2026 SCEC GM-SVU TAG Workshop 1

Date: October 29, 2026
Location: Ronald Tutor Hall 526, University of Southern California, Los Angeles, CA
Workshop Organizers: Sanaz Rezaeian (USGS), Scott Callaghan (USC), Farzin Zareian (UCI), Buka Nweke (USC), Maha Kenawy (Oklahoma State)
SCEC Award: 26089

This workshop is invitation only.
Contact the organizers for more information.

Summary

Simulated earthquake ground motions can support nonlinear response history analysis (RHA) and probabilistic seismic hazard analysis (PSHA), but their effective and responsible use depends on readily accessible simulation databases that include model information and uncertainty documentation, as well as validation evidence and guidelines to select simulations appropriate for the intended application.

The new SCEC Ground Motion Simulation, Validation, and Utilization (GM-SVU) Technical Activity Group (TAG) builds on more than a decade of research demonstrating that validation is application-specific and benefits from iterative collaboration among simulation modelers, research engineers, and hazard analysts. Through a broader effort focused on simulation selection, validation, utilization, and iterative improvement, the new GM-SVU TAG aims to address the gaps identified by previous researchers and the community as obstacles to further advancing the use of simulations in practice. The goal of the TAG is to curate an initial documented simulation dataset, provide validation evidence, and utilize it in example applications; concurrently, the TAG aims to develop guidelines for both RHA and PSHA applications using this initial dataset and examples; finally, the TAG will establish pathways for the example dataset’s iterative evaluation and refinement. The longer-term goal is to develop trusted, application-ready simulation resources accompanied by practical guidance for both RHA and PSHA applications.

Two focused working meetings (Workshop 1 on October 29, 2026, and Workshop 2 on January 21, 2027) are planned in the first year of this TAG’s efforts to achieve the above goals from curating an initial dataset, using them in example applications, drafting guidelines for their use, and collecting community feedback on this process. Plans for finalizing the guidelines and establishing pathways for iterative evaluation and refinement of simulations for future application-ready simulation resources will be the focus of the TAG after these two workshops.

Workshop 1 will bring together participants with relevant expertise to review earlier validation research and SCEC simulation capabilities, assess the proposed initial dataset, and refine plans for example use studies. Participants will also review a framework for the RHA and PSHA utilization guidelines. Plans for example use studies include RHA of a building and a bridge for code-based design and reviewing available literature and tools on simulation needs for PSHA applications. Workshop 1 will conclude by identifying needed revisions, responsibilities, and next steps required before convening for Workshop 2, when results of the use studies and a draft of the guidelines will be shared. Although the meeting is intentionally focused, the datasets, application examples, and guidance advanced through this work are intended to benefit the broader earthquake science and engineering communities.

Workshop 1 Goals

The workshop will establish a shared foundation for the GM-SVU TAG’s Year 1 work and refine plans for the initial simulation dataset, nonlinear RHA example use studies, and development of guidelines for use of simulations in PSHA and RHA applications. Specific objectives include:

Establish a shared foundation for the Year 1 work. Review lessons from the previous ground motion simulation validation (GMSV) efforts, community feedback, and current and emerging SCEC simulation capabilities to identify the research priorities and validation questions most relevant to PSHA and RHA applications.
Review the plan for the initial simulation dataset. Present the proposed CyberShake simulations, supporting information, and validation evidence, and gather feedback on whether they meet the needs of the planned RHA example use studies and needs of the PSHA community before the dataset is finalized and distributed.
Refine the proposed RHA application exercises. Review existing research, present the building and bridge teams’ simulation needs and analysis plans, and gather feedback on the proposed simulation dataset, validation metrics, structural demands, and other considerations.
Discuss the needs of the PSHA community. Review existing simulation-based PSHA tools and recent literature on the simulation needs of the PSHA community. Discuss the proposed guidelines and gather feedback on its development.

Participation

The workshop will bring together simulation developers, research engineers, hazard analysts, structural and geotechnical engineers, and others with expertise relevant to nonlinear RHA and PSHA applications.

Because the workshop is structured as a collaborative working meeting, in-person participation is limited to approximately 25 invited participants whose expertise can help refine the initial dataset and application plans. Participants are strongly encouraged to attend in person for the full day so they can follow the progression of discussions and contribute fully to the workshop plans and next steps. Refreshments and meals will be provided as noted on the agenda.

Remote participation will be available for invited participants who cannot travel and for others whose interests or expertise align with the workshop goals. Those interested in participating remotely should contact the workshop organizers.

Travel Information

The workshop will be held in Ronald Tutor Hall (RTH), Room 526 on the University of Southern California’s University Park Campus, 3710 McClintock Ave, Los Angeles, CA 90089. Los Angeles International Airport (LAX) and Hollywood Burbank Airport (BUR) provide convenient air access to the Los Angeles area. Rideshare, taxi, rental-car, and public-transit options are available throughout the region.

Participants driving to USC will be emailed a pass code to park for the day at the Downey Street Parking Structure, which is located at Vermont Ave and Downey Way—immediately northwest of RTH. Lodging will be provided for invited participants at the Vagabond Inn, which is a 20-minute walk across campus to RTH or a 12-minute trip on the “F” Dash bus with a $0.50 cash fare.

SCEC Technical Activity Group

GM-SVU TAG Co-PIs & Organizers: Sanaz Rezaeian (USGS), Scott Callaghan (SCEC), Buka Nweke (USC), Maha Kenawy (OK State), Farzin Zareian (UCI), Nico Luco (USGS), Ahmed Elbanna (SCEC), Tran Huynh (SCEC), Brad Aagaard (USGS)

GM-SVU TAG Members: Albert Kottke (PG&E), Arben Pitarka (LLNL), Artie Rodgers (LLNL), Audrey Dunham (USGS), Brendon Bradley (U of Canterbury), Camilo Pinilla-Ramos (GFZ Potsdam), Claire Doody (LLNL), Elham Shokrgozar (U of Wyoming), Erin Wirth (USGS), Evan Hirakawa (USGS), Fabio Silva (SCEC), Felipe Kuncar (U of Canterbury), Greg Deierlein (Stanford), Jeffrey Bayless (AECOM), Jonathan Stewart (UCLA), Kevin Milner (USGS), Kim Olsen (SDSU), Kyle Withers (USGS), Morgan Moschetti (USGS), Norman Abrahamson (UC Berkeley), Pengfei Wang (Old Dominion University), Rie Nakata (LBNL), Robert Graves (USGS), Xiaofeng Meng (SCEC), Yongfei Wang (Verisk)

October 29, 2026

All times below Pacific Standard Time (UTC -7)

Time	Agenda Item	Presenter
08:30 - 09:00	Workshop Check-In with Continental Breakfast
09:00 - 09:15	Welcome and SCEC GM-SVU TAG Overview Introduction to the GM-SVU TAG, Workshop 1 goals, and expected contributions to the Year 1 work.	Sanaz Rezaeian
09:15 - 10:30	Session 1: From GMSV Lessons to Utilization Guidance Guided discussions reviewing lessons from earlier GMSV research and community feedback. Discuss potential applications of simulated ground motions and the outline of the proposed guidelines. Consider COSMOS’s ongoing efforts in developing international standards for disseminating simulated motions.	Moderator: Sanaz Rezaeian Reporter: Brad Aagaard
09:15 - 09:30	Lessons from the GMSV Synthesis Paper	Sanaz Rezaeian
09:30 - 09:45	Community Survey Findings	Sanaz Rezaeian
09:45 - 10:00	COSMOS International Standards	Brad Aagaard
10:00 - 10:30	Community Discussion: What should be included in the proposed “Guidelines on Utilization of Ground Motion Simulations” to address the information engineers will need?	All
	References Rezaeian, S., Stewart, J. P., Luco, N., & Goulet, C. A. (2024). Findings from a decade of ground motion simulation validation research and a path forward. Earthquake Spectra, 40(1), 346-378. https://doi.org/10.1177/87552930231212475. SCEC Contribution 15034. Aagaard, B., Askan, A., & Rezaeian, S. (2026). Developing International Standards and Guidelines for Validating, Disseminating, and Utilizing Simulated Earthquake Ground Motions. Presentation at 2026 SCEC/USGS GM-SVU Workshop. See Slides.
10:30 - 10:45	Break
10:45 - 12:00	Session 2: SCEC Simulation Resources & Initial CyberShake Dataset Presentations and discussion reviewing SCEC’s current and emerging simulation capabilities, validation resources, and proposed initial dataset for PSHA and nonlinear RHA studies.	Moderator: Scott Callaghan Reporter: Edric Pauk
10:45 - 11:00	Current SCEC Resources: CyberShake, Broadband Platform, and GMSV Toolkit	Scott Callaghan
11:00 - 11:15	Overview of Initial Southern California Dataset	Scott Callaghan
11:15 - 11:30	Emerging Simulation Capabilities: Northern California, updated ERFs, and AI-Aided Approaches	Ahmed Elbanna
11:30 - 12:00	Community Discussion: What simulations, supporting information, and validation evidence should the initial dataset include?	All
	References Callaghan, S. (2026, 08). SCEC’s Physics-Based Seismic Hazard Modeling Platforms. Oral Presentation at 2026 SCEC Annual Meeting. SCEC Contribution 15653. Callaghan S. (2025). CyberShake Study 22.12, SCECpedia, available at https://strike.scec.org/scecpedia/CyberShake_Study_22.12. Silva, F., Goulet, C. A., Maechling, P. J., & Ben-Zion, Y. (2023, 09). The SCEC GMSV Toolkit: Open-Source Tools for Ground Motion Simulation Processing and Validation. Poster Presentation at 2023 SCEC Annual Meeting. SCEC Contribution 12787.
12:00 - 13:15	Lunch
13:15 - 14:45	Session 3: Using Simulated Ground Motions in Nonlinear RHA Presentations and discussion reviewing current code provisions, lessons from earlier structural applications, and proposed building and bridge analysis workflows to identify simulation needs for nonlinear RHA.	Moderator: Maha Kenawy Reporter: Melisa Herrera
13:15 - 13:35	Building Code Provisions for Using Simulated Ground Motions & Lessons from Previous Building Response Analyses	Nico Luco / Farzin Zareian
13:35 - 13:55	Proposed Plan and Simulation Needs for Building RHA	Maha Kenawy
13:55 - 14:15	Proposed Plan and Simulation Needs for Bridge RHA	Farzin Zareian
14:15 - 14:45	Community Discussion: What should the scope of the proposed RHA guidelines be as related to simulation database, selection criteria, validation evidence, etc.?	All
	References Baker, J. W., Rezaeian, S., Goulet, C. A., Luco, N., & Teng, G. (2021). A Subset of CyberShake Ground Motion Time Series for Response History Analysis. Earthquake Spectra, 37(2), 1162-1176. https://doi.org/10.1177/8755293020981970. SCEC Contribution 10077. Kenawy M. & Pitarka, A. (2025). Performance assessment of near-fault buildings subjected to physics-based simulated earthquake ground motions with fling step, Earthquake Spectra, 41(1), 381-411. https://doi.org/10.1177/87552930241285022. SCEC Contribution 15681. Kenawy, M., McCallen, D. B., & Pitarka, A. (2021). Variability of near‐fault seismic risk to reinforced concrete buildings based on high‐resolution physics‐based ground motion simulations. Earthquake Engineering & Structural Dynamics, 50(6), 1713-1733. https://doi.org/10.1002/eqe.3413. SCEC Contribution 11018. Kenawy, M., McCallen, D. B., & Pitarka, A. (2023). Characteristics and selection of near-fault simulated earthquake ground motions for nonlinear analysis of buildings. Earthquake Spectra, 39(4), 2281-2322. https://doi.org/10.1177/87552930231182164. SCEC Contribution 15683. Fayaz, J., Azar, S., Dabaghi, M., & Zareian, F. (2020). Methodology for Validation of Simulated Ground Motions for Seismic Response Assessment: Application to CyberShake Source-Based Ground Motions. Bulletin of the Seismological Society of America, 111(1), 226-241. https://doi.org/10.1785/0120200240. SCEC Contribution 15694. Fayaz, J., Dabaghi, M., & Zareian, F. (2020). Utilization of Site-Based Simulated Ground Motions for Hazard-Targeted Seismic Demand Estimation: Application for Ordinary Bridges in Southern California. Journal of Bridge Engineering, 25(11). https://doi.org/10.1061/(ASCE)BE.1943-5592.0001634. SCEC Contribution 15695.
14:45 - 15:00	Break
15:00 - 16:30	Session 4: Using Simulated Ground Motions in PSHA Presentations on how simulations can be incorporated into the USGS NSHMs (from guiding basin amplifications in the past (2023) NSHM to fully simulation-based NSHMs in the future) and other hazard applications such as the SCEC UGMS Tool for determining MCE_R design spectrum, and discussion on simulation requirements for PSHA applications.	Moderator: Buka Nweke Reporter: Xiaofeng Meng
15:00 - 15:20	Simulations in National Seismic Hazard Models	Kyle Withers
15:20 - 15:40	The Utilization of Ground Motion Simulations (UGMS) Tool & Upcoming Updates	Edric Pauk / Xiaofeng Meng
15:40 - 16:00	What Does PSHA Need from Simulations?	Buka Nweke
16:00 - 16:30	Community Discussion: What should the scope of the proposed PSHA guidelines be as related to simulation applicability and improvements for advancing their use?	All
	References Liou, I. Y., Cotton, F., Weatherill, G., & Abrahamson, N. A. (2026). Advancing the Use of Simulated Ground Motions in Physics-Based Probabilistic Seismic Hazard Analysis From Research to Practice. Bulletin of the Seismological Society of America, (under review). SCEC Contribution 15685. KC, S., Nweke, C. C., & Graves, R. W. (2026). Assessing bias and variability in physics‐based ground‐motion simulations for moderate‐magnitude earthquakes in Southern California. Bulletin of the Seismological Society of America, 116(5), 2110-2132. https://doi.org/10.1785/0120260051. SCEC Contribution 15667. Crouse, C., Jordan, T. H., Milner, K. R., Goulet, C. A., Callaghan, S., & Graves, R. W. (2018, 06). Site-Specific MCER Response Spectra for Los Angeles Region based on 3-D Numerical Simulations and the NGA West2 Equations. Oral Presentation at 11th National Conference in Earthquake Engineering. Paper #518. SCEC Contribution 8024. Pauk, E. (2026). Meeting the Need for Site-Specific, Long-Period MCER Response Spectra: The SCEC UGMS Tool for LA. Presentation at 2026 SCEC/USGS GM-SVU Workshop. See Slides. Moschetti, M., Thompson, E., & Withers, K. (2024). Basin effects from 3D simulated ground motions in the Greater Los Angeles region for use in seismic hazard analyses. Earthquake Spectra, 40(2), 1042-1065. https://doi.org/10.1177/87552930241232372. SCEC Contribution15691. Moschetti, M., Aagaard, B., Ahdi, S., Altekruse, J., Boyd, O., Frankel, A., Herrick, J., Petersen, M., Powers, P., Rezaeian, S., Shumway, A., Smith, J., Stephenson, W., Thompson, E., & Withers, K. (2024). The 2023 US National Seismic Hazard Model: Ground‐motion characterization for the conterminous United States. Earthquake Spectra, 40(2), 1158-1190. https://doi.org/10.1177/87552930231223995. SCEC Contribution 15693.
16:30 - 16:59	Summary & Next-Steps Review key feedback on the initial CyberShake dataset, application studies, and proposed guidelines, and confirm responsibilities and next steps before Workshop 2.	Moderator: Sanaz Rezaeian Reporter: Farzin Zareian
17:00	Workshop Adjourns

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