An Equivalent Point‐Source Stochastic Simulation of the NGA‐West2 Ground‐Motion Prediction Equations

Research Article| March 06, 2018 An Equivalent Point‐Source Stochastic Simulation of the NGA‐West2 Ground‐Motion Prediction Equations Arash Zandieh; Arash Zandieh aLettis Consultants International, Inc., 4155 Darley Avenue #A, Boulder, Colorado 80305, arash.zandieh@live.com Search for other works by this author on: GSW Google Scholar Shahram Pezeshk; Shahram Pezeshk bDepartment of Civil Engineering, The University of Memphis, Engineering Science Building, Room 104A, Memphis, Tennessee 38152, spezeshk@memphis.edu Search for other works by this author on: GSW Google Scholar Kenneth W. Campbell Kenneth W. Campbell cCoreLogic, Inc., 555 12th Street, Suite 1100, Oakland, California 94607, kcampbell@corelogic.com Search for other works by this author on: GSW Google Scholar Author and Article Information Arash Zandieh aLettis Consultants International, Inc., 4155 Darley Avenue #A, Boulder, Colorado 80305, arash.zandieh@live.com Shahram Pezeshk bDepartment of Civil Engineering, The University of Memphis, Engineering Science Building, Room 104A, Memphis, Tennessee 38152, spezeshk@memphis.edu Kenneth W. Campbell cCoreLogic, Inc., 555 12th Street, Suite 1100, Oakland, California 94607, kcampbell@corelogic.com Publisher: Seismological Society of America First Online: 06 Mar 2018 Online Issn: 1943-3573 Print Issn: 0037-1106 © Seismological Society of America Bulletin of the Seismological Society of America (2018) 108 (2): 815–835. https://doi.org/10.1785/0120170116 Article history First Online: 06 Mar 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Arash Zandieh, Shahram Pezeshk, Kenneth W. Campbell; An Equivalent Point‐Source Stochastic Simulation of the NGA‐West2 Ground‐Motion Prediction Equations. Bulletin of the Seismological Society of America 2018;; 108 (2): 815–835. doi: https://doi.org/10.1785/0120170116 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract In this study, we use a genetic algorithm to invert horizontal ground‐motion intensity measures (GMIMs) predicted from the empirical Next Generation Attenuation‐West2 (NGA‐West2) ground‐motion prediction equations (GMPEs) to estimate a consistent and correlated set of seismological parameters to use with an equivalent point‐source stochastic model. The GMIMs are peak ground acceleration and pseudospectral acceleration evaluated over a wide range of magnitudes, distances, and frequencies. The inversion is performed for M 3.5–8.0⁠, RRUP=1–300 km⁠, T=0.01–10 s⁠, and National Earthquake Hazard Reduction Program (NEHRP) B/C site conditions. Seismological parameters are obtained as a function of earthquake magnitude. The near‐source geometric spreading was modeled as both magnitude‐ and frequency dependent to fit the empirical predictions. The agreement between the model and empirical predictions over all magnitudes and distances evaluated in this study is generally within 10%, with some local exceptions. The near‐source geometric spreading is consistent with a distance decay of R−0.8 to R−1.3 at frequencies of f≤1 Hz for M ranging from 3.5 to 8. Near 5 Hz, the distance decay is expressed as R−1.17⁠, on average at short distances. At larger frequencies, the near‐source distance decay varies from R−1.0 to R−1.25⁠. This stochastic model can be used for any application that requires a frequency‐domain representation of the NGA‐West2 GMPEs. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.