根据随机交通状况修正横截面尺寸的大跨桥梁的风致性能

现有的交通状况对细长大跨桥梁(SLB)面板主要影响有两类:1)桥梁横截面尺寸发生改变,这可能会反过来改变颤振导数及作用在桥梁上的风致气动弹性荷载;2)作用于桥梁上的附加动力荷载,包括来自于车辆的动力相互作用。与外部动力荷载——车辆相比,通过改变桥梁横截面尺寸来研究其影响是很少见的。在桥面板上分布车辆模型,在风洞实验室模拟随机交通流对按比例制作的桥梁截面模型进行试验。在风洞试验中通过改变桥梁的横截面尺寸来获得不同的颤振导数,目前的研究是从数值上评估其对大跨桥梁的风致性能,如气动弹性性能、风致响应和潜在疲劳累积性能的影响。

Wind-Induced Performance of Long-Span Bridge with Modified Cross-Section Profiles by Stochastic Traffic

The presence of traffic on a slender long-span bridge (SLB) deck has two types of primary impacts: 1) modification of the bridge cross-section profiles, which may influence the flutter derivatives and in turn, wind-induced aeroelastic loads acting on the bridge and; 2) additional dynamic loads acting on the bridge including dynamic interactions from the vehicles. As compared to the investigations on the impact of traffic as external dynamic loads, those on the impact from the modification of bridge cross-section profiles are rather rare. A scaled bridge section model with vehicle models distributed on the bridge deck has been tested in the wind tunnel laboratory following the simulated stochastic traffic flow. With the flutter derivatives obtained from the wind tunnel experiments of various modified bridge cross-section profiles by traffic, the present study is to numerically evaluate the impact on the wind-induced performance of the long-span bridge, such as the aeroelastic performance, buffeting response and potential fatigue accumulation.