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Project: Semiactive Control of Nonlinear Structures


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Full-Scale Experimental Verification of Semiactive Structural Control

Sponsors: This research is supported by the National Science Foundation (NSF) under grant CMS-0612661 (pre-NEES Research) and CMS-0402490 (NEES Operations) and by equipment donations from the Lord Corporation.


Overview: Semiactive structural control shows great potential for hazard mitigation in civil structures. Semiactive control provides supplemental damping to more efficiently dissipate the energy due to dynamic loads and thereby increases the safety and performance of the structure. Semiactive control has typically been designed for and applied to linear structures. Civil structures, however, are designed to yield, thus behaving nonlinearly during extreme dynamic loading. Because they cannot inject mechanical energy into the controlled system, semiactive devices are inherently stable and well suited for application to structures with aleatoric (the randomness of excitations) and epistemic (the inherent variability of structural and nonstructural components and systems) uncertainties and systems with the potential to behave nonlinearly. 

Semiactive control in the presence of nonlinear structural behavior has yet to be demonstrated experimentally. The full-scale experimental dynamic testing of a nonlinear controlled building is a challenging task that can be addressed by the NEES Fast Hybrid Test System at the University of Colorado at Boulder. 

This research examines the experimental verification of semiactive control through the use of real-time hybrid testing. These experiments will employ hybrid testing of three semiactive large-scale Magneto-Rheological (MR) fluid dampers while simulating in real-time the nonlinear response of a building structure subjected to suites of simulated and recorded earthquakes.

For more details on the MR fluid dampers, analytical studies, fast hybrid tests and opportunity to participate in the open portion of these experiments, please follow the links at the top of this page. 

Further Information:

For more information on this project, please contact:

Dr. Richard Christenson

Assistant Professor
Dept of Civil & Environmental Engineering
University of Connecticut
261 Glenbrook Road Unit 2037
Storrs, CT 06269-2037

Phone: (860) 486-2270
Fax: (860) 486-2298
Email: rchriste@engr.uconn.edu


University of Connecticut School of Engineering Department of Civil & Environmental Engineering
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