Experimental Testing and Numerical Simulation of Timber-Concrete Composite Floors in Fire
Publication: Journal of Structural Engineering
Volume 149, Issue 11
Abstract
Timber–concrete composite (TCC) floors exposed to fire experience charring and thermal degradation of timber, leading to a reduction in load-carrying capacity. Finite element (FE) modeling supplements data from experimental fire testing and allows for fast and economical investigation of additional design parameters. This research presents fire test results of three large-scale TCC floor specimens and development of an FE modeling methodology for TCC floors in a fire. TCC floors constructed with nail-laminated timber, cross-laminated timber, or mass ply panel, with truss plates or angled screws as shear connectors, are loaded with a uniformly distributed service-level live load and exposed to the ASTM E119-20 standard fire curve. A 2D FE modeling methodology is presented and benchmarked against the test data. The methodology integrates sequentially coupled thermal-structural analyses, which make use of temperature-dependent thermal and mechanical properties of timber and concrete. The deflection and failure times of the FE models are benchmarked against test data. Connector forces from FE models show that shear connectors remain elastic throughout the fire exposure. FE results indicate that the load-carrying capacity is dependent on tensile stress redistribution to the uncharred timber section. The FE modeling methodology effectively calculates the mechanical and fire behavior of TCC floors and highlights limits of the applicability of analytical design methods.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
This work was sponsored by the USDA Agricultural Research Service, Grant no. 58-0204-6-002.
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Published In
Journal of Structural Engineering
Volume 149 • Issue 11 • November 2023
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Mar 15, 2023
Accepted: Jun 27, 2023
Published online: Aug 31, 2023
Published in print: Nov 1, 2023
Discussion open until: Jan 31, 2024
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