SCEC Award Number 14002 View PDF
Proposal Category Individual Proposal (Integration and Theory)
Proposal Title Proxy metrics for ground motion simulation validation: fling parameters
Name Organization
Jack Baker Stanford University
Other Participants Lynne Burks
SCEC Priorities 6e SCEC Groups EEII, GMSV, GMP
Report Due Date 03/15/2015 Date Report Submitted N/A
Project Abstract
In this study, we identified data sources for static fling in ground motions, compiled a dataset of ground motions containing fling, extracted fling parameters from these ground motions, and derived a predictive model for fling period and amplitude that is compared to existing models. We found that ground motion simulations provided a rich and reliable data source for fling step, indicating an additional engineering use case for simulations. The work also validated the ability of simulations (specifically those of Aagard in this study) to predict fling in conditions not well captured by empirical data sources.
Intellectual Merit This work has investigated and demonstrated the validity of another dimension of ground motion simulations—namely the ability of simulations to capture the static and dynamic effects of fling in earthquakes. This is a property that is poorly constrained by empirical data sources such as strong motion accelerograms or high-rate GPS, and so provides unique information for engineering applications sensitive to static offsets during potential future earthquakes. Our technique for rapidly extracting fling step from millions of simulated time histories is novel, and our efforts to validate the extracted features versus empirical data also provided new insights in this area.
Broader Impacts This project provided partial financial support for PhD student Lynne Burks to finish her degree, and to travel to the 2014 SCEC annual meeting to present her research. The findings from the work have been cited in discussions of the ASCE 7 building code Provisions Update Committee, where there were concerns raised about the potential effects of static offsets on structures, and whether current analysis procedures were sufficient to assess these effects. The work has thus had some impact on the procedures that will be used to design future buildings in the United States.
Exemplary Figure Figure 3: Comparisons of fling displacement amplitudes from simulations, recordings, and predictive models. The smoothed average of fling amplitude for each scenario is compared to relevant empirical models and results from recordings. Each “single scenario” line represents the average fling amplitude of all simulated ground motions in one earthquake scenario as a function of closest distance to the fault. We also compare the average and maximum surface displacement along the fault for each scenario to empirical models.