润扬悬索桥钢箱梁受力分析及实验研究

FE analysis and experimental study on local stress of steel box girder of runyang suspension bridge

为了研究大跨度悬索桥扁平钢箱梁的工作行为与受力性能,以主跨1490m的润扬悬索桥为研究对象,基于大型有限元分析软件ANSYS建立了该桥的三维有限元整体计算模型,并对其进行了各种工况下的非线性静力分析．在此基础上运用子模型方法,基于局部精细模型计算了钢箱梁的各关键部位的应力．理论和试验结果都表明,该桥钢箱梁各关键部位在车载作用下的应力水平都比较低,但其顶板和顶板U形肋出现的应力疲劳值得重视．

Runyang Suspension Bridge with a main span of 1490m is taken as an example to investigate the mechanical characteristics of the steel box girder of long-span suspension bridges. After a 3-dimensional FE model for the whole bridge and a spatial submodel of the steel box girder were established in detail with finite element analysis software ANSYS, nonlinear FE analyses under various vehicle loads were carried out and the key section stresses of the steel box girder were then calculated with the submodel method. Results show that the stress level of the steel box girder under vehicle loads is low, but the fatigue stresses of the upper board and the ＂U＂ girder under the upper board must be paid special attention.