大跨度拱桥主拱肋支架拆除工序优化研究

Research on Demolition Procedure Optimization of Main Arch Rib Bracket of the Large-span Arch Bridge

为研究拱桥主拱肋支架的合理拆除顺序,文章以某大跨度中承式钢箱系杆拱桥为研究对象,提出了3种主拱肋支架拆除工序优化方案,通过有限元软件建立全桥有限元模型,分析了不同拆除工序方案下各施工阶段拱座水平推力及位移量、拱肋各关键位置位移量。结果表明,综合不同拆除方案的分析结果,以方案三“张拉临时系杆N1、N4→张拉临时系杆N2、N3→松弛扣锁→吊装拱下主梁→拆除主拱肋段支架”为最优方案,研究结论可为类似桥梁工程提供参考。

In order to study the reasonable demolition sequence of the main arch rib bracket of arch bridge,this paper takes a large-span half-through steel box tied arch bridge as the research object,and puts forward three kinds of optimization schemes for the demolition procedure of the main arch rib bracket.The finite element model of the whole bridge is established by finite element software,and the horizontal thrust and displacement of the arch seat and the displacement of each key position of the arch rib at each construction stage under different demolition procedure schemes are analyzed.The results show that,based on the analysis results of different demolition schemes,the scheme 3 of"tensioning temporary tie rod N1,N4→tensioning temporary tie rod N2,N3→loosening locking→hoisting main beam under arch→demolishing bracket in main arch rib section"is the optimal scheme.The research conclusions can provide reference for similar bridge engineering.