介绍了风的基本特性、风速模拟的谐波叠加法原理,引入快速傅里叶FFT改进的谐波叠加法.采用改进后的谐波叠加法模拟桅杆结构沿杆身高度不同位置处的多维风速时程,根据风速、风压间的关系将其转化为结构分析所需的风荷载时程.并与相同条件下谐波叠加法模拟风速时程的过程进行了对比,结果表明两种方法的模拟功率谱与目标功率谱均比较吻合,但改进后的谐波叠加法运算效率明显高于谐波叠加法.
This paper has introduced the basic properties of wind and the principle of harmonic wave superimpose method for wind velocity simulation,as well as the improved method by introducing FFT (Fast Fourier Transform)in harmonic superimpose wave method.Wind velocity time series along the height of guyed-mast has been simulated with the improved method,which has been transformed into wind load according to the relationship between wind velocity and wind pressure.A comparison to the simulation of harmonic wave superimpose method with the same condition has been made.The results shows that the simulating spectrums of the two methods are both matched the objective spectrum well.But the efficiency of improved method is obviously higher than that of harmonic superimpose wave method itself.