Structural Performance of Steel Shelf Angles with Thermally Improved Detailing
Publication: Journal of Structural Engineering
Volume 146, Issue 10
Abstract
Structural elements that span the building envelope are susceptible to becoming thermal bridges, transferring heat and energy between interior and exterior. This is especially true with steel structural elements. As part of a larger effort aimed at mitigating thermal bridges in building structures, this work focuses on steel shelf angles in steel building structures, a common cladding detail. Steel shelf angles used to support masonry cladding are examples of continuous thermal bridges, because they are integrally connected to the structural system around the building perimeter. With the aim of preventing energy loss and condensation at these steel details, this work addresses the structural integrity of a range of thermal bridge mitigation strategies through combined experimental and computational research. Of particular interest is the structural performance of these steel shelf angle systems with thermally improved shims added between shelf angle and the supporting structural system using snug-tight bolts. Shim material and thickness are varied, along with angle size, bolt diameter, and bolt material. Computational results support the experimental findings that adding thermally improved shims can improve the structural performance of shelf angles under design loads. Design guidance is provided to account for these new variables and limit states.
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Data Availability Statement
All data, models, or code generated or used during the study are available from the corresponding author by request. These include raw experimental data files, derived experimental data files, code used to process the experimental data, and computational modeling files. Data, models, or code generated or used during the study relating to materials named “proprietary 1” and “proprietary 2” are proprietary or confidential in nature and may only be provided anonymized, as they are named herein.
Acknowledgments
The authors would like to thank project team members Mehdi Zarghamee, James Parker, Pedro Sifre, Sean O’Brien, Mariela Corrales, Nathalie Skaf, Elisa Livingston, and Jessica Coolbaugh of Simpson Gumpertz & Heger, Inc., Yujie Yan, Dennis Rogers, Michael MacNeil, and Kurt Braun of Northeastern University, and the members of the Industrial Advisory Panel and the ACMA-Pultrusion Industry Council Technical Advisory Team for their contributions to this project. This material is based upon work supported by the Charles Pankow Foundation, the American Institute of Steel Construction, the American Composites Manufacturers Association (ACMA), the ACMA-Pultrusion Industry Council, the National Science Foundation under Grant No. CMMI-0654176, Simpson Gumpertz & Heger, Inc., Klepper Hahn & Hyatt, and Northeastern University. In-kind support was provided by ArmadilloNV, Bedford Reinforced Plastics, Capone Iron, Creative Pultrusions, Fabreeka, Fastenal, Inframetals, and Strongwell. This support is gratefully acknowledged. Any opinions, findings, and conclusions expressed in this material are those of the authors and do not necessarily reflect the views of the sponsors.
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Published In
Journal of Structural Engineering
Volume 146 • Issue 10 • October 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: May 30, 2019
Accepted: Apr 15, 2020
Published online: Jul 28, 2020
Published in print: Oct 1, 2020
Discussion open until: Dec 28, 2020
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