沿海高耸结构台风风压高度变化系数取值初探
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（1 同济大学建筑工程系, 上海 200092； 2 西安大略大学土木与环境工程学院, 安大略省N6G 5B9；3 华东电力设计院，上海 200001）［摘要］ 台风边界层风场特性是决定受台风影响较大的沿海地区高耸结构风荷载取值的一个主要因素。实际观测到的台风边界层风剖线和《建筑结构荷载规范》（GB 50009—2012）中幂函数律或对数律所描述的风剖线有一定的差别。通过利用下放探空对台风边界层风场的测量数据（1997~2010年），在已有的台风风剖线模型的基础上，拟合了下放探空实测的风速数据并和荷载规范中的幂函数律或对数律所计算的风剖线进行了比较，对比结果表明：荷载规范的计算方法在一定的台风条件下，在100～250m范围内低估了风速的高度变化，造成在台风风荷载作用下，离海岸较近的高耸结构(100m以上)按荷载规范计算的风荷载值会偏小。［关键词］台风风荷载; 高耸结构; 下放探空; 平均风剖线; 风压高度变化系数中图分类号：TU312+.1 文献标识码：A 文章编号：1002-848X(2013)24-0084-05Study on hurricane height variation factor of wind pressure of coastal high-rise structuresShen Zhirong1, Li Sunwei2, Ni Yang3（1 Department of Building Engineering, Tongji University, Shanghai 200092, China; 2 Department of Civil and Environmental Engineering, University of Western Ontario, OntarioN6G 5B9, Canada; 3 East China Electric Power Design Institute, Shanghai 200001, China）Abstract: Wind property of the hurricane boundary layer is one of the key factors in determining wind loads acted on high-rise structures in coastal hurricane-prone regions. The wind profile described by the conventionally used power law or log law in the Load code for the design of building structures（GB 50009—2012）is noticeably different from that implied by observations established in the hurricane boundary layer. By using the dropsonde measurement data gathered during 1997~2010 years, the wind velocity data of dropsonde measurement was fitted based on existing wind profile model. Fitted wind velocity data is compared with that calculated by power law or log law in the code. Results show that the calculating method of the code underestimates the wind velocity height variation within 100～250m under certain hurricane wind conditions, which leads to smaller wind load value acted on coastal high-rise structures above 100m when the code calculating method is used.Keywords: hurricane wind load; high-rise structure; dropsonde; mean wind profile; height variation factor of wind pressure作者简介：沈之容，博士，副教授，Email：shenzhirong@tongji.edu.cn。参考文献［1］徐旭,刘玉. 高耸结构在台风作用下的动力响应分析［J］.建筑结构，2009，39（6）:105-109.［2］葛耀君, 赵林, 项海帆. 基于极值风速预测的台风数值模型评述［J］.自然灾害学报，2003，12（3）：31-40.［3］赵林,朱乐东,葛耀君. 上海地区台风风特性Monte-Carlo随机模拟研究［J］.空气动力学学报，2009，27（1）:25-31.［4］GB 50009—2012 建筑结构荷载规范［S］. 北京：中国建筑工业出版社，2012.［5］FRANKLIN J L, BLACK M L, KRYSTAL V. GPS dropwindsonde wind profiles in hurricanes and their operational implications.［J］. Weather & Forecasting,2003，18:32-44.［6］HOCK T F, FRANKLIN J L. The NCAR GPS dropwindsonde ［J］. Bulletin of the American Meterological Society, 1999，80:407-420.［7］POWELL M D, VICKERY P J, REINHOLD T A. Reduced drag coefficient for high wind speed in tropical cyclone［J］. Nature, 2003， 422:279-283.［8］VICKERY P J, WADHERA D, POWELL M D, et al. A hurricane boundary layer and wind field model for use in engineering application［J］.Journal of Applied Meteorology and Climatology, 2009, 48:381-405.［9］KEPERT J. The dynamic of boundary layer jet with in tropical cyclone, Part I: linear theory ［J］. Journal of the Atmospheric Sciences，2001, 58:2469-2484.［10］ZHANG J, DRENNAN W M, BLACK P G, et al. Turbulence structure of the hurricane boundary layer between the outer rain bands ［J］. Journal of the Atmospheric Sciences, 2009，66:2455-2467.［11］ZHANG J, ROGERS R F, NOLAN D S, et al. On the characteristic height scales of the hurricane boundary layer［J］. Monthly Weather Review, 2011，139:2523-2535.
