大跨度连续钢桁架拱桥半悬臂拼装临时墩合理标高计算

Elevation Calculation for Temporary Pier of Large-span Continuous Steel Truss Arch Bridge Assembled by Semi-cantilevering

当大跨度连续钢桁架拱桥采用支架法施工时,其临时支墩标高的合理设定对大桥的拼装线形和安全顺利拼装具有重要影响。结合钢桁梁桥的制造线形和架设过程中的钢梁线形变化,较系统地研究了临时墩的标高计算,推导了实用的计算公式。然后将该方法应用于某大跨度钢桁梁柔性拱组合结构桥梁,现场拼装和拆除结果表明:考虑预留50 mm的设置方法,能更方便临时墩拆除,为类似桥梁施工计算提供借鉴。

The temporary pier elevation has significant influence on construction line and safety of large-span steel truss arch bridges assembled by semi-cantilevering. In this paper, based on the alignment changes of steel truss during manufacturing and assembling, calculation for the elevation of temporary piers has been studied systematically, and the practical computational formula has been deduced. Then, following its application on one large-span steel truss arch bridge, the obtained results indicate that, preserved 50 mm can provide much more convenience for removal of the temporary pier from the computation, which has been proved to be reasonable and reliable, and can provide reference for similar bridge works.