大跨径空腹式连续梁桥施工监控

Construction Monitoring of Long-span Vierendeel Continuous Beam Bridge

空腹式预应力混凝土连续梁桥提高了跨越能力,减少自重和内力,造型简洁美观,但空腹区梁段受力复杂,悬浇施工线形和应力监控难度大。文中以新建的福州洪山大桥为研究背景,监控并分析其施工各阶段的结构行为。采用MIDAS/Civil有限元软件进行全过程数值动态模拟分析,并通过现场数据采集实时修正数值模型,调整和预测施工阶段的结构变形、立模标高及关键截面应力,至桥梁合拢。经监控调整,合拢精度高,成桥线形和应力与设计误差小,满足规范要求,监控效果好,可为同类桥梁施工提供参考。

The vierendeel prestressed concrete continuous beam bridge has improved the span ability,the dead weight and internal force is re duced,and the shape is simple and beautiful,but the stress of beam section in the vierendeel area is complex,it is difficult to monitor the co nstruction alignment and stress in the process of suspended pouring.This paper takes the newly built Hongshan Bridge in Fuzhou as a resear ch background,its structural behaviors at the various stages of construction are monitored and analyzed.The MIDAS/Civil finite element softw are is used to carry out the numerical dynamic simulation analysis of the whole process,and the numerical model is modified in real time thro ugh the field data acquisition,so that the structural deformation,formwork erection elevation and key section stress in the construction stage a re adjusted and predicted,until the bridge is closed.After monitoring and adjusting,the closure precision is high,the errors of the bridge ali gnment and stress with the design are small,the requirements of the code is met,the monitoring effect is good,a reference can be provided fo r the similar bridge construction.