Reduced-Order Modeling of Composite Floor Slabs in Fire. I: Heat-Transfer Analysis
Publication: Journal of Structural Engineering
Volume 146, Issue 6
Abstract
This paper presents a reduced-order numerical modeling approach for the analysis of heat transfer in composite floor slabs with profiled steel decking exposed to fire effects. This approach represents the thick and thin portions of a composite slab with alternating strips of shell elements, using a layered thick-shell formulation that accounts for both in-plane and through-thickness heat transfer. To account for the tapered profile of the ribs, layered shell elements representing the thick portion of the slab adopt a linear reduction in the density of concrete within the depth in the rib. The specific heat of concrete in the rib is also proportionally reduced to indirectly consider the heat input through the web of the decking, because the reduced-order model considers thermal loading only on the upper and lower flanges of the decking. The optimal ratio of modified and actual specific heat of concrete in the rib is determined, depending on the ratio of the height of the upper continuous portion to the height of the rib. The reduced-order modeling approach is validated against experimental results.
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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
Disclaimer
Certain commercial entities, equipment, products, or materials are identified in this document in order to describe a procedure or concept adequately. Such identification is not intended to imply recommendation, endorsement, or implication that the entities, products, materials, or equipment are necessarily the best available for the purpose. The policy of the National Institute of Standards and Technology is to include statements of uncertainty with all NIST measurements. In this document, however, measurements of authors outside of NIST are presented, for which uncertainties were not reported and are unknown.
References
CEN (European Committee for Standardization). 2005. Eurocode 4: Design of composite steel and concrete structures: Part 1.1: General rules, Structural fire design,. Brussels, Belgium: CEN.
Elghazouli, A. Y., and B. A. Izzuddin. 2000. “Response of idealised composite beam-slab systems under fire conditions.” J. Constr. Steel Res. 56 (3): 199–224. https://doi.org/10.1016/S0143-974X(00)00006-7.
Guo, S. 2012. “Experimental and numerical study on restrained composite slab during heating and cooling.” J. Constr. Steel Res. 69 (1): 95–105. https://doi.org/10.1016/j.jcsr.2011.08.009.
Hamerlinck, R., L. Twilt, and J. Stark. 1990. “A numerical model for fire-exposed composite steel/concrete slabs.” In Proc., 10th Int. Specialty Conf. on Cold-formed Steel Structures, 115–130. Columbia, MO: Univ. of Missouri.
Huang, Z., I. W. Burgess, and R. J. Plank. 2000. “Effective stiffness modelling of composite concrete slabs in fire.” Eng. Struct. 22 (9): 1133–1144. https://doi.org/10.1016/S0141-0296(99)00062-0.
ISO. 2014. Fire-resistance tests–Elements of building construction, ISO 834-11. Geneva: ISO.
Izzuddin, B. A., X. Y. Tao, and A. Y. Elghazouli. 2004. “Realistic modelling of composite and R/C floor slabs under extreme loading—Part I: Analytical method.” J. Struct. Eng. 130 (12): 1972–1984. https://doi.org/10.1061/(ASCE)0733-9445(2004)130:12(1972).
Jiang J., J. A. Main, F. Sadek, and J. M. Weigand. 2017. Numerical modeling and analysis of heat transfer in composite slabs with profiled steel decking. Gaithersburg, MD: National Institute of Standards and Technology.
Jiang, J., J. A. Main, J. M. Weigand, and F. Sadek. 2020. “Reduced-order modeling of composite floor slabs in fire. II: Thermal-structural analysis.” J. Struct. Eng. 146 (6): 04020081. https://doi.org/10.1061/(ASCE)ST.1943-541X.0002607.
Kwasniewski, L. 2010. “Nonlinear dynamic simulations of progressive collapse for a multistory building.” Eng. Struct. 32 (5): 1223–1235. https://doi.org/10.1016/j.engstruct.2009.12.048.
Lamont, S., A. S. Usmani, and M. Gillie. 2004. “Behaviour of a small composite steel frame structure in a “long-cool” and a “short-hot” fire.” Fire Saf. J. 39 (5): 327–357. https://doi.org/10.1016/j.firesaf.2004.01.002.
Lim L. C. S. 2003. “Membrane action in fire exposed concrete floor systems.” Ph.D. dissertation, Dept. of Civil and Natural Resources Engineering, Univ. of Canterbury.
Lim, L. C. S., A. Buchanan, P. Moss, and J. M. Franssen. 2004. “Numerical modelling of two-way reinforced concrete slabs in fire.” Eng. Struct. 26 (8): 1081–1091. https://doi.org/10.1016/j.engstruct.2004.03.009.
Main, J. A. 2014. “Composite floor systems under column loss: Collapse resistance and tie force requirements.” J. Struct. Eng. 140 (8): A4014003. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000952.
Pantousa, D., and E. Mistakidis. 2013. “Advanced modelling of composite slabs with thin-walled steel sheeting submitted to fire.” Fire Technol. 49 (2): 293–327. https://doi.org/10.1007/s10694-012-0265-x.
Sanad, A. M., S. Lamont, A. S. Usmani, and J. M. Rotter. 2000a. “Structural behaviour in a fire compartment under different heating regimes—Part 1 (slab thermal gradients).” Fire Saf. J. 35 (2): 99–116. https://doi.org/10.1016/S0379-7112(00)00024-2.
Sanad, A. M., S. Lamont, A. S. Usmani, and J. M. Rotter. 2000b. “Structural behaviour in a fire compartment under different heating regimes—Part 2 (slab mean temperatures).” Fire Saf. J. 35 (2): 117–130. https://doi.org/10.1016/S0379-7112(00)00025-4.
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©2020 American Society of Civil Engineers.
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Received: Apr 24, 2019
Accepted: Nov 18, 2019
Published online: Mar 19, 2020
Published in print: Jun 1, 2020
Discussion open until: Aug 19, 2020
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