The possibility of inconsistencies among reference wind speeds in national border areas has been discussed at Workshops on Regional Harmonization of Wind Loading and Wind Environmental Specifications in Asia-Pacific Economies (APEC-WW). To identify the details of this issue, this study explores a unified approach for reasonably comparing reference wind speeds. First, we review an approach applied to averaging time conversions of wind speeds, in which the statistical distribution of the maxima of a stationary random function is derived. Next, we examine turbulence spectra and scales in 176 codes and standards around the world. Then, we compute peak factors for obtaining wind speeds with various averaging times, applying 11 combinations of turbulence spectra and sampling lengths, and confirm reasonable results in comparisons with those obtained in previous studies. Finally, we discuss some practical considerations in conversions and comparisons of reference wind speeds through some practical application examples.

The relation between the distribution of roof damaged by Typhoon Jebi, 2018 and the maximum wind speed during passing this typhoon (Vmax) were investigated by Geographic Information System. The variation of the damage ratio given as the ratio of the number of blue tarps to the number of houses in a survey mesh was very wide and did not show the clarify relationship with Vmax. Therefore, the number of the damage mesh (survey mesh including at least one damage) was counted and the relation between the cumulative number of damage mesh for the squared Vmax was investigated based on the weakest link probability model. As the result of this investigation, it was clarified that distribution of cumulative number of damage mesh was fit very well to Weibull distribution which is the solution of the weakest link probability model, and Weibull parameters were controlled by the housing density.

This study aims to validate prediction of pollutant dispersion in urban area based on wind tunnel experiment. For this purpose, wind tunnel experiments and filed measurements of tracer gas dispersion were conducted in the campus of Tokyo Polytechnic University, and their results were compared. In addition, wind tunnel experiment was carried out under various conditions of experimental model scale, wind speed, and pollutant emission rates to confirm similarity law. The normalized concentration obtained by the wind tunnel experiments agreed well with the field measurement data. It was also confirmed that the normalized non-dimensional concentration was nearly independent of experimental model scale, wind speed, and pollutant emission rate.