【摘要】 在介绍地震动描述沿革的基础上,分析了使用时变谱密度,即局部谱密度来刻画具有时频非平稳特性的地震动的必要性。从理论上详细比较了小波变换与其它几种局部谱密度估计方法,指出利用小波变换来估计局部谱密度比其它方法精度更高,速度更快,使得方便高效地将局部谱密度应用在地震工程和结构抗震的诸多领域成为可能。更多还原

【Abstract】 The history of investigation and description for earthquake ground motion is introduced, it is shown that the earthquake ground motion with non-stationary time-frequency characteristics should be depicted by time-dependent spectral density, i.e. local spectral density. By a detailed comparison of various local spectral density estimation methods, it is shown that wavelet transform is the best tool to estimate the local spectral density of earthquake ground motion regarding its precision and efficiency, and facilitates application of local spectral density to the ground motion modeling, structural analysis and the dynamic reliability evaluation.更多还原