摘要
本文详细评述了现今常用的几种加速度反应谱与功率谱的转换关系，对于小阻尼单质点体系而言，考虑到输入地震动是一非平稳的随机过程，又由于其传递函数的窄频带滤波特性，它的加速度反应将是一窄频带的非平稳随机过程。对于峰值系数水平的超越不是独立的，而是成群超越。据此本文考虑非平稳效应和对峰值系数水平的成群效应，对前人的转换关系进行了修正，并基于随机振动理论，给出了对工程上常用的频率平稳、强度非平稳的地震动模型的功率谱和反应谱的转换关系。此转换关系对于长、短持时的地震动记录和反应谱长、短周期部分以及不同阻尼比的反应谱都能给出精度较高的结果。
Several relationships between power spectral density functions and response spectra of earthquake ground motions are summarized in this paper. As for a single-degree-of-freedom system with small damping ratio, its response to non-stationary earthquake ground motion would be non-stationary narrowband random process, because the function of the system is a narrowband filter. Based on the random vibration theory, this paper presents a new relationship between power spectral density functions and response spectra of earthquake ground motion which is non-stationary in amplitude but stationary in frequency contents. Both the effect of non-stationary and that of narrowband are considered in this relationship. This relationship can provide more accurate results than other relationships for different duration ground motions and different damping ratios of response spectra in a wide frequency area which is interested in earthquake engineering.
出处
《地震工程与工程振动》
CSCD
北大核心
2001年第2期30-35,共6页
Earthquake Engineering and Engineering Dynamics
基金
国家自然科学基金资助项目(59708011)
地震科学联合基金重点资助项目(95-07-441)
