By the method of Hilbert-Huang transform(HHT),this article defines an instantaneous frequency time history of seismic acceleration record,which can to some extent quantify the frequency-non-stationary characteristics of original acceleration record.
利用HHT方法定义了一种地震加速度记录的瞬时频率时程,该瞬时频率时程能够在一定程度上将原始加速度记录的频率非平稳特性予以量化。