大跨度城市轨道交通斜拉桥主梁气动特性CFD研究

摘要

A long span cable-stayed bridge is regarded as the engineering example in this paper,using commercial analysis software CFDfor the numerical wind tunnel simulation,the aerodynamics parameter of three different sections are obtained,which included aerostaticcoefficients,flutter derivatives, aerostatic coefficients of train-bridge system. The effects of wind attack angle, wind speed areinvestigated,and aerodynamics parameters under the condition of train-existing on deck are discussed. The vortex-induced vibration ofdeck are analysed by the power spectrum of lift coefficient curve. With the comparison of aerodynamics parameters of three sections, thedesign of deck section can be more reasonable. The obtained conclusion has some significance for the long span and high pier rail transitcable-stayed bridge.%以某大跨度斜拉桥为背景,采用大型商用软件CFD进行数值风洞模拟,得到了斜拉桥主梁截面三种形式的气动特性参数,即三分力系数、车桥组合下的三分力系数以及颤振导数,讨论了其随攻角和风速变化的规律及原因,考查了车辆存在对主梁断面气动特性的影响,并迸一步由升力系数功率谱曲线分析了主梁的涡振性能,通过三种主梁截面的气动特性对比研究,可进一步对主梁截面进行优化设计,所得结论对大跨高墩轨道交通斜拉桥的主梁截面形式选取具有一定指导意义.