Fire Safety of Glued-Laminated Timber Beams in Bending
Publication: Journal of Structural Engineering
Volume 143, Issue 7
Abstract
Design models for timber structures with fire-resistance requirements usually take into account the loss in cross section due to charring and the temperature-dependent reduction in strength and stiffness of the residual cross section. Standards for glued timber elements like glued-laminated timber beams have assumed that structural adhesives do not influence the fire resistance, but further specifications of adequate adhesive requirements are missing. Investigations were therefore conducted to determine the influence of different adhesives on the load-carrying behavior of glued-laminated timber beams in fire. Large-scale fire-resistance tests in combination with extensive finite-element analyses showed that a modification of the zero-strength layer thickness of currently used in a standard design code should be discussed for glued-laminated timber loaded in bending in a future release of this design code. An increase of the zero-strength layer considering the finger-joint strength depending on the approved structural adhesive is not needed.
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Acknowledgments
The authors gratefully acknowledge the financial support by the Swiss Commission for Technology and Innovation (CTI) and all industrial and academic partners involved in this project.
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Published In
Journal of Structural Engineering
Volume 143 • Issue 7 • July 2017
Copyright
©2017 American Society of Civil Engineers.
History
Received: Dec 10, 2015
Accepted: Dec 20, 2016
Published online: Mar 10, 2017
Published in print: Jul 1, 2017
Discussion open until: Aug 10, 2017
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