Numerical Simulation of Seismic Waves with Peak Arrival Time and Amplitude-Frequency Correlation

To improve the accuracy with which the non-stationary intensity characteristics of artificial acceleration-time-history curves are determined, a method of adjusting the frequency correlation between the artificial peak arrival time and amplitude spectrum is proposed. A calculation method for determining the peak arrival time to reflect the physical meaning of the phase-difference spectrum was first deduced. Subsequently, the amplitude-distribution characteristics corresponding to the peak arrival times for different durations of natural earthquakes were analyzed. In accordance with the distribution characteristics of the reference amplitude, the frequency distribution of the artificial peak arrival time was divided into four parts: the beginning, strong-earthquake, attenuation, and tail sections. By adjusting the arrival frequency of peak points for the different earthquake durations considered, the corresponding relationship between the artificial peak arrival time and amplitude spectrum was determined to be more consistent with the general law of natural earthquakes. The sample calculation described in this paper demonstrates that adjusting the frequency correspondence between the artificial peak arrival time and amplitude spectrum greatly improves the accuracy of the non-stationary intensity characteristics of artificial acceleration-time-history curves.