横向紊流风作用下桁架梁上高速列车抖振力空间相关性试验研究

Wind tunnel tests on the spatial correlation of buffeting forces of high-speed trains on steel truss girder under turbulent cross wind

为分析横风作用下钢桁梁上高速列车受到抖振力的空间相关性,在XNJD-3风洞实验室建立了两种大气紊流场,基于1∶29.7的车桥节段模型,采用同步测压法得到了静止列车上的抖振力分布,尝试从时域、频域两个方面分析攻角、紊流场、列车位置等参数对列车抖振力空间相关性的影响,并对试验现象及影响因素总结,提出了列车抖振力跨向相干函数的拟合公式,证实了列车侧向抖振力的相关性与顺风向脉动风的相关性较接近,升力和力矩的相关性略小于竖向脉动风的相关性,也指出了进一步的研究方向,研究结论对类似桥梁上列车运行的舒适性研究具有指导意义。

In order to investigate the span-wise correlation characteristics of buffeting forces of high-speed train, two kinds of atmospheric turbulence fields were established in XNJD-3 wind tunnel. The scale of the bridge segment and vehicle models was 1 ： 29.7. Based on the simultaneous pressure measurement method, the distribution of buffeting forces of still trains was obtained. Then, the influences of those factors, including wind attack angles, turbulent flow fields and locations of trains, on the spatial correlation of the buffeting forces was analyzed in time domain and frequency domain. Furthermore, relationships between the correlation coefficients of buffeting forces and incident flow features were studied, the mechanism and influence factors were summarized, and the fitting formulas of span-wise coherence function of buffeting forces were proposed. The results show that the span-wise correlation of lateral buffeting forces is close to the correlation of downwind fluctuating wind. The correlation of lift force and torsion moment is slightly smaller than that of the vertical fluctuating wind. Eventually, future research directions are pointed out. The conclusions drawn in this study can be referred by those studies on the comfort of trains running on similar bridges.