Failure Assessment of Lightly Reinforced Floor Slabs. II: Analytical Studies
This article is a reply.
VIEW THE ORIGINAL ARTICLEPublication: Journal of Structural Engineering
Volume 137, Issue 9
Abstract
This paper describes numerical and analytical assessments of the ultimate response of floor slabs. Simplified analytical models and finite-element simulations are described and validated against the experimental results presented in the companion paper. The simplified analytical model accounts for membrane action and the underlying mechanisms related to failure of floor slabs by either reinforcement rupture or compressive crushing of the concrete. In this respect, the significant influence of material properties, including bond strength, is considered in the model and described in detail. A detailed nonlinear finite-element model is also employed to provide further verification of the simplified approach and to facilitate further understanding of the overall response. The results and observations of this study offer an insight into the key factors that govern the ultimate behavior. Finally, the models are applied under elevated temperature conditions to demonstrate their general applicability and reliability.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The funding provided by the UK Engineering and Physical Sciences Research Council (EPSRC) under Grant No. EPSRC-GBEP/C511204 for the work described in this paper is gratefully acknowledged.
References
Bailey, C. G., and Moore, D. B. (2000). “The structural behaviour of steel frames with composite floor slabs subject to fire. Part 2: Design.” Struct. Engineer Part A, 78(11), 28–33.
Bailey, C. G., and Toh, W. S. (2007). “Small-scale concrete slab tests at ambient and elevated temperatures.” Eng. Struct., 29(10), 2775–2791.
Cashell, K. A. (2009). “Failure assessment of floor slab systems under extreme loading conditions.” Ph.D. thesis, Imperial College London.
Cashell, K. A., Elghazouli, A. Y., and Izzuddin, B. A. (2010). “Experimental and analytical assessment of ductility in lightly reinforced concrete members.” Eng. Struct., 32(9), 2729–2743.
Cashell, K. A., Elghazouli, A. Y., and Izzuddin, B. A. (2011). “Failure assessment of lightly reinforced floor slabs. I: Experimental investigation.” J. Struct. Eng., 137(9), 977–988.
Clifton, G. C. (2006). “Design of composite steel floor systems for severe fires.” Report R4-131, New Zealand Heavy Engineering Research Association.
Elghazouli, A. Y., Cashell, K. A., and Izzuddin, B. A. (2009). “Experimental evaluation of the mechanical properties of steel reinforcement at elevated temperature.” Fire Saf. J., 44(6), 909–919.
Elghazouli, A. Y., and Izzuddin, B. A. (2001). “Analytical assessment of the structural performance of composite floors subject to compartment fires.” Fire Saf. J., 36, 769–793.
Elghazouli, A. Y., and Izzuddin, B. A. (2004). “Realistic modelling of composite and reinforced concrete floor slabs under extreme loading. II: Verification and application.” J. Struct. Eng., 130(12), 1985–1996.
European Committee for Standardization (CEN). (2004). “Design of concrete structures: Part 1.2: General rules—Structural fire design.” EN 1992 Eurocode 2, Brussels, Belgium.
Foster, S. J., Burgess, I. W., and Plank, R. (2004). “High-temperature experiments on model-scale concrete slabs at high displacements.” 3rd Int. Workshop for Structures in Fire, Ottawa, Canada.
International Organization for Standardization. (1999). “Fire resistance tests—Elements of building construction.” ISO 834, Geneva.
Izzuddin, B. A. (1991). “Nonlinear dynamic analysis of framed structures.” Ph.D. thesis, Imperial College, Univ. of London.
Izzuddin, B. A., and Elghazouli, A. Y. (2004). “Failure of lightly reinforced concrete members under fire. I: Analytical modelling.” J. Struct. Eng., 130(1), 3–17.
Izzuddin, B. A., and Moore, D. B. (2002). “Lessons from a full-scale fire test.” Proc. ICE Struct. Build., 152(4), 319–329.
Izzuddin, B. A., Tao, X. Y., and Elghazouli, A. Y. (2004). “Realistic modelling of composite and reinforced concrete floor slabs under extreme loading. I: Analytical method.” J. Struct. Eng., 130(12), 1972–1984.
Lim, L., Buchanan, A., and Moss, P. (2002). “Experimental testing and numerical modelling of two-way concrete slabs under fire conditions.” Struct. Eng. Soc. New Zealand J. 15(2), 12–26.
Morley, P. D., and Royles, R. (1983). “Response of the bond in reinforced concrete to high temperatures.” Magazine of Concrete Research, 35(123), 67–74.
Omer, E., Izzuddin, B. A., and Elghazouli, A. Y. (2006). “Failure assessment of simply supported floor slabs under elevated temperature.” Struct. Eng. Int., 16, 148–155.
Omer, E., Izzuddin, B. A., and Elghazouli, A. Y. (2010). “Failure of unrestrained lightly reinforced concrete slabs under fire, Part I: Analytical models.” Eng. Struct., 32(9), 2631–2646.
Sager, H., and Rostasy, F. S. (1982). “The effect of elevated temperature on the bond behavior of embedded reinforcing bars.” Bond in concrete, P. Bartos, ed., Applied Science, London, 206–216.
Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 137 • Issue 9 • September 2011
Pages: 989 - 1001
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Oct 18, 2010
Accepted: May 20, 2011
Published online: May 25, 2011
Published in print: Sep 1, 2011
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.