Generation of Spectrum-Compatible Earthquake Motion Using Wavelet Transform

In this paper, a new method for generating artificial earthquake motions is proposed, in which one can explicitly design the time-frequency characteristics of the earthquake as well as its response spectra. First, it is shown that the velocity response spectrum at a specific period can be interpreted as the maximum amplitude of the wavelet transform in which the velocity impulse response function of a single-degree-of-freedom system is used as the analyzing wavelet. Using this relationship, a spectrum-compatible artificial earthquake motion with the desirable time-frequency characteristics is generated in the wavelet domain by an iterative correction-projection scheme. Some illustrative examples are investigated to demonstrate the capability and the practicability of the proposed scheme.