摘要
施工中的钢桥塔,特别当桥塔主体工程完成,而主缆尚未架设时,易发生风致振动。为了研究施工状态下,塔吊对钢桥塔风致振动的影响,以某大跨度斜拉桥钢桥塔和塔吊组合体系为实际工程背景,采用风洞试验方法,在均匀流场中测试了裸塔状态下和桥塔与塔吊组合体系下各自的风致振动响应,并将两者的测试结果进行对比分析。研究结果表明:裸塔状态下的钢桥塔气弹模型在0°风向角下会出现较为明显的大幅顺桥向涡激振动现象,随着风速的增长,当风速达到47 m/s后,裸塔状态下的钢桥塔气弹模型会发生大幅的发散性驰振现象。另一方面,随着风向角度的增加,钢桥塔风致振动响应降低较为显著,没有发生较为明显的涡激振动和发散性驰振现象。在所有试验风向角工况下,钢桥塔和塔吊组合体系状态在均匀流场中的风致振动响应相比钢桥塔裸塔状态显著减小,并且未发生明显的涡激振动和驰振现象,这表明塔吊的存在会明显抑制钢桥塔的风致振动响应。今后在考虑施工态下风荷载对钢桥塔施工安全的影响时,不仅应考查裸塔状态钢桥塔的风致振动响应,还应考查钢桥塔和塔吊组合体系下的风致振动响应。本研究结论可为施工态下同类钢桥塔的风致施工安全提供一定的参考。
The steel pylon under construction is prone to wind-induced vibration,especially when the main bridge pylon is completed and the main cable has not yet been erected.In order to study the influence of tower crane on wind-induced vibration of steel bridge pylon under construction,taking the combination system of the tower crane and the steel pylon of a long-span cable-stayed bridge as project background,the windinduced vibration responses of nude pylon and the abovementioned combination system under the condition of uniform flow are tested in the uniform flow field by wind tunnel test,and their test results are compared and analyzed.The research result shows that(1)The large amplitude vortex-induced vibration in longitudinal direction of the aeroelastic model of nude pylon occurs obviously with the wind angle of 0°.As the wind speed increasing,the large amplitude divergent galloping of the aeroelastic model of nude pylon occurs when the wind speed is 47 m/s.(2)On the other hand,as the wind angle increasing,the wind-induced vibration response of steel pylon decreases obviously,and no obvious vortex-induced vibration and divergent galloping occurs.With all the wind angles in test,the wind-induced vibration response of the combination system in the uniform flow field is significantly reduced compared to that of the steel bridge pylon,without obvious occurrence of the vortex-induced vibration and the galloping,indicating that the tower crane could inhibit the wind-induced vibration response of the pylon obviously.In the future,when considering the influence of wind load on the construction safety of steel bridge pylons under construction,not only the wind-induced vibration response in the state of bare pylons,but also the wind-induced vibration response of the combination system of steel bridge pylon and tower crane should be examined.The research result could provide a reference for the wind-induced construction safety of similar type steel pylon under construction.
作者
苏洋
李鹏
胡朋
林伟
SU Yang;LI Peng;HU Peng;LIN Wei(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;CCCC Second Highway Engineering Co.,Ltd.,Xi’an Shaanxi 710065,China;School of Civil Engineering,Changsha University of Science and Technology,Changsha Hunan 410114,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2020年第9期67-72,89,共7页
Journal of Highway and Transportation Research and Development
基金
湖南省自然科学基金项目(2018JJ3538)。
关键词
桥梁工程
涡激振动
风洞试验
桥塔
塔吊
bridge engineering
vortex-induced vibration
wind tunnel test
pylon
tower crane
