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Progress Report of the SCEC Utilization of Ground Motion Simulations (UGMS) Committee

C.B. Crouse, & Thomas H. Jordan

Published September 20, 2016, SCEC Contribution #6393, 2016 SCEC Annual Meeting Talk on 9/14 09:00 (PDF)

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The goal of the UGMS committee, since its inception in the spring of 2013, has been to develop digital long-period response spectral acceleration maps for the Los Angeles region, for inclusion in the NEHRP and ASCE 7 Seismic Provisions and in the Los Angeles City Building Code. The maps are based on 3-D numerical ground-motion simulations, generated using CyberShake, and ground motions computed using the four NGA West2 empirical ground-motion prediction equations that incorporate a basin amplification term. The UGMS developed a method to combine the response spectra from both approaches to generate risk-targeted Maximum Considered Earthquake (MCER) response spectra for the region. These response spectra cover the period band from 0 to 10 sec and will be proposed as an amendment to the ASCE -16 standard adopted by the City of Los Angeles. The MCER response spectrum at a given site would be obtained from a USGS-like web look-up tool. Users would input the site coordinates and site class (or Vs30), and the output would be a “site-specific” MCER response spectrum and associated SDS and SD1 values of the Design Response Spectrum. The user would have the option of obtaining more information, such as hazard curves, risk coefficients, and source and magnitude-distance deaggregation data. The look-up tool is currently being developed by SCEC with a scheduled release of a trial version toward the end of 2016 or early 2017.

The work of the UGMS committee has been coordinated with (1) the SCEC Ground Motion Simulation Validation Technical Activity Group (GMSV-TAG), (2) other SCEC projects, such as CyberShake and UCERF, and (3) the USGS national seismic hazard mapping project.

Key Words
CyberShake, numerical ground-motion simulations, ground-motion maps

Crouse, C., & Jordan, T. H. (2016, 09). Progress Report of the SCEC Utilization of Ground Motion Simulations (UGMS) Committee. Oral Presentation at 2016 SCEC Annual Meeting.

Related Projects & Working Groups
Earthquake Engineering Implementation Interface (EEII)