Fundamental Behavior of Timber Concrete-Composite Floors in Fire
Publication: Journal of Structural Engineering
Volume 147, Issue 2
Abstract
Timber-concrete composite (TCC) floors are becoming more commonly used in mass timber construction due to their increased stiffness and strength relative to nonconcrete composite timber floors. Current building codes do not recognize the contribution of the composite action of TCC floors to their combined strength and fire performance. Extensive structural testing is required for structural engineers to design fire protection in timber buildings that use TCC floors using either alternate means and methods or structural fire engineering. This paper presents two experimental studies conducted to examine (1) properties of shear connection systems used in TCC floors through ambient temperature direct shear tests, and (2) the behavior of TCC floors through large-scale fire tests performed at the National Research Council (NRC) in Canada. The main objective of this research is to collect data on the fundamental behavior of TCC floors in a fire. The results indicate that TCC floors have improved fire performance when compared with mass timber floors. In addition, the research quantifies the force-slip behavior of the shear connectors used and benchmarks the flexural behavior of TCC floors at ambient and elevated temperatures to existing analytical models.
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Data Availability Statement
All of the data and models generated or used during the study appear in the published article.
Acknowledgments
This work is in collaboration with many industry partners that are actively working on mass timber buildings. The authors thank Holmes Structures, Skidmore Owings & Merrill, Katerra, Arup, Forest Products Laboratory, and WoodWorks for their participation on technical advisory committees. The TallWood Design Institute funded the research presented in this paper through the US Department of Agriculture, Award No. 58-0204-6-002.
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Published In
Journal of Structural Engineering
Volume 147 • Issue 2 • February 2021
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Dec 19, 2019
Accepted: Aug 23, 2020
Published online: Dec 3, 2020
Published in print: Feb 1, 2021
Discussion open until: May 3, 2021
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