台风作用下低矮房屋屋面角部峰值压力实测研究  

Full-scale measurements of peak pressures on a flat roof corner zone of a low-rise building during typhoons

作　　者：胡尚瑜[1,2] 李秋胜[1,3] 黄建平[1] 戴益民[1] 李正农[1] 

机构地区：[1]湖南大学建筑安全与节能教育部重点实验室,湖南长沙410082 [2]桂林理工大学,广西桂林541004 [3]香港城市大学,中国香港999077

出　　处：《土木工程学报》2012年第8期15-24,共10页China Civil Engineering Journal

基　　金：国家"985"工程;国家自然科学基金重大研究计划(90815030);"十一五"国家科技支撑计划项目(2006BAJ03B04-02)

摘　　要：通过研制的可移动平坡屋面实验房及台风测试系统,开展了近地登陆台风风场和房屋表面风压现场实测,主要研究近地边界层登陆台风风场特性和低矮房屋风效应。主要根据1003号"灿都"台风的实测风速和风压数据,研究近地台风风场湍流特征和屋面角部峰值负压。分析来流方向不同地貌状况和台风不同区域的近地10m高度的湍流度、阵风因子、湍流积分尺度等湍流特征参数;探讨实验房屋面角部区域风压分布特征和角部区域峰值压力时间和空间的平均效应。在斜向风作用下迎风屋檐角部边缘区域测点具有较大的峰值负压和脉动风压,实测最小峰值负压为-4240.0Pa,峰值负压系数最小值为-13.5,风压系数概率分布为非高斯分布。评估了来流不同湍流强度和湍流积分尺度对角部区域风压的影响。并运用非高斯峰值因子极值分析方法对角部区域峰值负压进行极值分析,最后将角部区域风压系数的实测值及极值分析值与现行ASCE 7-10规范规定值进行比较,现行ASCE 7-10规范相对低估其屋檐角部边缘区域的峰值负压系数。Abstract： monitor the wind velocity field and associated building surface pressures during typhoon landfalls. The major objective of the field study is to further understand typhoon-generated wind characteristics and wind effects on the low-rise building under extreme wind conditions. This paper presents the analysis results of wind characteristics and extreme suction pressure coefficients on a roof comer zone based on the field measured data obtained from the instrumented low-rise building during Typhoon Chanthu. The surface level wind turbulence characteristics such as gust factor, turbulence intensity and integral scale are quantified in different terrain exposures and different portions of the typhoon. Detailed analysis of the mean, peak and standard deviation of pressures measured on a roof comer zone is conducted to investigate the pressure distribution characteristics. Moreover, the effect of spatial and temporal averaging on peak pressures is also discussed. The windward leading edge on the comer was consistently subjected to the most severe suction pressures and fluctuation pressures for quartering winds. The measured extreme suction pressure was -4240Pa and the minimum negative peak pressure coefficient was -13.5. The probability distribution of the normalized fluctuating pressure coefficient on the corner zone in conical vortex flow regions is non-Gaussian. The effects of large turbulence scale and turbulence intensity on the roof pressures are evaluated for conical vortex flow regime in oblique direction. The extreme value analysis is performed using an automated procedure to determine the peak suction pressure coefficients. The estimated extreme peak pressures are compared with those stipulated by the ASCE 7-10 Standard. The observed and estimated suction pressure coefficients on the windward leading edge on the comer area exceeded the values recommended by ASCE 7-10 Standard.

关 键 词：低矮房屋 现场实测 风荷载 峰值压力 极值分析 

分 类 号：TU312.1[建筑科学—结构工程]