三铰钢拱桥吊杆体系加固方案研究  

Study of Suspenders Rehabilitation Solutions for a Three-Hinged Steel Arch Bridge

作　　者：方艳红 FANG Yan-hong(Wuhan Bridge Special Technology Co.,Ltd.,China Railway Major Bridge Engineering Group,Wuhan 430205,China;State Key Laboratory for Health and Safety of Bridge Structures,Wuhan 430034,China)

机构地区：[1]中铁大桥局武汉桥梁特种技术有限公司,湖北武汉430205 [2]桥梁结构健康与安全国家重点实验室,湖北武汉430034

出　　处：《世界桥梁》2023年第S01期175-182,共8页World Bridges

摘　　要：宁波市灵桥为跨长97.537 m的单跨中承式三铰钢拱桥,为文物保护建筑,吊杆已使用了70多年,且吊杆上弹坑及补焊缺陷较严重。鉴于该桥加固需保留原有历史印记,针对吊杆病害检测情况及材料试验结果,分析灵桥吊杆体系加固前、其余构件加固后的受力状态,提出吊杆维修加固方案,并建立数值模型验证加固方案的可行性与有效性。结果表明:温度和车辆荷载均会使吊杆产生较大的次内力,对端部短吊杆的影响高于其余吊杆,制定加固方案时应着重考虑降低刚性吊杆、端横梁由温度和车辆荷载作用引起的附加应力;吊杆体系加固方案为直接更换吊杆破损角钢及腹板,部分完好板件留用形成组合吊杆,更换端部短吊杆并更改其截面及长度,仍采用铆钉连接;加固后,由温度和车辆荷载引起的吊杆及端横梁附加应力得以有效降低,较加固前受力更加合理,结构安全可靠性更高。The Ling Bridge in Ningbo is a single span,half through,three-hinged steel arch bridge spanning 97.537 m.The bridge has been a local cultural heritage,and the bullet pits in the suspenders reveal its eventful long service life.Although the bridge had experienced multiple rehabilitations in the past eight decades,the repair welding defects of suspenders were still severe.On a like-for-like basis,the rehabilitation solution for the suspenders was presented,which took into account the findings of inspections and material tests as well as the loading conditions of the suspenders after the retrofit of other components and before the rehabilitation of the suspenders.Numerical simulation was conducted to verify the feasibility and efficiency of the rehabilitation solution.As per the study,thermal effects and vehicle braking action can induce great secondary internal forces in the suspenders,the short suspenders at the two ends of the arch were more vulnerable than other suspenders,therefore efforts should be made to reduce the additional stresses induced by the thermal effect and vehicle braking action on the rigid suspenders and arch crossbeams.During rehabilitation,the broken angle sections and webs of the suspenders were directly replaced by new ones,the intact plates were kept in place to form composite suspenders with the new members;the short suspenders at the two ends of the arch were replaced,which were still rivet-connected,but the cross-section and lengths of suspenders were modified.After rehabilitation,the additional stresses in the suspenders and arch crossbeams that were induced by thermal effect and vehicle braking action were effectively released and reduced,the loading conditions of the suspenders are more rational,and the suspenders have got larger safety margin.

关 键 词：三铰钢拱桥 吊杆体系 病害检测 材料试验 加固方案 有限元法 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] U443.38[交通运输工程—道路与铁道工程] U445.71