Empirical Models for Fourier Amplitude Spectrum of Ground-Motion Calibrated on Data From the Iranian Plateau
Description:
Ground motion models (GMMs) are commonly employed in engineering seismology to predict ground motion intensities. Most GMMs typically predict the response spectral ordinates, such as spectral acceleration, for a single-degree-of-freedom oscillator due to their widespread use in engineering design. The functional forms of the GMMs for response spectra are constructed based on principles derived from the Fourier spectral concept. Presuming the applicability of Fourier spectral concepts in the response spectral domain might lead to physically inexplicable outcomes. This study employed a mixed-effects regression technique to introduce four models for predicting the Fourier amplitude spectrum. These models explore the influence of incorporating random-effect event and station terms and variations in employing the mixed-effects regression technique in either one or two steps, using either a truncated dataset or the entire dataset (nontruncated dataset). The models are developed based on data from Iranian strong motion. All datasets comprise 2581 three-component strong ground motion records derived from 424 events with magnitudes ranging from 4.0 to 7.4. These records span from 1976 to 2020 and involve 706 stations.
In contrast, the truncated dataset has fewer records, events, and stations, specifically 2071, 408, and 636. We employed simple functional forms for four models, incorporating a restricted set of predictors, which include moment magnitude (Mw), Joyner-Boore distance (Rjb), and time-averaged shear-wave velocity in the top 30 m (VS30). The style-of-faulting term was omitted from the final functional forms based on statistical analyses.
Session: The 2023 USGS National Seismic Hazard Model and Beyond [Poster Session]
Type: Poster
Date: 5/1/2024
Presentation Time: 08:00 AM (local time)
Presenting Author: Mehran
Student Presenter: No
Invited Presentation:
Authors
Mehran Davatgari Tafreshi Presenting Author Corresponding Author mdvtgrtf@memphis.edu University of Memphis |
Shahram Pezeshk spezeshk@memphis.edu University of Memphis |
Sanjay Singh Bora s.bora@gns.cri.nz GNS Science |
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Empirical Models for Fourier Amplitude Spectrum of Ground-Motion Calibrated on Data From the Iranian Plateau
Session
The 2023 USGS National Seismic Hazard Model and Beyond