ShakeOut Scenario Earthquake

Seismic Performance Analysis of Reinforced Concrete Frame Buildings due to the ShakeOut Earthquake

Abbie B. Liel^a), Kathryn P. Lynch^b), Kristen L. Rowe^b)

a) Assistant Professor- Department of Civil Environmental and Architectural Engineering, University of Colorado at Boulder

b) Graduate Researcher- Department of Civil Environmental and Architectural Engineering, University of Colorado at Boulder

Reinforced concrete (RC) frame buildings, constructed between approximately 1950 and present day, are a widespread form of office, commercial and industrial construction in Southern California. As such, they represent a major economic investment by business owners, corporations and government agencies, and support critical economic and social activities. Past earthquakes in the region, including the 1971 San Fernando (Mw = 6.6) and 1994 Northridge (Mw = 6.7) earthquakes, have caused significant damage to older, nonductile, RC frame buildings, highlighting deficiencies in design and detailing in buildings constructed before major changes to concrete seismic codes were implemented in the mid-1970s.

This study examines the impact of a major earthquake, specifically the Mw 7.8 ShakeOut scenario earthquake on the southern San Andreas fault, on older and modern RC frame buildings located in greater Los Angeles. Evaluation of building performance during the ShakeOut scenario provides predictions of building damage and collapse risk that can be used to assess the contribution of this type of structure to a community’s seismic vulnerability. These risk assessments serve to identify cities with significant collapse risk, to classify characteristics of particularly vulnerable buildings, and to compare the relative performance of older and newer RC frame buildings, providing valuable metrics for emergency planners, policy makers and building owners.

The information provided on this website describes the results for computer simulated models of 20 reinforced concrete frame structures. 12 of the building are modern ductile space and perimeter frames, ranging in height from 1 to 20 stories; the other 8 are older non-ductile space and perimeter RC frames, ranging in height from 2 to 12 stories. These computer models were analyzed using ground motions provided by SCEC and Robert Graves et. al at 745 sites along the San Andreas Fault. Results indicate collapse, maximum story drift as well as damage levels for buildings at all locations. Graphical results can be found on the GIS Images page and the full numerical results on the Results Spreadsheet page.

For more information please contact Abbie.Liel@Colorado.edu

This research was funded by the Southern California Earthquake Center and we would like to thank them for their collaboration. This data was made available for public use, please properly cite all information.

University of Colorado at Boulder
Department of Civil Environmental and Architectural Engineering
ECOT 441, UCB 428
Boulder, CO 80309
Phone: 303-492-6382