摘要
国内高速铁路网不断完善,沿海铁路海湾地形的风场特性亟待研究。基于福厦客专—泉州湾跨海大桥桥址处40 m风塔,实测获得了201911台风“白鹿”影响下的泉州湾近地风场实测数据。基于经验模态分解(EMD)技术得到了台风全过程时变平均风及相应脉动风样本,采用四参数风速功率谱模型拟合了台风纵向、横向及竖向功率谱,在此基础上对拟合参数进行了平均风速影响分析及概率密度分析。建立了38 m高度处台风演化功率谱并与同风速范围的相关规范建议风谱进行了对比。研究表明:四参数风谱模型能较好适用于实测台风风谱,各拟合参数随平均风速变化并不显著,拟合参数B随A呈指数型增长;核密度估计方法能较好拟合风谱参数的概率密度分布,拟合谱中的A参数概率密度近似对数正态分布,而B,C及α参数则与正态分布接近;测点接近7级风圈时所测脉动风湍流动能较位于风圈内时强;规范风谱并不能很好地反映“白鹿”台风引起的跨海大桥主梁高度处湍流功率谱密度(PSD)特征。
With development of high-speed railway network in China,wind field characteristics of gulf terrain along coastal railway need to be studied.Based on one 40 m wind mastnear the bridge site of Quanzhou Bay Cross-Sea Bridge of Fuzhou—Xiamen passenger dedicated line,the near ground wind fielddata under the influence of“Bailu”were obtained.The time-varying average wind and corresponding fluctuating wind samples of the whole process of typhoon were obtained based on empirical mode decomposition(EMD),and a four-parameter power spectrum model was used to fit thepower spectrum of typhoon turbulence.Then the change law between spectrum parameter and mean wind velocity,probability density distribution analysis of spectrum parameter were conducted.Finally,the evolution power spectrum of typhoon turbulence at 38 m height was analyzed and compared with normative spectrum.The results show that:the four parameter model can be fitted to the measured wind spectrum of typhoon well,and the parameters are not significantly changed with the average wind velocity,the parameters A and B are exponential mapped;the kernel density estimation method is applicable to the estimation of probability density distribution of the wind spectrum parameters,and the parameter A is approximately lognormal distribution,while the parameters B,C,and α are near to normal distribution in this study;the turbulent energy is stronger when outer-region circulation of typhoon approaches the bridge site;normative spectrum can not reflect the turbulence power spectral density(PSD)characteristics well at the height of the main girder of the sea-crossing bridge under the influence of typhoon“Bailu”.
作者
徐智伟
王劲松
饶惠明
戴公连
XU Zhiwei;WANG Jinsong;RAO Huiming;DAI Gonglian(School of Civil Engineering,Central South University,Changsha 410075,China;Southeast Coastal Railway Fujian Co.,Ltd.,Fuzhou 350013,China;National Engineering Lab for Construction Technology of High Speed Railway,Changsha 410075,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第16期253-260,共8页
Journal of Vibration and Shock
基金
中国铁路总公司科技研究开发计划(2017G006-N)。
关键词
台风“白鹿”
海湾地形
湍流功率谱(PSD)
风谱拟合
核密度估计
typhoon“Bailu”
gulf topography
turbulence power spectral density(PSD)
spectrum fitting
kernel density estimation
