钢拱架水箱预压试验及预拱度设置

Water Tank Preloading Test and Pre-camber Arrangement of Steel Arch Frame

以桂阳县龙江渡大桥为工程背景,参照以往混凝土拱桥钢拱架现浇施工建设的经验与成果,对钢拱支架进行了水箱预压试验方案设计,并提出了合理的预压加载和卸载方式。据此,建立了相应的钢拱架有限元模型,并对其强度、刚度以及稳定性进行了计算和分析,结果表明钢拱架的上述性能指标均满足要求,其成果为预压试验提供了可靠的理论数据。预压试验结果表明,钢拱架挠度的实测值与理论计算值吻合较好,表明钢拱架的变形处在弹性范围内,钢拱架的承载能力能够满足拱肋混凝土的浇筑。同时根据预压成果确定了钢拱架的预拱度,对拱肋底部标高控制具有一定的指导意义。

Based on the engineering background of Longjiangdu Bridge in Guiyang county, referring to the steel arch frame of reinforced concrete arch bridge construction experience and achievements in civil engineering application, experiment scheme of water tank preloading is carried out for steel arch frame, and reasonable loading and unloading method are proposed. According to the scheme, the finite element model of the steel arch frame is established to calculate and analyze the strength, stiffness and stability ofsteel arch frame. The results indicate that all above of performance indices meet the requirement, and the model can provide reliable theoretical data for preloading test. The test indicates that deflection＇s measure values match well with the calculated results, which suggest that deflection of steel arch frame is within the range of elasticity, so the bearing capacity of steel arch frame is adequate for the pouring of arch rib. At the same time according to the results of preloading test, pre-camber arrangement value of steel arch frame is determined, which has an important instruction significance to control the elevation of the arch rib bottom.