摘要
为保障在役斜拉桥更换斜拉索的结构安全与施工质量,提出了基于标高-索力双控的全过程换索监控体系,建立了索力-主梁挠度双参数反馈的闭环校核方法,系统研究了在役斜拉桥(广州江村大桥)的48根斜拉索更换施工的全过程监控技术及结构响应特征,并采用全站仪、无线索力测试仪及应力综合测试系统对主梁变形、桥塔偏位、索力与应力进行了实测。结果表明:1)施工过程中主梁挠度偏差控制在5 mm以内,<20 mm限值;2)主塔最大纵向偏移量为43.8 mm,小于理论计算值45.2 mm;3)索力偏差为-4.51%~6.01%,满足规范索力控制值±10%的要求;4)主梁各对应测点的应力累积变化值范围为-1.06 MPa~0.73 MPa,且斜拉索更换前后主梁应力值基本一致;5)全桥线形偏差在7 mm以内,<20 mm限值。标高-索力双控方法可供类似在役斜拉桥维修改造工程参考。
To ensure the structural safety and construction quality during the replacement of stay cables for in-service cable-stayed bridges,a full-process cable replacement monitoring system based on dual control of elevation and cable force was proposed in this paper,and a closed-loop verification method with dualparameter feedback of cable force and girder deflection was established.A systematic study was conducted on the full-process monitoring techniques and structural response characteristics during the replacement of 48 stay cables of the in-service cable-stayed bridge(Jiangcun bridge in Guangzhou).A combination of total stations,wireless cable force testers,and integrated stress testing systems was employed to conduct on-site measurements of girder deformation,pylon displacement,cable force,and stress.The results indicate that:1)During construction,the deviation of girder deflection was controlled within 5 mm,which is less than the 20 mm limit;2)The maximum longitudinal displacement of the pylon was 43.8 mm,lower than the theoretical calculated value of 45.2 mm;3)The cable force deviation ranged from-4.51%to 6.01%,meeting the specification requirement of±10%;4)The cumulative stress variation at corresponding measuring points on the girder was between-1.06 MPa and 0.73 MPa,and the girder stress remained basically consistent before and after cable replacement;5)The alignment deviation of overall bridge was within 7 mm,below the 20 mm limit.The elevation-cable force dual control method employed in this paper can provide technical support for the maintenance and renovation of similar inservice cable-stayed bridges.
作者
周泉
黎毅
袁正惠
陈飞
ZHOU Quan;LI Yi;YUAN Zhenghui;CHEN Fei(Guangzhou Road Maintenance Center,Guangzhou 510000;Guangdong Baiyun University,Guangzhou 510080;China Merchants Chongqing Communications Technology Research&Design Institute Co.,Ltd.,Chongqing 400067)
出处
《公路交通技术》
2025年第6期127-136,共10页
Technology of Highway and Transport
关键词
斜拉桥
斜拉索更换
标高-索力双控
拉索索力
主梁变形
cable-stayed bridge
stay cable replacement
elevation-cable force dual control
cable force
main girder deformation
