Characterizing the Performance of Adhesive Used in Glued-In Rod Timber Connections at Elevated Temperatures
Publication: Journal of Performance of Constructed Facilities
Volume 37, Issue 4
Abstract
A glued-in rod, which combines timber, a metal rod, and structural adhesive, is a type of connection whose fire performance is complicated to define since the rod depends on the adhesive’s thermomechanical properties. The objective of this study was to characterize the fire performance of adhesives used in glued-in rods. A total of five structural adhesives were tested: three epoxies and two polyurethanes. The tests performed consisted of applying an axial load to the glued-in rods after heating the connection to a target temperature. Load-slip curves were generated for each sample to determine their behavior at different temperatures. The results show that a reduction of up to 70% can occur in the initial stiffness of the glued-in rod when the temperature at the bond line exceeds the glass transition temperature of the adhesive determined by a dynamic mechanical analysis. This research helps to determine the guidelines for the fire design of glued-in rods and related testing and ultimately leading to a design method for providing fire-resistance to connections made of glued-in rods.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
Acknowledgments
The authors are grateful to Natural Sciences and Engineering Research Council of Canada for the financial support through its IRC and CRD programs (IRCPJ 461745-18 and RDCPJ 514294-17) as well as the industrial partners of the NSERC industrial chair on eco-responsible wood construction (CIRCERB), the industrial partners of the industrialized construction initiative, and the Créneau Accord Bois Chaudière-Appalaches. We are also thankful to the adhesive suppliers for providing technical information and specimens.
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Published In
Journal of Performance of Constructed Facilities
Volume 37 • Issue 4 • August 2023
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Nov 12, 2022
Accepted: Mar 31, 2023
Published online: Jun 5, 2023
Published in print: Aug 1, 2023
Discussion open until: Nov 5, 2023
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