최근 기상자료에 의한 지표면조도구분별 돌풍률 평가

Design wind speeds for estimating wind loading of structures were based on the 10 minute mean wind speed or the gust wind speed having 3 second averaging time. The 10 minute mean wind speed might be applied to estimate wind load of buildings and the 3 second gust wind speed might be applied to high frequency structures such as claddings. The gust wind speed is affected by the conditions of surroundings, so it convenient to estimate gust wind speed by the product of gust factor and 10 minute mean wind speed. This study estimates gust factor suitable for the surface roughness categories, which is reflecting a severe change of surface roughness by rapid urbanization process and recent abnormal weather by global warming. Wind speed values are established from data of 10-minute mean and 3 second gust wind speed collected at 68 meteorological offices recent past 40 years from 1973 to 2012 and surface roughness categories are used previous study result. For estimating gust factor, it is assumed that the range of maximum monthly value of mean wind speed has limited from 16㎧ to 18㎧ and gust factors have constant value, if wind speeds are below 16㎧ or over 36㎧. By the results of study, it is known that gust factors of surface roughness category C are similar to those of B and gust factors of surface roughness category D are different from other categories. Therefore, empirical formula of gust factor on surface roughness category B and C was suggested on the same type and on surface roughness category D was suggested on different type.