Testing Protocol for Short Links in Eccentrically Braced Frames
Publication: Journal of Structural Engineering
Volume 132, Issue 8
Abstract
The inelastic rotation capacity of links in eccentrically braced frames (EBFs) is dependent on testing loading history or sequence. Current design rotations for links are based on experiments from the 1980s performed with somewhat arbitrary loading protocols. An AISC link loading protocol, derived from the standard moment frame loading protocol, has been used for link testing since 2002. This protocol results in lower link rotation capacities. Since no previous or current link protocols are based on EBF analyses, nonlinear time-history analyses were conducted to investigate cumulative rotation demands for links in EBFs. Results indicate the AISC link loading protocol is overly conservative, having 1.5 times the cumulative rotation demand and a much higher percentage of large cycles than is justifiable. A rational loading protocol for future link testing was developed based on cumulative and maximum link rotation demands observed from the time-history analyses. Experimental tests performed in a parallel study with this new protocol indicate that link design rotation capacities in the AISC Seismic Provisions are satisfactory.
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Acknowledgments
The American Institute of Steel Construction provided funding for this research; Mr. Tom Schlafly was the project manager. Mr. James Malley and the AISC Solutions Center developed designs for the prototype structures. Professor Helmut Krawlinkler provided guidance and insight in the selection of ground motions. Professors Michael Engelhardt, Subhash Goel, and Dr. Tom Sabol also provided helpful input on the project. Test data presented in Fig. 3 was provided by Professor Engelhardt.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 132 • Issue 8 • August 2006
Pages: 1183 - 1191
Copyright
© 2006 ASCE.
History
Received: Jan 8, 2004
Accepted: Oct 17, 2005
Published online: Aug 1, 2006
Published in print: Aug 2006
Notes
Note. Associate Editor: Brian Uy
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