Physical random function model of ground motions for engineering purposes

A physical random function model of ground motions for engineering purposes is presented with verification of sample level. Firstly, we derive the Fourier spectral transfer form of the solution to the definition problem, which describes the one-dimensional seismic wave field. Then based on the special models of the source, path and local site, the physical random function model of ground motions is obtained whose physical parameters are random variables. The superposition method of narrow-band harmonic wave groups is improved to synthesize ground motion samples. Finally, an application of this model to simulate ground motion records in 1995 Kobe earthquake is described. The resulting accelerograms have the frequency-domain and non-stationary characteristics that are in full agreement with the realistic ground motion records.