Elevated Temperature Effects on Performance of a Cross-Laminated Timber Floor-to-Wall Bracket Connections
Publication: Journal of Structural Engineering
Volume 146, Issue 9
Abstract
Connections in mass timber structural systems transfer lateral forces from mass timber elements such as shear walls to floor diaphragms. Cross-laminated timber (CLT) is a prominent engineered mass timber material used to manufacture walls and floor assemblies. Fire performance research of CLT walls and floors has been abundant in recent years in an effort to develop an understanding of the performance of structural members under fire. Some fire-protected structural elements, including connections, may not be directly exposed to flames in a fire event but will experience elevated temperatures. There is limited research on elevated temperature performance of CLT connections, and consequently a lack of understanding of their fire performance in CLT structures. To aid in bridging this knowledge gap, in this study a series of cyclic shear tests were conducted on a CLT wall-to-floor bracket connection assembly to characterize thermal degradation according to a matrix of 28 exposure duration–temperature combinations. Two different methods were employed to develop force-displacement backbone models from the experimental hysteresis data. Models from both methods indicate an overall degradation of the connection performance in terms of load carrying capacity, elastic stiffness, ductility, and energy dissipation with increasing exposure to elevated temperatures.
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Data Availability Statement
Data, models, or code generated or used during the study are available from the corresponding author by request. This includes raw data, MATLAB scripts for data processing, processed spreadsheets, scripts for developing the SAWS and ASCE 41-13 models, and photographs.
Acknowledgments
The authors extend their acknowledgements to the USDA Agriculture Research Service for providing funding for this research. We would also like to acknowledge Dr. Omar Amini and Dr. John van de Lindt from Colorado State University for sharing the specifications for the connection used in this research. Lastly, we would like to thank those members of faculty, graduate students, and undergraduate workers at Oregon State University who provided input and assistance throughout the experimental testing, data analysis, and modeling processes.
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Published In
Journal of Structural Engineering
Volume 146 • Issue 9 • September 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Sep 16, 2019
Accepted: Mar 5, 2020
Published online: Jun 22, 2020
Published in print: Sep 1, 2020
Discussion open until: Nov 22, 2020
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