风的动力作用

本文从工程角度出发，阐述了风谱的表达、意义及应用，并对风载荷的稳态及脉动部分都进行了讨论，脉动风载荷的计算与前人不同，文中保留了和频项的贡献，对风载荷的各组成部分提供了量的概念。结果表明，风载荷的脉动峰值有可能是平均值的２．３６倍，利用阵风风速计算出的风载荷，数量上接近风载荷的±值，一阶与二阶风载荷的脉动频率都极低，对低频系统应加以注意。

THE DYNAMIC EFFECT OF WIND

With an engineering point of view, the essence and expression of wind spectrum as well as its dynamic effect on structures are introduced. Both steady and oscillating parts of wind force are theoretically and numerically discussed with a characteristic of keeping sum-frequency part in second order wind force.The magnitudes of each component in total wind force are compared. Results show that the peak value of wind force is about 2. 36 times the mean froce,and the force calculated by gust wind velocity will close to the average of the highest one-tenth of the fluctuating wind force in quantity it also shows that both oscillating frequencies of first and second order wind forces are very low,so one should pay attention to its dynamic effect in some low fequency motion system.