某大桥钢桁拱架预压试验分析

Analysis of Pre-compression Test of a Bridge Steel Truss Arch

以某拱桥主拱圈现浇施工为研究背景,参照其他同类桥梁主拱圈现浇施工经验和方法,结合现场施工条件,设计了某大桥钢桁拱架预压试验,提出了合理的预压方案,通过贝雷拱架预压,有效消除了其非弹性变形。同时,通过建立钢拱架有限元模型,对拱架预压进行全过程模拟,经理论计算与实测结果对比表明:理论计算值与预压实测值的偏差较小,实际测量值略小于理论计算值,表明拱架整体刚度大于理论计算值,其承载能力比设计更为理想。

Taking the cast-in-place construction of the main arch ring of an arch bridge as the research background,referring to the experience and methods of cast-in-place construction of the main arch rings of other similar bridges,combined with the on-site construction conditions,a preloading test of a bridge steel raft arch was designed and a reasonable preload was proposed.The program,through the pre-pressing of the Bailey arch,effectively eliminates its non-elastic deformation.At the same time,through the establishment of the steel arch finite element model,the whole process of the arch preloading is simulated.The comparison between the theoretical calculation and the measured results shows that the deviation between the theoretical calculation value and the pre-compaction measurement value is small,and the actual measurement value is slightly smaller than the theoretical calculation.The value indicates that the overall stiffness of the arch is greater than the theoretical calculation,and its carrying capacity is better than the design.