Publication Date:
2017-04-04
Description:
We simulated strong motion records from the Umbria-Marche, Central Italy earthquake (Mw 6) of September 1997 using a frequency-dependent S-wave radiation function. We compared the observed acceleration spectra, from strong-motion instruments located in the near field and at regional distances, with those simulated using the stochastic modeling technique of Beresnev and Atkinson (1997, 1998), and modified to account for a frequency dependent radiation pattern correction. By using the frequency-dependent radiation function previously obtained by Castro et al. (2006) we reduced the overall fitting error of the acceleration spectra by about 9%. In general, we observed that the frequency-dependent radiation pattern correction has a small effect on the spectral amplitudes compared with site effects, which is an important factor controlling the strong-motion records generated by the 1997 Umbria-Marche earthquake. In addition, we modeled the observed ground-motion records using the dynamic corner frequency model of Motazedian and Atkinson (2005) to reproduce the directivity effects, reducing the average error of the spectral amplitudes by 24%. We concluded that although the frequency-dependent radiation pattern correction affects the frequency content of the spectral amplitudes simulated, site and directivity effects are more relevant.
Description:
In press
Description:
4.1. Metodologie sismologiche per l'ingegneria sismica
Description:
JCR Journal
Description:
open
Keywords:
strong-motion simulation
;
04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
manuscript