杨松涛  叶列平  钱稼茹
    （清华大学土木工程系  北京 100084）

[提要]  研究了地震地面运动的加速度谱、位移反应谱与富里叶谱之间的对应关系，结果表明，加速度谱可较好地表现地震动高频部分的特性，位移谱可较好地表现地震动低频部分的特性。提出了位移谱特征周期Tgd的概念，并以弹性位移谱上Tgd对应的点为基准点对位移谱进行标准化，较好地消减了不同地震动对位移谱曲线形状的影响。最后，根据多条地震动的计算结果，总结了此标准化方法下的平均位移谱的特征，为基于位移抗震设计理论的研究提供了基础。
[关键词]  地震反应  位移谱  特征周期  标准化  单自由度体系

The correlation among the peaks of acceleration spectra, displacement spectra and input ground acceleration Fourier amplitude spectra was investigated for single-degree-of-freedom( SDF)system. The results showed that at short periods acceleration spectrum could reflect the spectral characteristics of ground oscillation well, while at long periods displacement spectrum could do that well. The problem of standardizing for displacement spectrum was studied.A concept of characteristic periods of displacement spectra was proposed, which resulted in reducing the effects of different ground motions on the displacement spectrum shape. Finally, based on standardized displacement spectra calculated under different ground motions, the characteristics of elastic and inelastic displacement spectra were concluded.
Keywords: earthquake response; displacement spectrum; characteristic period; single degree freedom system