为掌握中国东南沿海台风登陆过程近地面风速变化规律及影响因素，根据2005年浙江省东海塘观测塔和上海市芦潮港观测塔分别实测得到的2次典型强台风（麦莎（ Matsa 0509）和卡努（ Khanun 0515））登陆时段距地面10 m高度处的实时风速记录资料，计算了不同时距风速的转换系数及其概率分布．计算结果表明，风速时距转换系数服从广义极值分布，V3 s／V10 min服从极值Ⅱ型分布，V30 min／V10 min以及V1 h／V10 min服从极值Ⅲ型分布．分别处于台风远端和近端的两处观测塔的实测记录表明，A类场地下，在台风影响范围内，工程场地处台风气候条件下10 m高度处风速时距转换系数的取值及其概率分布基本保持稳定，基本不受台风路径、台风强度变化、观测点在台风风场中的相对位置以及台风登陆与否的影响．A类场地的台风气候条件下，采用基于概率统计的具有一定保证率的风速时距转换系数取值，能够为建筑结构抗风性能设计提供可靠保证．%To obtain the variation of wind speed near ground at the southeastern coastal area of China and its influence factors during the landfall process of typhoons, wind speed samples at 10 m during the landing of two strong typhoons(Typhoon Matsa 0509 and Typhoon Khanun 0515)were recorded by anemometer towers located at the regions of Donghaitang in Zhejiang Province and Luchaogang in Shanghai. Wind speed conversion factors of different time intervals and their probability distribution were calculated based on the sampling wind speeds. It is illustrated that wind speed conversion factors of different time intervals follow generalized extreme value distribution. V3 s/V10 min follows Frechet Distribution, while V30 min/V10 min and V1 h/V10 min follow Weibull Distribution. There are 2 anemometer towers, one is adjacent to the paths of typhoons, while the other one is far away from them. It shows that in typhoons’ condition for terrain A, values of wind speed conversion factor keep steady and the probability distribution functions of conversion factors hold similar distribution characteristics during the landing process of strong typhoons regardless of the paths of typhoons, variation of typhoon intensity, the distance between the anemometer tower and the typhoon center and the landfall state of the typhoon. Values for wind speed conversion factors for terrain A in the condition of typhoons based on the analysis of probability statistics provide the assurance of reliability for wind resistant design of structures.
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