列车通过大跨度桥梁桥塔区域过程中的风-车-桥耦合动力分析

大跨度桥梁位于强横风环境时,桥塔的遮挡作用会使列车进出桥塔区域时车体受到的风力发生变化,这种风荷载的突变效应会对车辆的动力响应造成影响,此外车辆动力响应的改变还会影响桥梁的动力响应.本文以瓯江大跨公铁两用悬索桥为工程背景,以快速谱分析模拟风场,对桥梁子系统施加抖振风力,对桥梁子系统施加稳态风力,考虑桥塔宽度与车辆长度的关系,建立风-车-桥耦合系统运动平衡方程,以全过程迭代法求解该方程,分析计算了不同车速与风速下桥塔遮风效应对车辆桥梁动力响应的影响.结果表明风速和桥塔宽度越大,车辆的动力响应越大,而桥梁动力响应受桥塔遮风效应影响很小.

Analysis on wind-vehicle-bridge dynamic interaction when trian pass through the tower region of long-span bridge

When the long-span bridge is in the strong wind environment, the shielding effects of the bridge tower will change the body-force of the train. This mutation effect of the wind force will change the dynamic response of train and bridge .In this paper, the Oujiang Long-span suspension is used as the engineering background, the fast spectral analysis is used to simulate wind field. In order to establish the motion equation of the wind-vehicle-bridge coupling system, the buffeting wind force on bridge subsystem, steady wind force on the train subsystem and relationship between the width of tower and length of the train are considered and an inter-system history integral procedure is used to solve this equation. The shielding effects of tower under different wind speed and vehicle speed are listed and the results show that the dynamic response of the train will increase with the increase of the wind speed and the length of the tower while the dynamic response of the bridge is very small under the shielding effects of the bridge tower.