RHS-to-RHS Zero-Gap K-Connections
Publication: Journal of Structural Engineering
Volume 148, Issue 6
Abstract
The design of a rectangular hollow-section K-connection in which the branches are welded toe-to-toe to the chord is not permitted at present in design guides and codes. To illustrate the feasibility of such connections, two full-scale cold-formed welded rectangular hollow-section K-connection laboratory tests, including one control specimen and one zero-gap specimen, are presented. A new chord face shear analytical model based on a yield-line mechanism is proposed for such connections, and its validity was evaluated against the experiments. Nonlinear finite-element connection models were built and validated against the laboratory tests, and a numerical parametric study was performed on similar connections with a broader range of parameters. From the results of the finite-element study, an empirical connection strength model was also generated by regression curve-fitting. Based on the experimental and numerical data, the proposed chord face shear analytical model is recommended for design of rectangular hollow-section zero-gap K-connections. The gap size can also be increased up to the summation of the two branch thicknesses.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
Financial support for this project was provided by the American Institute of Steel Construction (AISC), the Steel Tube Institute (STI), the American Iron and Steel Institute (AISI), and the Natural Sciences and Engineering Research Council of Canada (NSERC). Atlas Tube (Harrow, Ontario, Canada) donated hollow structural sections for the laboratory test specimens.
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Published In
Journal of Structural Engineering
Volume 148 • Issue 6 • June 2022
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Oct 22, 2021
Accepted: Jan 24, 2022
Published online: Mar 30, 2022
Published in print: Jun 1, 2022
Discussion open until: Aug 30, 2022
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