NEESR-SD: Framework for Development of Hybrid Simulation in an Earthquake Impact Assessment Context

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

This award is an outcome of the National Science Foundation 07-506 program solicitation "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research" competition. The objective of this project is to develop an earthquake impact assessment framework that integrates hybrid simulation with free-field and structure sensor measurements, system identification-based model updating technology, probabilistic fragility analysis, and existing earthquake loss assessment software. Earthquake impact assessment is the basis for post-earthquake emergency response and recovery planning. A pilot implementation of the earthquake impact assessment framework will be conducted using the instrumented Bill E. Emerson Memorial Bridge located in Cape Girardeau, Missouri. Algorithms will be developed or adapted and communication protocols formulated to link sensor measurements directly into the hybrid system. Free field measurements will be used to characterize the hazard at the site and define strong motion records, and the structural sensors used to tune the bridge-foundation-soil model. Hybrid simulations will be undertaken using the model and input motion, while changing the design of one or more (up to three) of the supporting piers. The response of the bridge, with variation of the ground motion and pier response, will be used to derive fragility relationships which, with the hazard, will be used to estimate earthquake impact. In this manner, the relatively mature subdisciplines responsible for developing the above components will be tested in an integrated manner to assess and mitigate earthquake losses. This project will utilize the one-fifth scale loading and boundary condition boxes at the NEES equipment site at the University of Illinois at Urbana-Champaign, and leverage significant resources through other projects funded by the Missouri Department of Transportation, Federal Emergency Management Agency, Federal Highway Administration, and Mid-America Earthquake Center headquartered at the University of Illinois at Urbana-Champaign. This project will provide a stimulus to seismologists, geotechnical and structural earthquake engineers, and structural control and impact assessment experts to improve current algorithms to produce more reliable assessment of losses that underpin seismic mitigation, response, and recovery planning. The source code for the framework and the graphical user interface will be archived in NEESforge (the NEES software repository available at http://www.nees.org) and will include an example application to the Cape Girardeau Bridge. In addition, data from this project will be made publicly available through the NEES data repository (http://www.nees.org).