考虑四肢桥塔遮风效应的常泰长江大桥风-车-桥耦合振动研究  

Study of Wind-Vehicle-Bridge Coupling Vibration of Changtai Changjiang River Bridge Considering Wind Shielding Effect of Four-Column Pylon

作　　者：韩旭 向活跃[1] 李镇[2] 苑仁安[3] 李永乐[1] HAN Xu;XIANG Huoyue;LI Zhen;YUAN Renan;LI Yongle(Department of Bridge Engineering,Southwest Jiaotong University,Chengdu 610031,China;Jiangsu Provincial Transportation Engineering Construction Bureau,Nanjing 210004,China;China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430056,China)

机构地区：[1]西南交通大学桥梁工程系,四川成都610031 [2]江苏省交通工程建设局,江苏南京210004 [3]中铁大桥勘测设计院集团有限公司,湖北武汉430056

出　　处：《桥梁建设》2023年第4期8-15,共8页Bridge Construction

基　　金：国家自然科学基金项目(51978589);中央高校基本科研业务费项目(2682021CG014)。

摘　　要：常泰长江大桥主航道桥为跨径布置(142+490+1176+490+142)m的双塔双索面双层公铁两用斜拉桥,采用空间钻石型桥塔。为保证该桥因四肢桥塔遮风效应引起风速突变时的行车安全性和舒适性,通过风洞试验测得车-桥组合状态下列车及桥梁的气动力系数和四肢桥塔区桥面风环境,分析线路位置的影响,在此基础上采用ANSYS软件建立该桥有限元模型,采用Matlab编制风-车-桥耦合振动分析程序,研究桥塔遮风效应对风-车-桥耦合振动性能的影响,对比分析风速和车速对列车动力响应的影响。结果表明:四肢桥塔遮风效应会引起连续2次风速突变,风速突变率达86%;四肢桥塔遮风效应使列车车体竖向加速度最大值由0.22 m/s^(2)增加到0.76 m/s^(2),横向加速度最大值由0.20 m/s^(2)增加到0.62 m/s^(2);风速越高,桥塔引起的列车动力响应突变程度越明显;不同车速下桥塔遮风效应对列车动力响应的影响较为接近。The main navigational channel bridge of Changtai Changjiang River Bridge is a cable-stayed bridge with a main span of 1176 m,two side span of 490 m and two end spans of 142 m.The bridge is a double-decker serving multiple purposes.The stay cables are fanned out in double cable planes.The two pylons are spatial diamond-shaped pylons.The wind shielding effect of the four-column pylon is likely to induce accidental change of wind speeds and threaten vehicle travelling safety and comfort.Wind tunnel tests were carried out to obtain the aerodynamic coefficients of the vehicles and the bridge under vehicle-bridge coupling vibrations,investigate the wind environments over the deck in the four-column pylon zones and analyze the influence of different route alignments.Upon which,a finite element model was developed in ANSYS and a wind-vehicle-bridge coupling vibration analysis program was compiled in Matlab to study the impact of wind shielding effect on the wind-vehicle-bridge coupling vibrations and compare the effects of wind and vehicle speeds on the dynamic responses of vehicles.It is shown that the wind shielding effect of four-column pylon can cause two times of accidental wind speed changes,with a change rate of 86%.Under the action of wind shielding effect,the maximum vertical and transverse accelerations of the vehicle body are increased from 0.22 m/s^(2) to 0.76 m/s^(2),and 0.20 m/s^(2) to 0.62 m/s^(2),respectively.The higher the wind speed,the more significant the accidental change of pylon-induced vehicle responses.Under different vehicle speeds,the impacts of wind shielding effect of pylon on the vehicle responses are observed in approximate agreement.

关 键 词：斜拉桥 四肢桥塔 遮风效应 行车安全 风环境 风洞试验 风-车-桥耦合振动分析 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U441.3[交通运输工程—道路与铁道工程]