Improved Link-to-Column Connections for Steel Eccentrically Braced Frames
Publication: Journal of Structural Engineering
Volume 141, Issue 8
Abstract
Link-to-column connections in steel eccentrically braced frames must be capable of sustaining large cyclic forces and inelastic rotations. United States code provisions require that satisfactory performance of link-to-column connections be verified by testing under a prescribed loading protocol. However, there are few link-to-column connection details that have satisfied these testing criteria. This paper describes a pilot investigation of two promising link-to-column connection details, as follows: (1) the fillet welded connection, which uses fillet welds or a combination of fillet and groove welds between the link and the column flange; and (2) the supplemental web doubler connection, which reinforces the connection region using a pair of doubler plates in the first link web panel next to the column, parallel to but offset from the link web. These two details showed excellent performance in a series of eight tests. This paper describes these link-to-column connection details, summarizes the results of cyclic loading tests, and discusses design issues and approaches for these connections.
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Acknowledgments
The writers gratefully acknowledge the funding provided for this project by the AISC (Director of Research Tom Schlafly). Dr. Subash Goel, Dr. Tom Sabol, and Mr. Tom Schlafly provided valuable guidance throughout the course of the research reported in this paper. Special thanks are extended to the staff at the Phil M. Ferguson Structural Engineering Laboratory at the University of Texas at Austin for their assistance. The opinions expressed in this paper are those of the writers and do not necessarily reflect the views of the sponsors or the individuals noted in this paper.
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Published In
Journal of Structural Engineering
Volume 141 • Issue 8 • August 2015
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Oct 5, 2013
Accepted: Jan 28, 2014
Published online: Sep 18, 2014
Discussion open until: Feb 18, 2015
Published in print: Aug 1, 2015
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