完全非平稳地震动演化功率谱模型及其工程应用

基于平稳地震动过程的过滤白谱功率谱模型，提出一种能够实现时变谱能量描述的完全非平稳时变功率谱参数化模型，并通过参数识别获得具有工程意义的模型参数。采用基岩滤波器对K-T谱进行修正，使得时变谱参数具有明确的物理意义，并更加符合基岩地震动的物理特性；基于广义谐和小波变换得到地震波的时频分布，并通过Spanos-Tratskas方法估计出实际地震动的目标时变功率谱，引入遗传算法及二次优化技术，拟合时变参数的数学表达式，建立完全非平稳的地震动时变功率谱模型，模型参数识别过程采用了日本KIK-net强震数据库，并将其按照我国场地类别重新分类，最后验证该模型的有效性与适用性。该文提出的地震动随机模型为更加准确地描述地震动提供了参考，并为完全非平稳地震波的生成提供了依据。

Evolutionary power spectral model for the fully non-stationary groundmotions and its engineering application

Based on the power spectral model of filtered Gaussian white noise which is in the stationary earthquake process, the parametric model of fully non-stationary time-varying power spectrum is developed for describing time-varying spectral energy, and a model parameter with engineering significance is obtained through parameter identification. Firstly, the use of bedrock filter to modify the K-T spectrummakes the time-varying spectral parameters have a clear physical meaning and which is more consistent with the physical characteristics of the bedrock ground motion. Furthermore, the time-frequency distribution of the seismic is acquired on account of the generalized harmonic wavelet transform, and the time-varying power spectrum of the actual ground motion is estimated by the Spanos-Tratsk as method. At last, genetic algorithms and second optimization technology are introduced to fit mathematical expressions of time-varying parameters, and a fully non-stationary time-varying power spectral model of ground motion is established. The Japanese KIK-net strong earthquake database is adopted to identify the model parameters, which is reclassified according to the site category in China. Finally, the validity and applicability of the model are verified by the spectral representation method. The ground motion random model proposed in this paper provides a more accurately reference for describing the earthquake, and also provides a basis for the simulation of fully non-stationary ground motion.