工程局有限公司,北京100022 [2]武汉理工大学土木工程与建筑学院,湖北武汉430070

出　　处：《公路工程》2023年第4期9-15,97,共8页Highway Engineering

基　　金：国家自然科学基金资助项目(51708436,51908437)。

摘　　要：兴山县峡口香溪河大桥为(90+238)m非对称异形独斜塔单索面斜拉桥,桥塔采用塔身整体在空间上呈扭曲变化的“琵琶”形斜塔。大桥地处高山峡谷、地基土层软弱的恶劣环境中,这对斜拉桥施工的安全风险控制提出了更高的要求。针对曲线变截面塔身施工的传统模板控制及安装等难点,结合现场施工的BIM仿真模型采用可调圆弧模板技术,解决了传统模板调节弧度困难的问题,降低了施工难度和风险;针对无索区段斜塔施工安全风险高的难点,采用桥塔背向支撑、斜拉索张拉和主梁配重的多重控制施工方法,不仅显著增大了结构施工应力安全余量,而且有效减小了软弱地基因受力过大而发生破坏的风险;针对桥塔背向支撑落地搭设施工面临的支撑大直径钢管穿过主梁梁体的问题,采用小直径钢棒穿梁技术,解决了大直径钢管穿过主梁导致主梁承载力削弱、应力集中及预应力钢束位置冲突的问题。Xiangxi River Bridge in Xiakou,Xingshan County is a(90+238)m cable-stayed bridge with asymmetric special-shaped pylon and single cable plane,the tower adopts the pipa-shaped inclined tower whose whole body is twisted in space.The bridge is located in high mountains and canyons,and the foundation soil is weak,which puts forward higher requirements for the safety risk control during the construction of cable-stayed bridge.for the difficulties of traditional formwork control and installation in the construction of curved variable-section tower,combined with BIM simulation model in site construction,the adjustable arc formwork technology is adopted to solve the problem of traditional formwork regulating radian,the construction difficulty and risk are reduced;for the difficulty of high safety risk in the construction of inclined pylon in non-cable section,the multiple control construction methods of tower bracket,cable tension and main beam weight balance are adopted,which not only significantly increase the safety margin of stress in the construction of the structure,but also increase the safety margin of the structure,and effectively reduce the risk of weak ground gene damage caused by excessive force;for the problem of supporting large-diameter steel pipe through the main beam body in the construction of bridge tower back-supporting landing lap,the small-diameter steel bar through the beam body is adopted,the problems of bearing capacity weakening,stress concentration and position conflict of prestressed steel beam caused by large diameter steel tube passing through the main beam are solved.

关 键 词：斜拉桥 异形斜塔 BIM 可调圆弧模板 桥塔支撑 配重 小直径钢棒穿梁 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]