不同风攻角下分离式双箱梁涡振气动力演化和局域相关性研究  

Study on the evolution and local correlation of the aerodynamic force for the separated twin-box girder during vortex-induced vibration at different wind attack angles

作　　者：李玲瑶[1,2] 张敬怡 贺诗昌 何旭辉 徐汉勇[4] LI Lingyao;ZHANG Jingyi;HE Shichang;HE Xuhui;XU Hanyong(School of Civil Engineering,Central South University,Changsha 410075,China;National Engineering Research Center for High-Speed Railway Construction,Changsha 410075,China;Foshan Shunde Lecong Guipu Real Estate Development Co.Ltd.,Foshan 528315,China;School of Civil Engineering,Changsha University,Changsha 410022,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]高速铁路建造技术国家工程研究中心,湖南长沙410075 [3]佛山市顺德区乐从桂圃房地产开发有限公司,广东佛山528315 [4]长沙学院土木工程学院,湖南长沙410022

出　　处：《中南大学学报（自然科学版）》2023年第1期124-136,共13页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51508574,51925808);湖南省自然科学基金资助项目(2021JJ30826);长沙市科技计划项目(kq2014132);中南大学创新驱动计划项目(2020CX009)。

摘　　要：通过弹簧悬挂节段模型同步测振测压风洞试验模拟结构涡激振动,以1座大跨度斜拉桥的分离式双箱梁为研究对象,测定均匀流场中不同风攻角下的涡振响应及表面风压。基于局部特征区域气动力与断面总体气动力的局域相关性概念,分析竖弯涡振时上游断面迎风侧下斜腹板、下游断面迎风侧斜腹板及顶板这3个关键局部特征区域的气动力演化特性及其与整体总气动力的同步演化关系。研究结果表明:当改变来流攻角时,在分离式双箱梁涡振过程中,不仅会使浸没在流场中的绕流状态、旋涡作用位置发生改变,还会使局部气动力与整体气动力的相关性发生改变。虽然断面不同区域的局部气动力与总体气动力的振动卓越频率相同,但其高阶谐波分量对应频率参与涡振作用的比例却随着风攻角变化而发生变化。另外,分离式双箱梁下游断面迎风侧斜腹板区域与整体断面的涡振特性有着较强的同步演化关系,在实际工程中需重点关注。Synchronal displacement and pressure measurement tests were performed on a spring suspension segment model in wind tunnel. A typical separated twin-box girder of a long-span cable-stayed bridge was used as the research object, and the vortex-induced vibration(VIV) response and surface wind pressure were measured at different wind attack angles in uniform flow. Based on the concept of the local correlation between the local aerodynamic force and the sectional total aerodynamic force, the evolutionary characteristics of the aerodynamic force during the vertical VIV process in three key local characteristic regions, including lower windward side inclined web of the upstream section, the windward side inclined web of the downstream section and top plate, and the synchronous evolution relationship between local and the overall aerodynamic force were analyzed. The results show that under different inflow incidence angles during the VIV process, not only the flow around the submerged section and the effect positions of vortices, but also the local correlations between the local aerodynamic forces and the overall aerodynamic forces are different. The dominant frequencies of the local aerodynamic forces in different regions of the section during the VIV process are the same as that of the total aerodynamic forces, but the proportion of frequencies corresponding to higher harmonics involved in the VIV changes with the wind attack angles. In addition, the VIV characteristics in the region of the windward side inclined web of the downstream section are strongly correlated with those of the whole section, which has to be paid close attention to in engineering practice.

关 键 词：分离式双箱梁 涡激振动 同步测振测压 局部气动力 演化特性 局域相关性 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]