ANALYSIS OF GUST FACTORS FOR USE IN ASSESSING WIND HAZARD

This paper presents a method of analysing wind data so that residual risks can be calculated when applying a mean wind criterion to a scenario which is sensitive to gusts. This requires an analysis of gust factor data, which has been undertaken for 10 years hourly data at a UK site. The data is shown to conform to a Fisher-Tippett type I distribution which is to be expected, since each hour's gust factor is itself an extreme value. However, it is found that the high gust factor values tend to diverge from the good fit for the lower values. Since it is these high values which dominate the residual risk, care must be taken in their extrapolation to ensure that results remain both realistic and conservative.