梁拱组合桥施工阶段主梁下挠病害修复  

Main Girder Deflection Correction for a Combined Continuous Girder and Arch Bridge at Construction Stage

作　　者：郑重 顾颖 田小秋 曹江鹏 张梧瑜 ZHENG Zhong;GU Ying;TIAN Xiaoqiu;CAO Jiangpeng;ZHANG Wuyu(CCCC First Highway Consultants Co.,Ltd.,Xi′an 710068,China;School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]中交第一公路勘察设计研究院有限公司,陕西西安710068 [2]西南科技大学土木工程与建筑学院,四川绵阳621010

出　　处：《世界桥梁》2025年第1期125-131,共7页World Bridges

基　　金：四川省科技计划资助项目(2022ZYDF083);陕西省交通运输厅交通科研项目(22-53K)。

摘　　要：某梁拱组合桥采用“先梁后拱”方式建造,施工阶段未张拉吊杆力就拆除梁下支架,导致主梁严重下挠,同时引发梁体开裂、拱梁脱空等病害。针对该桥病害,制定“先梁体顶升复位、后缺陷处治”修复方案。因主梁下挠前线形数据缺失,采用数值模拟结合现场顶升试验,提出顶升高度、顶升力2个控制指标指导主梁顶升复位。顶升高度采用计算的下挠值;顶升力采用“主梁一次落架支反力”。现场共进行20次顶升,顶升过程中顶升高度测试值与计算值的偏差随顶升力的增大而增大,顶升完成时两者偏差达20%,主要因为顶升使梁体裂缝逐渐闭合,刚度逐渐恢复;最终顶升力测试值为19260 kN,与计算值偏差仅2.3%,说明以“主梁一次落架支反力”作为顶升控制目标更符合实际。成桥荷载试验结果显示,修复后的桥梁承载能力满足设计要求,服役状态正常。For the case bridge of a combined continuous girder and arch system,the continuous girder was constructed ahead of the arch.The scaffolds utilized for the installation of the girders were dismantled before the tensioning of suspenders of the arch,as a result,the girders severely deflected,which consequently induced cracks in the girder body and caused the disengagement of the arch and the girders.To address the situation,a proposed remedial plan was to jack up and recenter the girders first,and then treat the defects.Due to the loss of the before-deflection data of the girders,numerical simulation and on-site jacking tests were conducted,and two control indexes of jacking height and jacking force were determined,the jacking heights drew the values of the deflection,and the jacking forces took the reaction forces at the supports.The girders were jacked for 20 times.The deviation between the measured and calculated jacking heights rose as the jacking forces increased,reaching 20%after the completion of jacking,which was attributed to restoration of the girder stiffness due to the closing of the cracks.The measured jacking force was finally at 19260 kN,revealing a 2.3%deviation to the calculated force,indicating it is reasonable to take the reaction forces at the supports as the jacking control targets.The load tests after completion of the bridge demonstrated that the load bearing capacity of the bridge could meet the design requirements after restoration,and the bridge would be in normal service condition.

关 键 词：梁拱组合桥 施工阶段 主梁下挠 病害修复 顶升复位 顶升力 顶升高度 

分 类 号：U443.35[建筑科学—桥梁与隧道工程] U445.71[交通运输工程—道路与铁道工程]