Generating Of Artificial Earthquake Ground Motion And Establishment Of Non-stationary Earthquake Ground Motion Model Based On Wavelet Packet Transform

Generating artificial earthquake ground motion is an important content of the earthquake engineering field. But most of the methods to generate artificial earthquake ground motion are based on uniform modulation model, which can not show the timefrequency nonstationarity. Therefore, to find a non-stationary seismic modeling method that can follow the-time-frequency distribution characteristics of real seismic is of great significance.In this paper, firstly puts forward a new method for Generating artificial earthquake ground motion, and the method is based on wavelet reconstruction theory and energy control concept. This method improves some defects of the old methods, and it is accurate and quick. And through matlab programming, this paper verifies the method has a high accuracy synthesis.Then, this paper puts forward a optimal selection principle for wavelet basis function,which includes qualitative selection and quantitative selection, and is uesd for the ground motion generating and analysis. For ground motion generating and analysis, the qualitative criteria should be different. This paper regards the frequency band energy average error values as the discriminant function, and analyzes 8 kinds of commonly used wavelet basis function by quantitative criteria.Finally in this paper, a large number of real seismic are collected for frequency domain analysis and time-frequency analysis, and then this paper simulates the Peng Lingyun power spectrum model. Based on the Priestley evolutionary spectra and Peng Lingyun power spectrum model, this paper establishes the time-varying power spectrum model. Based on above models, this paper establishes the non-stationary ground motion model based on time variable modified Peng Lingyun power spectrum model, which can accurate express the characteristic of real seismic, can be used for practical engineering,and has a certain theoretical value and engineering significance.