【摘要】 针对常规HHT功率谱存在能量泄漏的问题,提出基于正交化HHT变换来模拟地震波的方法。结合正交HHT对地震波局部谱密度的估计方法,以正交HHT时变功率谱作为目标谱并利用三角级数法来模拟非平稳地震记录。并通过对El Centro波和Landers波的模拟来研究样本强度和频率的非平稳特性。结果显示,模拟样本的时频特性与原记录相接近;任意一个样本过程的时变谱不一定符合目标谱,但是在统计意义上却严格符合目标谱。可以为某一强震记录补充大量具有相同统计特性的样本波,有利于结构随机响应时程分析。更多还原

【Abstract】 Simulation of seismic wave based on Orthogonal HHT is proposed in the paper.Firstly,the problem of energy leakage existing in conventional HHT power spectrum is presented.Integrated with the orthogonal HHT estimating local spectral density of earthquake ground motion,time-dependent power spectrum is used as target power spectrum and the trigonometric series is used to simulate record of non-stationary earthquake ground motion.The sample processes’ non-stationary characteristic of intensity and frequency is studied by simulating one acceleration record in El Centro and one acceleration record in Landers.Then,the conclusion on time-frequency character of sample according with that of record is verified by the simulation.Finally,the power spectrum of any sample process dose not necessarily accord with the target spectrum,but statistically,it strictly accords with the target power spectrum.As a result,a lot of earthquake samples having same statistical characteristic as well as the real record can be simulated and it is benefit to history analysis of structural random response.更多还原