既有桥梁对新建斜拉桥主梁气动干扰效应的试验研究  

Experimental Study of Aerodynamic Disturbance Effect of Existing Bridge on Main Girder of Under-Construction Cable-Stayed Bridge

作　　者：王铖铖[1] 丁德豪[1] 朱玉[1] WANG Cheng-cheng;DING De-hao;ZHU Yu(CCCC Second Highway Consultants Co.,Ltd.,Wuhan 430056,China)

机构地区：[1]中交第二公路勘察设计研究院有限公司,湖北武汉430056

出　　处：《桥梁建设》2023年第S01期25-30,共6页Bridge Construction

基　　金：中交集团重大科技研发项目(2021-ZJKJ-08)。

摘　　要：为研究既有桥梁对新建斜拉桥主梁的气动干扰效应,以京珠高速改扩建汉江特大桥为背景,进行节段模型测力风洞试验。按1∶50缩尺比制作主梁节段缩尺模型,研究既有桥梁与新建斜拉桥相对位置关系、桥梁间距及风攻角对新建斜拉桥主梁三分力系数的影响。结果表明:既有桥梁对新建桥梁具有明显的气动干扰效应。既有桥梁在上游时,存在明显的遮挡效应,新建桥梁阻力系数整体显著减小;既有桥梁在下游时,新建桥梁阻力系数在正攻角范围内显著减小。升力系数受既有桥梁影响,绝对值整体减小,正攻角时既有桥梁在下游减小更显著。在正攻角范围内,既有桥梁在上游时新建桥梁升力矩系数增大,在下游时则整体减小;在负攻角范围内反之。桥梁间距对阻力系数气动干扰效应的影响突出,间距越大既有桥梁对新建桥梁阻力系数的气动干扰效应相对越小,对升力系数和升力矩系数气动干扰效应的影响较小。In this paper,the under-construction Hanjiang River Bridge of the reconstruction and expansion project of Beijing-Zhuhai Expressway is used as a case to study the aerodynamic disturbance effect of an existing continuous rigid-frame bridge on the main girder of an under-construction cable-stayed bridge.Wind tunnel tests were carried out with a 1∶50 segmental model of the main girder to study the influence of multiple factors on the three-component coefficients of the under-construction cable-stayed bridge,including the locations of the two bridges,the distance of the two bridges and wind attack angles.The results show that the existing bridge can introduce distinct aerodynamic disturbance effect on the under-construction bridge.An upstream existing bridge exerts obvious shielding effect,which causes overall decrease of dragging coefficient of the under-construction bridge.A downstream existing bridge can cause distinct reduction of the dragging coefficient of the under-construction bridge within the range of positive attack angles.Due to the influence of the existing bridge,the absolute value of lift coefficient is globally reduced,at positive attack angles,the reduction is more obvious when the existing bridge is downstream of the under-construction bridge.At positive attack angles,the pitching moment coefficient of the under-construction bridge is increased under the influence of an upstream existing bridge,while globally reduced under a downstream bridge,and the situation is opposite at negative attack angles.The distance of the existing and under-construction bridges has distinct influence on the aerodynamic disturbance effect of dragging coefficient,the bigger the distance,the weaker the aerodynamic disturbance effect on the dragging coefficient of the under-construction bridge,however,the aerodynamic disturbance effect on the lift coefficient and pitching moment coefficient is minimal.

关 键 词：斜拉桥 三分力系数 气动干扰效应 既有桥梁 相对位置 桥梁间距 风攻角 风洞试验 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U441.2[交通运输工程—道路与铁道工程]