不同交通流下车辆对桥梁涡振稳定性影响的试验研究

发布时间：2018-01-15 22:13

本文关键词：不同交通流下车辆对桥梁涡振稳定性影响的试验研究　出处：《安全与环境学报》2014年05期 　论文类型：期刊论文

【摘要】：涡激振动是桥梁风致振动中最常见的现象,通常在较低的风速下发生,且对结构气动外形的变化很敏感,车辆行驶在桥梁上势必会改变桥梁断面的外形,因此,研究不同交通流下车辆对桥梁涡激振动的影响非常必要。为了考虑实际运营中车辆对桥梁涡振的影响,基于自由悬挂节段模型试验系统,分别对无车、自由车流和繁忙车流3种交通流状态下车辆对桥梁涡振振动的影响进行了风洞试验。测试了涡振响应和涡振频率,分析了车辆对桥梁涡振响应的影响及机理。结果表明,由于车流显著改变了主梁的气动外形,并且增加了系统质量,不同交通流下车辆对桥梁涡激振动起到了抑制作用。偏于安全考虑,实际桥梁的涡激振动试验可以不用考虑车辆的影响。
[Abstract]:Vortex-induced vibration is the most common phenomenon in wind-induced vibration of bridges. It usually occurs at lower wind speed and is sensitive to the changes of aerodynamic shapes of structures. Vehicle driving on the bridge will inevitably change the shape of the bridge section. It is necessary to study the effect of vehicles on the vortex-induced vibration of bridges under different traffic flows. In order to consider the effect of vehicles on the vortex-induced vibration of bridges in practical operation, based on the free-suspension segment model test system, no vehicle is considered. Wind tunnel tests were carried out on the effects of vehicle on the vortex vibration of the bridge under the three traffic conditions of free vehicle flow and busy vehicle flow. The response and frequency of vortex vibration were measured. The effect and mechanism of vehicle on the vortex vibration response of the bridge are analyzed. The results show that the aerodynamic shape of the main beam is changed obviously and the system quality is increased because of the vehicle flow. The vehicle under different traffic flow can restrain the vortex-induced vibration of the bridge. Considering the safety, the effect of the vehicle can be neglected in the actual test of the vortex-induced vibration of the bridge.
【作者单位】：长沙理工大学桥梁工程安全控制技术与装备湖南省工程技术研究中心;美国路易斯安那州立大学土木与环境工程学院;
【基金】：国家自然科学基金项目(51278069,51208067) 交通部西部交通科技项目重大科技专项(2011 318 824 140) 长沙理工大学桥梁工程安全控制技术与装备湖南省工程技术研究中心项目(12KC02) 铁四院科研项目
【分类号】：U441.3
【正文快照】： 0引言当气流流经非流线型断面时会在断面尾部形成周期性交替脱落的涡脱,当涡脱频率与结构某一自振频率接近时会产生涡激共振现象。虽然涡激振动是一种限幅振动,不会使结构发生气动失稳现象,但其产生的风速区间低,长时间的振动会使结构发生疲劳,并且严重影响行车的舒适安全性。

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