摘要
在大气边界层中,科里奥利力会导致风向随离地高度的增加而发生偏转,这会对建筑风荷载产生显著影响。许多学者研究了偏转风场下建筑风荷载特性,但模拟偏转风场的过程十分复杂。本文采用模型扭转的方法替代风场偏转来研究问题,即在无偏风场下按埃克曼螺线方式扭转高层建筑,分析其风荷载,并与偏转风场下的非扭转高层建筑的风荷载进行比较。本文基于大涡模拟分析问题,结果表明,无偏风场下按埃克曼螺线方式扭转的高层建筑的风荷载和在偏转风场下的非扭转高层建筑的风荷载在大多数立面上的平均风压系数、顺风向层风力系数、顺风向基底弯矩系数近似相等,但在脉动风压、横风向风力等方面存在差异。因此,以模型扭转来替代风场偏转的方法能用于分析建筑的平均风荷载,横风向脉动和局部的风荷载结果可作为参考。
The wind direction in the atmospheric boundary layer will twists with height due to the Coriolis force,known as the Ekman spiral,which can have a significant impact on building wind loads.At present,many researchers have studied the wind load characteristics of buildings under twisted wind fields,but the process of simulating twisted wind profiles is complex and difficult.Therefore,in this paper this problem is studied with twisting the model instead of the twisted wind field test method.Based on the large eddy simulation,this paper investigates whether the wind loads of tall buildings twisted by Ekman spiral mode in the conventional untwisted wind field can be equivalent to those of untwisted tall buildings in the twisted wind field.The results show that the mean wind pressure coefficienton most façades,the mean and fluctuating value of the local wind force coefficient and the along-wind base moment coefficient are approximately the same,but the fluctuating wind pressure,crosswind wind force are different.The method can be used to analyze the mean wind loads of buildingsin the along-wind direction,but while analyzing the local wind load characteristics or the wind loads in the crosswind direction,this method couldbe used as a reference.
作者
贺斌
全涌
冯成栋
顾明
HE Bin;QUAN Yong;FENG Chengdong;GU Ming(College of Civil Engineering,Tongji University,Shanghai 200092,China;School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300131,China)
出处
《建筑结构》
北大核心
2023年第S02期2175-2181,共7页
Building Structure
基金
国家自然科学基金(51778493)
土木工程防灾国家重点实验室自主研究课题基金(SLDRCE19-B-13)。
关键词
高层建筑
风荷载
埃克曼螺线
偏转风场
大涡模拟
high-rise building
wind load
Ekmanspiral
twisted wind field
large eddy simulation
