Full-Scale Tests of Gapped-Inclined Bracing System: Seismic Retrofit for Soft-Story Buildings
Publication: Journal of Structural Engineering
Volume 145, Issue 10
Abstract
This paper presents the results of full-scale experimental validations of the gapped-inclined bracing (GIB) system, a novel structural device for the seismic retrofit of soft-story buildings. The experiment consisted of three phases. Phase I tested a single brace to investigate its constructability and characterize its component-level performance. The second and third phases compared the reversed-cyclic response of two full-scale RC single-bay, single-story frames representing the soft story of a six-story RC frame: a conventional frame and the same frame retrofitted with GIBs. With the results observed from Phase I, the design considerations and constructability of the GIB system were improved for Phase III. The results of Phases II and III demonstrate that the GIB system significantly increases the lateral drift capacity of the RC frame, shifting strength degradation from for the original frame to more than drift for the retrofitted frame. In addition, even after considerable damage to the columns, the retrofitted frame was able to undergo repeated cycles of up to 7.0% drift without compromising its gravity load-bearing capacity, revealing that the damaged frame develops a stable GIB-only rocking response for large drifts.
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Acknowledgments
The Natural Sciences and Engineering Research Council of Canada, through an Ideas to Innovation grant, provided the financial support for this research. The authors would like to thank Professor Michele Calvi from the Instituto Universitario di Studi Superiori di Pavia in Italy and Professor Timothy Sullivan from the University of Canterbury in New Zealand for their thoughtful feedback on the development of the testing program presented in this paper. The authors would also like to thank the staff of the Structures Laboratory at the University of Toronto for their help with laboratory preparations.
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Published In
Journal of Structural Engineering
Volume 145 • Issue 10 • October 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Feb 5, 2018
Accepted: Jan 31, 2019
Published online: Jul 17, 2019
Published in print: Oct 1, 2019
Discussion open until: Dec 17, 2019
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