考虑极值风速方向性的围护结构设计风荷载概率估计方法研究  

A probabilistic method for estimating extreme wind pressure on structures considering direction effect of extreme wind speed

作　　者：张秉超 全涌[1] 顾明[1] ZHANG Bingchao, QUAN Yong , GU Ming(State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, Chin)

机构地区：[1]同济大学土木工程防灾国家重点实验室

出　　处：《建筑结构学报》2018年第4期1-7,共7页Journal of Building Structures

基　　金：国家自然科学基金面上项目(51278367)

摘　　要：对于围护结构的设计风荷载（一定重现期的极值风压）,目前工程上普遍采用最不利值方法进行估算,这类方法不符合概率统计意义。只有统筹考虑极值风速和极值风压系数的随机性、方向性及相关性才能给出较为准确的设计风荷载。为此,提出一种全面考虑极值风速和极值风压系数随机性和方向性的围护结构设计风荷载概率估计方法。首先,提出了极值风压计算所需的三个要素,即各风向的极值风速分布、Cook-Mayne极值风压系数和风向相关性;然后,通过极值风压的概率分布理论分析,给出一个以上述三要素为输入的计算过程简便实用的围护结构风荷载估算公式;最后,以上海地区一栋高层建筑为例,通过与工程上常用最不利值方法相比,验证了本文方法的精确性和实用性。The design wind load on building envelop, which represents the extreme wind pressure in a given return period, is generally estimated by the most unfavorable method in engineering application, which is not precise in the sense of probability. The relatively precise design wind loads can only be obtained when the characteristic of both the random values of wind speed and aerodynamic coefficient, such as their randomness, directivity and correlation, are taken into consideration. In view of this problem, a probabilistic method for estimating the design wind load on building envelope was proposed in this paper which had an overall consideration of the randomness and direction effect of the extreme wind speed and aerodynamic coefficient. The three main factors for estimating the extreme wind pressure, which were the distributions of directional extreme wind speed, the Cook-Mayne wind pressure coefficient and the information of the correlation among extreme wind speeds in different wind directions, were induced from the existing samples. Then, a formula for estimating extreme wind pressure was proposed based on the three main factors. The accuracy and practicability of the proposed method is verified by an example of a high-rise building in Shanghai, in which the results are compared to the most unfavorable values widely used in engineering work.

关 键 词：围护结构 风荷载 概率估计方法 风向性 相关性 

分 类 号：TU973.213[建筑科学—结构工程]