双幅连续梁桥钢箱梁涡激振动机理分析  

VIV mechanism analysis of steel box girder of double continuous girder bridge

作　　者：董国朝[1] 许育升 韩艳[1] 李凯 DONG Guochao;XU Yusheng;HAN Yan;LI Kai(Key Laboratory for Safety Control of Bridge Engineering Ministry of Education,Changsha University of Science&Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学桥梁工程安全控制教育部重点实验室,长沙410114

出　　处：《振动与冲击》2022年第9期237-243,共7页Journal of Vibration and Shock

基　　金：国家自然科学优秀青年基金(51822803);国家自然科学基金(51678079,51778073,51978087);国家自然科学基金青年项目(51908074);湖南省杰出青年基金(2018JJ1027);湖南省教育厅科学优秀青年基金(16B011);湖南省研究生科研创新资助项目(CX20200848)。

摘　　要：对某双幅钢箱梁连续梁桥涡激振动进行风洞试验和数值模拟研究。基于二次开发UDF(user defined function)程序嵌入Fluent软件进行二维流固耦合分析,模拟了双幅桥梁断面的涡激振动;通过对比节段模型风洞试验及数值模拟结果,验证了数值模拟方法的可靠性,并从流场的角度直观分析双幅钢箱梁断面涡激振动机理。研究结果表明:上游幅主梁断面下表面的主涡与其背风侧的正压区的周期性变化诱发了上游幅主梁断面的竖向涡激振动;下游幅主梁断面上、下表面的旋涡交替作用于主梁断面并脱落,形成了周期性的作用,导致了下游幅主梁断面的竖向涡激共振;下游幅主梁断面上、下表面的旋涡分别在迎风侧栏杆与上游幅箱梁尾部、下游幅箱梁前端得到增强,导致了下游幅主梁断面的涡激振动的振幅大于上游幅主梁断面。研究结果为双幅桥梁或双钝体断面的涡激振动研究提供参考经验。Here,vortex induced vibration(VIV)of a double-steel box girder continuous girder bridge was studied by using wind tunnel tests and numerical simulation.Based on the secondary developed user defined function(UDF)program embedded in FLUENT for 2 D fluid-structure interaction analysis,VIV of double-box girder bridge section was simulated.By comparing results of bridge segmental model wind tunnel tests and the model numerical simulation results,the reliability of the numerical simulation method was verified,and the VIV mechanism of double-steel box girder section was intuitively analyzed from the perspective of flow field.The results showed that periodic changes of the main vortex on the lower surface of the upstream main beam section and its barotropic zone on the leeward side induce vertical VIV of the upstream main beam section;vortices on upper and lower surfaces of the downstream main beam section alternately act on the main beam section and fall off to form a periodic action,and cause vertical VIV of the downstream main beam section;vortices on upper and lower surfaces of the downstream main beam section are strengthened at windward side railing,upstream box girder tail and front end of downstream box girder,respectively to cause VIV amplitude of the downstream main beam section larger than that of the upstream main beam section;the results provide reference and experience for studying VIV of double-box girder bridges or double-blunt body sections.

关 键 词：双幅箱梁 涡激共振 数值模拟 机理 连续梁桥 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]