Simulation of Artificial Near-Fault Ground Motions Based on the S-Transform

S transform is one of the effective modern time-frequency analysis techniques. A new method of applying S transform to simulate artificial near-fault ground motions is presented. The artificial near-fault ground motions are simulated by combining filtered real or artificial far-fault ground motions by time–frequency filter with equivalent pulse, which can reflect the local characteristics of site and the pulse characteristics of near-fault ground motions. Numerical analysis shows the time-frequency characteristics of artificial near-fault ground motions are similar to that of parents ground motions, and the PSD in high frequency range is compatible with a target PSD of code for seismic design of buildings of China. The PGA of artificial near-fault ground motions are identical to the PGA corresponding to earthquake intensity in this code. So the artificial near-fault ground motions presented in the paper can be used for seismic analysis of the structures in near-fault seismic zone.