SCEC Award Number 13161 View PDF
Proposal Category Collaborative Proposal (Integration and Theory)
Proposal Title Validation of earthquake simulations and their effects on tall buildings considering spectral shape and duration
Investigator(s)
Name Organization
Gregory Deierlein Stanford University Ting Lin Stanford University
Other Participants One PhD student.
SCEC Priorities 6 SCEC Groups GMSV, EEII, CME
Report Due Date 03/15/2014 Date Report Submitted N/A
Project Abstract
 The objectives of this project are to: (a) validate earthquake simulations from an engineering perspective through assessment of structural performance of tall buildings subjected to recorded and simulated ground motions; (b) examine effects of spectral shape and duration on structural response; (c) provide insights regarding the use of simulations for nonlinear dynamic analysis of tall buildings. Comparable sets of recorded and simulated motions were selected from the Pacific Earthquake Engineering Research Center (PEER) Next Generation Attenuation (NGA) database and the 2013 simulations of historical events from the Southern California Earthquake Center (SCEC) Broadband Platform (BBP), respectively. Ground motions were selected based on target scenarios defined by Conditional Spectra (CS) and significant duration. Nonlinear dynamic analyses of a 20-story concrete moment frame building were performed to examine structural responses (story drifts, floor accelerations, and story shears) at intensity levels up to collapse. Results for this structure indicated that responses to simulated and recorded ground motions were generally similar at intensity levels prior to observation of collapses; collapse capacities were also in good agreement. However, when the hysteretic energy dissipation capacity of the structure was reduced, differences in median collapse capacities (~10%) are observed between the simulated and recorded motions. Research is ongoing to examine whether there is a systematic bias in the results that can be traced back to the ground motion simulation techniques. Consideration of duration and spectral shape in ground motion selection is potentially important for tall buildings with large deterioration.
Intellectual Merit The project addresses the SCEC4 priority objective 6e “collaborate with the engineering community in validation of ground motion simulations”, and contributes to interdisciplinary focus area G “Earthquake Engineering Implementation Interface (EEII)”, specifically, simulation validation with comparisons to recorded counterparts on parameters of engineering interest for “Technical Activity Group on Ground Motion Simulation Validation”, refined intensity measures for “improved hazard representation”, implications for building code application or risk analysis for “ground motion time history simulation”, and impact of simulated long-period ground motions on tall buildings for “collaboration in structural response analysis”. Through our work, a target criterion that incorporates both Conditional Spectra and significant duration was developed and applied to select recorded and simulated ground motions for assessing tall building responses. This study has contributed to validating the use of simulated ground motions in earthquake engineering and advanced our understanding of the role of spectral shape, duration, and other ground motion characteristics on tall building collapse capacity.
Broader Impacts The project enhances communication, education and outreach through connecting SCEC scientists with earthquake engineers, and disseminating research results in the engineering community via professional conferences and academic courses. Deierlein, Lin, and Bijelić presented results of the SCEC-funded project and shared SCEC’s mission with the engineering community, including the Network for Earthquake Engineering Simulation (NSF-NEES), Applied Technology Council (ATC), Pacific Earthquake Engineering Researcher (PEER) Center, US/China tall building collaboration and industry partner meetings. Oral and poster presentations were made at the 2013 SCEC Annual Meeting and research efforts have been coordinated with the Ground Motion Simulation Validation (GMSV) Technical Activity Group (TAG). PhD student Bijelić was selected to participate at the inaugural 2013 International Summer School on Earthquake Science (iSSEs) in Japan. A Stanford conversation between earthquake scientists and engineers was initiated, via faculty and student meetings, Earth Science Day at the Blume Earthquake Engineering Center at Stanford, and joint seminars of geophysics and earthquake engineering. SCEC’s high performance computing (HPC)-facilitated simulations also became part of Lin’s curricular materials developed for Performance-Based Earthquake Engineering, an advanced graduate course at Stanford. A paper has been accepted for publication in the 10th National Earthquake Engineering Conference in Alaska, and a journal publication is in preparation.
Exemplary Figure Figure 2. Collapse fragility curves for recorded and simulated ground motion sets from(a) CS group, lambda/lambda,0 = 1.0; (b) CSDS group, lambda/lambda,0 = 1.0; (c) CS group, lambda/lambda,0 = 0.4; (d) CSDS group, lambda/lambda,0 = 0.4. theta and beta represent the median collapse capacity and dispersion, respectively.