EVALUATION OF SOURCE, PATH AND SITE EFFECTS IN STOCHASTIC METHOD OF SIMULATING STRONG GROUND MOTION FOR SARPOL-E ZAHAB, IRAN EARTHQUAKE OF 2017

In this study, simple and powerful method for simulating ground motions that often entiteled ‘‘stochastic method’’ has been used to generate the strong ground motions. The stochastic method is useful for simulating the higher-frequency ground motions of most interest of engineers (generally, f > 0.1 Hz), and widely is used in two ways (1) point-source and (2) finite-source. Here, point-source method has been used to predict ground motions for some stations of strong ground motion of Sarpol-e Zahab earthquake (Iran, 2017). Sarpol-e Zahab is a region of Iran in which recordings of motion from potentially damaging earthquakes are not available, so stochastic method is useful to simulate strong ground motions of this region. For stochastic simulation, theoretically Fourier acceleration spectrum is into simple functional form and be made from three following effects: (1) source-effect (2) path-effect and (3) site-effect. Until now, seismologists and earthquake engineers have developed numerous equations for this three effect. In this study, we have examined many equations to find out best Fourier acceleration spectra as frequency-domain results and subsequently acceleration, velocity and displacement response spectra as time-domain results for some stations of Sarpol-e Zahab earthquake. From structural engineering point of view, the seismic influence of earthquake on structural and geotechnical damage is shown with acceleration, velocity and displacement seismic response spectra. Therefore, finally to compare stochastic simulation results with NGA-West2 as GMPEs results and spectra from recorded acceleration as real results, we have used acceleration, velocity and displacement response spectra.

کلیدواژه ها:

Source effects ، Quality Factor ، Site effects ، Stochastic simulation ، Strong ground motion