市街地低層部における風の性状と風環境評価に関する研究-II : 強風時における市街地低層部の変動風の性状

概要

論文の詳細を見る
This paper describes the characteristics of turburence of city wind at ground level (H=1.5〜8.0m). The measurements were conducted at the street around a high-rise apartment house in the built-up area in Tokyo. The main results are as follows. 1) The frequency of instantaneous wind direction distributes narrowly at points where wind velocity is high, but it distributes widely at points where wind velocity is low. 2) The frequency distributions of scalar value of instantaneous wind velocity are not expressed by Gaussiun distribution at point near the ground. 3) The value of power spectrum of the wind velocity at the ground level does not decrease at the high frequency region. Consequently, values of gust factor near the ground are larger than those at much higher level. 4) The relation between the gust factor and the ratio of mean wind velocity to the reference point is given by the equations, shown below. G_t=A_tR′-α_t(Z′/Z_D)-α_t/n A_t=(t/T)^<-0.08> α_t=-0.065ln(t/T) Here, Z_D : 58.1m t : averaging time of gust wind (sec) T : sampling duration of mean wind velocity (=600 sec) Therefore, when the velocity ratio is given by the wind tunnel test, the gust factor can be found by above equations.
社団法人日本建築学会の論文
1982-04-30