新型大跨连续钢桁组合梁桥施工监控关键技术

Key Construction and Monitoring Technologies of New Long-span Continuous Steel Truss Composite Girder Bridge

大跨度连续钢桁架-混凝土组合梁桥在公路桥梁上应用的实例极少,且有关大跨组合结构桥梁施工监控及相关问题的研究还处在探索阶段。依托某连续桁架组合梁桥工程,采用了新颖的抗拔不抗剪剪力键,并对传统的混凝土桥面板浇筑顺序进行了调整,极大地提高了负弯矩混凝土的抗裂性能。桥梁施工阶段的拆架跨中位移量、跨中混凝土预压应力、桥面板与钢梁滑移量是本桥监测的重点内容,为实现成桥状态设计目标,精确而有效的施工监控至关重要。将监测结果与有限元分析软件理论数据进行对比,分析判断桥梁施工过程中的安全性,确保全桥施工的顺利进行。

The application of long-span continuous steel truss-concrete composite girder bridge is very rare in the highway bridge,and the study on the construction,monitoring and related problems of long-span composite structure bridge is still in the exploratory stage.Based on a continuous truss composite girder bridge project,a new pullout-not-shear-resistant key is adopted,and the traditional pouring sequence of concrete bridge deck is adjusted,which greatly improves the anti-cracking performance of negative moment concrete.In the construction stage of the bridge,the displacements in the disassembly mid-span,the precompression stress of the mid-span concrete,the slip of the bridge deck and the steel beam are the key contents of the bridge monitoring.In order to achieve the design goal of the state of bridge,it is very important to accurately and effectively monitor the construction.The monitoring results are compared with the theoretical data of the finite element analysis software to analyze and judge the safety of construction process,and ensure the smooth construction of the whole bridge.