摘要
为解决桥梁接触网设计风荷载取值问题,提出桥梁接触网设计风速及风荷载的修正方法。通过桥梁节段及风屏障缩尺模型风洞试验,确定某桁架桥梁接触网的桥梁断面及风屏障的风速修正系数;通过刚性节段模型测力风洞试验,确定了单承力索、双承力索、接触线、单线单导和双线单导等不同布置形式接触网的体型系数;根据试验测试的修正系数,计算按本文修正方法计算的设计风荷载取值与规范值对比。研究结果表明:考虑桁架梁断面及桥上风屏障后,桥面接触线位置处风速修正系数取1.13,承力索位置处风速修正系数取1.14,可知桥梁断面及风屏障会提高接触网设计风速;不同布置形式接触网体型系数按不同风速工况的包络值,接触线取1.4,单承力索取1.5,双承力索取1.75,明显大于现行规范的取值1.2。根据试验测试的修正系数计算的接触线、单承力索和双承力索设计风荷载结果是现行规范的1.46倍、1.6倍和1.86倍,表明桥梁接触网设计风荷载取值会比普通接触网显著增加。研究成果可为桥梁接触网设计阶段风荷载取值提供参考,为我国电气化铁路接触网设计规范的条文修订提供支撑。
In order to solve the problem of wind load value in bridge catenary design,a method of wind speed and wind load correction in bridge catenary design was proposed.Through the wind tunnel test of the bridge segment and wind barrier scale model,the wind speed correction coefficient of a truss-bridge section with wind barrier was determined.Based on the wind tunnel test of the rigid segment model,the shape coefficient of catenary in different arrangement forms reflected in single cable,double cable,contact line,single cable single line and double cable single line was determined.According to the correction coefficient of the test,the design wind load value calculated by the correction method in this paper was used to compare with the standard value.The results show that with consideration of truss beam section and wind barrier of the bridge,the wind speed correction coefficient at the contact line position and cable position on the bridge deck is improved to 1.13 and 1.14,respectively.It can be seen that the bridge section and the wind barrier will improve the design wind speed of the catenary.According to the envelope value of different wind speed conditions,the shape coefficient of catenary in different layout forms is 1.4 for contact line,1.5 for single cable and 1.75 for double cable,which increased obviously compared to the current specification of 1.2.The design wind load of contact line,single cable and double cable calculated by the correction coefficient of test are 1.46 times,1.6 times and 1.86 times of the current code,indicating that the design wind load value of bridge catenary will be significantly higher than that of ordinary catenary.The research results can provide a reference for the wind load value in the design stage of bridge catenary and support for the revision of electric-railway-catenary specification in China.
作者
代笑颜
牛华伟
杨佳
陈奋飞
陈政清
DAI Xiaoyan;NIU Huawei;YANG Jia;CHEN Fenfei;CHEN Zhengqing(Key Laboratory for Wind and Bridge Engineering of Hunan Province,Hunan University,Changsha 410028,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)
出处
《铁道科学与工程学报》
EI
CAS
CSCD
北大核心
2023年第8期2794-2802,共9页
Journal of Railway Science and Engineering
基金
国家自然科学基金面上项目(52178477)。
关键词
桥梁接触网
设计风速
设计风荷载
桥梁断面修正系数
体型系数
bridge contact network
design wind speed
design wind load
bridge section correction factor
body type factor
