Experimental and Numerical Study of Postfire Strengthening Methods for Fire-Damaged Two-Way Composite-Topped Precast Concrete Slabs
Publication: Journal of Composites for Construction
Volume 26, Issue 6
Abstract
The results of an experimental study of the flexural performance of full-scale, fire-damaged, two-way composite-topped precast concrete slabs with different postfire exposure-strengthening methods are presented. Four slabs were subjected to the standard ISO 834 fire conditions for varying exposure times (30, 60, 90 min and failure at 133 min). A fifth control slab was tested without having been exposed to fire conditions. Different strengthening methods, selected based upon the extent of fire damage, included externally bonded carbon fiber–reinforced polymer (CFRP) sheets, steel strips, and combining CFRP sheets and midspan I-beam support were demonstrated to restore fire-damaged slab load-bearing capacity, although postfire exposure stiffness was degraded in every case. Load-carrying capacity of the strengthened fire-damaged slabs was increased at least 23% over the capacity of the control specimen without strengthening. Finite-element modeling combining an initial thermal analysis followed by a mechanical analysis which accounted for temperature-degraded material properties was conducted to capture the mechanical behavior of the strengthened slabs after fire. The results were shown to correlate well with experimentally determined results, exhibiting conservative errors of less than 20%.
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Acknowledgments
This research was supported financially by the National Key R&D Program of China (No. 2016YFC0701306) and Shanghai Science and Technology Commission Standard Program (No. 17DZ2202600). The authors gratefully acknowledge the support.
References
ABAQUS. 2010. ABAQUS v6.10. User’s manual. Providence, RI: Dassault System Simulia Corp.
Bailey, C. G. 2004. “Membrane action of slab/beam composite floor systems in fire.” Eng. Struct. 26 (12): 1691–1703. https://doi.org/10.1016/j.engstruct.2004.06.006.
Bailey, C. G., and W. S. Toh. 2007. “Behaviour of concrete floor slabs at ambient and elevated temperatures.” Fire Saf. J. 42 (6–7): 425–436. https://doi.org/10.1016/j.firesaf.2006.11.009.
Bailey, C. G., D. S. White, and D. B. Moore. 2000. “The tensile membrane action of unrestrained composite slabs simulated under fire conditions.” Eng. Struct. 22 (12): 1583–1595. https://doi.org/10.1016/S0141-0296(99)00110-8.
BSI (British Standards Institution). 2002. Eurocode 1: Actions on structures. Part 1-2: General actions -actions on structures exposed to fire. BS EN 1992-1-1. London: BSI.
BSI (British Standards Institution). 2005. Eurocode 4: Design of composite steel and concrete structures. Part 1-2: General rules-structural fire design. BS EN 1994-1-2. London: BSI.
CSI (Chinese Standards Institution). 2009. Standard for test method of performance on building mortar. JG/T 70-2009. Beijing: China Architecture and Building Press.
CSI (Chinese Standards Institution). 2019. Standard for appraisal of engineering structures after fire. T/CECS 252-2019. Beijing: China Architecture and Building Press.
Dong, Y.-L., and Y.-Y. Fang. 2010. “Determination of tensile membrane effects by segment equilibrium.” Mag. Concr. Res. 62 (1): 17–23. https://doi.org/10.1680/macr.2008.62.1.17.
Ebead, U., and H. Marzouk. 2004. “Strengthening of two-way slabs using steel plates.” ACI Struct. J. 99 (1): 23–31.
Feng, P., L. Qiang, and L. Ye. 2017. “Discussion and definition on yield points of materials, members and structures.” [In Chinese.] Eng. Mech. 34 (3): 36–46.
GB (Guobiao Standards). 2002a. Metallic materials-tensile testing at ambient temperature. GB/T 228-2002. Beijing: China Standard Press.
GB (Guobiao Standards). 2002b. Standard for test methods of concrete physical and mechanical properties. GB/T 50081-2002. Beijing: China Architecture and Building Press.
GB (Guobiao Standards). 2008. Fire-resistance tests: Elements of building construction: Part 1: General requirements. GB/T 9978.1-2008. Beijing: China Standards Press.
GB (Guobiao Standards). 2011. Technical code for safety appraisal of engineering structural strengthening materials. GB 50728-2011. Beijing: China Architecture and Building Press.
GB (Guobiao Standards). 2012. Standard for test method of concrete structures. GB/T 50152-2012. Beijing: China Architecture and Building Press.
GB (Guobiao Standards). 2013. Code for design of strengthening concrete structure. GB 50367-2013. Beijing: China Architecture and Building Press.
GB (Guobiao Standards). 2015. Code for design of concrete structures (2015 edition). GB 50010-2010. Beijing: China Architecture and Building Press.
GB (Guobiao Standards). 2016. Technical code for precast concrete buildings. GB/T 51231-2016. Beijing: China Architecture and Building Press.
Gu, X., X. Jin, and Y. Zhou. 2016. Basic principles of concrete structures. Shanghai, China: Springer-Verlag Berlin Heidelberg and Tongji University Press.
Guo, Z., and X. Shi. 2003. Behaviour of reinforced concrete at elevated temperature and its calculation. Beijing: Tsinghua University Press.
ISO (International Organization for Standardization). 2014. Fire resistance tests – Elements of building construction - part 11: Specific requirements for the assessment of fire protection to structural steel elements. ISO 834-11. Geneva: ISO.
Kodur, V. K. R., and A. Agrawal. 2017. “Effect of temperature induced bond degradation on fire response of reinforced concrete beams.” Eng. Struct. 142: 98–109. https://doi.org/10.1016/j.engstruct.2017.03.022.
Lee, J., and G. L. Fenves. 1998. “Plastic-damage model for cyclic loading of concrete structures.” J. Eng. Mech. 124 (8): 892–900. https://doi.org/10.1061/(ASCE)0733-9399(1998)124:8(892).
Li, G.-Q., N. Zhang, and J. Jiang. 2017. “Experimental investigation on thermal and mechanical behaviour of composite floors exposed to standard fire.” Fire Saf. J. 89: 63–76. https://doi.org/10.1016/j.firesaf.2017.02.009.
Lie, T., and R. J. Irwin. 1995. “Fire resistance of rectangular steel columns filled with bar-reinforced concrete.” J. Struct. Eng. 121 (5): 797–805. https://doi.org/10.1061/(ASCE)0733-9445(1995)121:5(797).
Lim, L., A. Buchanan, P. Moss, and J. M. Franssen. 2004. “Numerical modeling of two-way reinforced concrete slabs in fire.” Eng. Struct. 26 (8): 1081–1091. https://doi.org/10.1016/j.engstruct.2004.03.009.
Lim, L., and C. Wade. 2002. Experimental fire tests of two-way concrete slabs. Christchurch, New Zealand: Univ. of Canterbury.
Lubliner, J., J. Oliver, S. Oller, and E. Oñate. 1989. “A plastic-damage model for concrete.” Int. J. Solids Struct. 25 (3): 299–326. https://doi.org/10.1016/0020-7683(89)90050-4.
Mosallam, A. S., and K. M. Mosalam. 2003. “Strengthening of two-way concrete slabs with FRP composite laminates.” Constr. Build. Mater. 17 (1): 43–54. https://doi.org/10.1016/S0950-0618(02)00092-2.
Newman, A. 2001. Structural renovation of buildings. New York: McGraw Hill.
Pessiki, S., K. A. Harries, J. Kestner, R. Sause, and J. M. Ricles. 2001. “Axial behavior of reinforced concrete columns confined with FRP jackets.” J. Compos. Constr. 5 (4): 237–245. https://doi.org/10.1061/(ASCE)1090-0268(2001)5:4(237).
Thanoon, W. A., M. S. Jaafar, R. A. Kadir, and J. Noorzaei. 2005. “Repair and structural performance of initially cracked reinforced concrete slabs.” Constr. Build. Mater. 19 (8): 595–603. https://doi.org/10.1016/j.conbuildmat.2005.01.011.
Wang, B., and Y. Dong. 2009. “Experimental research of four-edge simple support two-way reinforced concrete slab under fire.” [In Chinese.] J. Build. Struct. 30 (6): 23–33.
Wang, B., and Y. Dong. 2010. “Experimental study of two-way reinforced concrete slabs under fire.” [In Chinese.] China Civ. Eng. J. 43 (4): 53–62.
Wang, Y., Y. L. Dong, and G. C. Zhou. 2013. “Nonlinear numerical modeling of two-way reinforced concrete slabs subjected to fire.” Comput. Struct. 119: 23–36. https://doi.org/10.1016/j.compstruc.2012.12.029.
Wang, Y., G. Yuan, Z. Huang, J. Lyu, Q. Li, and B. Long. 2018. “Modeling of reinforced concrete slabs in fire.” Fire Saf. J. 100: 171–185. https://doi.org/10.1016/j.firesaf.2018.08.005.
Xu, Q., L. Chen, C. Han, and Y. Zhang. 2018. “Experimental research on flexural behavior of PC composite slabs with boundary constraints after fire.” [In Chinese.] China Civ. Eng. J. 51 (11): 95–103.
Xu, Q., L. Chen, X. Li, C. Han, Y. C. Wang, and Y. Zhang. 2020. “Comparative experimental study of fire resistance of two-way restrained and unrestrained precast concrete composite slabs.” Fire Saf. J. 118: 103225. https://doi.org/10.1016/j.firesaf.2020.103225.
Zhang, J., Z. Lv, J. Teng, and Y. Huang. 2001a. “Study on the behavior and strength of the RC two-way slabs bonded with CFRP or steel strips.” [In Chinese.] J. Build. Struct. 22 (4): 42–48.
Zhang, J. W., J. G. Teng, Y. L. Wong, and Z. T. Lu. 2001b. “Behavior of two-way RC slabs externally bonded with steel plate.” J. Struct. Eng. 127 (4): 390–397. https://doi.org/10.1061/(ASCE)0733-9445(2001)127:4(390).
Zhu, J., B. Cao, and Q. Xu. 2019. “Experimental research on fire-damaged precast concrete composite slabs strengthened with CFRP sheets.” [In Chinese.] Constr. Technol. 48 (15): 1–5.
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© 2022 American Society of Civil Engineers.
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Received: Jan 17, 2022
Accepted: Jun 5, 2022
Published online: Aug 24, 2022
Published in print: Dec 1, 2022
Discussion open until: Jan 24, 2023
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