Comparison of Methods to Produce Virtual Ruptures for Background Seismicity
Description:
Virtual ruptures have become the standard of practice for modeling potential future earthquakes within source zones for probabilistic seismic hazard analyses (Bommer and Montaldo-Falero, 2020). The benefit of using virtual ruptures over point sources is the direct availability of distance metrics, such as rupture (Rrup) and Joyner-Boore (RJB) distances, needed for ground motion models (GMM). Point sources provide only epicentral (Repi) or hypocentral (Rhyp) distances, and therefore require a conversion (i.e. Scherbaum et al., 2004, EPRI, 2004, 2013, and Thompson and Worden, 2018) in most cases, which can result in an underestimation of hazard (Bommer and Akkar, 2012).
A significant challenge lies in the absence of standardized algorithms for producing virtual ruptures, with different code developers following different algorithms without any validated results as reference. The goal of this study is to start the validation and comparison process of two virtual rupture generator programs, similar to the study performed for seismic hazard programs (Hale et al., 2018). The two virtual rupture generators (VRG) within this study, referred to as VRG1 and VRG2, have different methods of placing, scaling, and assigning seismicity to the virtual ruptures. The two VRGs consist of one developed by Slate Geotechnical Consultants, Inc. and another developed by WSP Global Inc.
Multiple scenarios are run through the two VRGs and the resulting distance distributions are compared. Each scenario examines the impact of individual parameters, such as spatial distribution and rupture geometry, on the resulting distance metrics. A small number of scenario comparisons are discussed in depth as they illustrate differences in methodologies and results, as well as two scenarios that were used in a simple hazard analysis to show the sensitivity to differences in the VRGs.
Session: Assessing Seismic Hazard for Critical Facilities and Infrastructure – Insights and Challenges [Poster Session]
Type: Poster
Date: 5/3/2024
Presentation Time: 08:00 AM (local time)
Presenting Author: Micaela
Student Presenter: No
Invited Presentation:
Authors
Michael Yust myust@slategeotech.com Slate Geotechnical Consultants |
Micaela Largent Presenting Author Corresponding Author mlargent@slategeotech.com Slate Geotechnical Consultants |
Tessa Williams twilliams@slategeotech.com Slate Geotechnical Consultants |
Jennie Watson-Lamprey jwatsonlamprey@slategeotech.com Slate Geotechnical Consultants |
Valentina Montaldo-Falero valentina.montaldo@wsp.com WSP Global |
John Stamatakos john.stamatakos@swri.org Southwest Research Institute |
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Comparison of Methods to Produce Virtual Ruptures for Background Seismicity
Category
Assessing Seismic Hazard for Critical Facilities and Infrastructure – Insights and Challenges