The synthesis of man-made ground motion considering the super-randomness
Xu Guodong~(1), Zhou Xiyuan~(1,2), Yan Weiming~(1), Dong Di~(1)(1.Beijing Key Laboratory of Earthquake Engineering and Structural Retrofit,Beijing 100022,China; 2.Institute ofEarthquake Engineering and Disaster Reduction, Beijing University of Technology, Beijing 100022, China)
According to the two important properties of the autocorrelation function, the paper proposes a method of creating the random noise in autocorrelation function through iterations and then gives a method to synthesize man-made seismic wave whose objective function is the autocorrelation function or the corresponding power spectra in consideration of so called super-randomness of ground motion caused by random noise in autocorrelation. It is indicated that the SS (sum of squares) of ground motion is more adaptable measurement of the ground motion severity rather than the peak ground acceleration (PGA) of ground motion while whose main phase can be regarded as a stationary random process. The Monte Carlo method was used to analyze the effect of the random noise part in auto-correlation on the amplitudeof man-made seismic wave and on the response spectra as well. Due to the zero contribution of the noise part of auto-correlation to the total power of seismic wave, the effect of the noise part on the man-made seismic wave's amplitude is insignificant. But because the noise part greatly changes the frequent-domain distribution of the power spectrum, the random part in autocorrelation function leads to some effect to certain extend on the response spectra.