CFRP-Strengthened HSS Columns Subject to Eccentric Loading
Publication: Journal of Composites for Construction
Volume 22, Issue 4
Abstract
Carbon fiber–reinforced polymer (CFRP) laminates are widely used in strengthening reinforced concrete slabs, beams, and columns. However, the application of this advanced composite material to strengthen steel structures is still evolving, and more research is needed to facilitate deployment. This paper presents the results of an experimental program aimed at investigating the behavior of steel columns subject to eccentric loading and strengthened using bonded high-modulus CFRP laminates. Thirty hollow steel section (HSS) column specimens () were eccentrically loaded to failure using load eccentricity values of 25, 50, and 100 mm. The efficiency of bonding the CFRP laminates to the HSS column in enhancing the column’s capacity was evaluated for different column slenderness ratios () ranging between 68 and 131. Depending on the slenderness ratio and the load eccentricity, it was found that the increase in axial load capacity of the CFRP-strengthened columns ranged between 40 and 107%, and the increase in the ultimate moment ranged between 34 and 135%; the maximum increase in a column’s capacity corresponded to the medium column slenderness ratio. Two successive failure modes for the strengthened HSS columns were encountered: CFRP laminates debonding and flexural buckling of the column. Flexural buckling was the dominant mode of failure for all the unstrengthened columns (control specimens). On the other hand, debonding of CFRP laminates was observed either before or after flexural buckling for the strengthened columns depending on the load eccentricity value and the slenderness ratio.
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Acknowledgments
In-kind support was received from S&P Clever Reinforcement Co. (Austria) in the form of providing the CFRP laminates used in the experimental work. The authors are very grateful for this support.
References
AISC (American Institute of Steel Construction). 2010. Specification for structural steel buildings. ANSI/AISC 360-10. Chicago, IL: AISC.
Alam, M. I., S. Fawzia, and X. Zhao. 2016. “Numerical investigation of CFRP strengthened full scale CFST columns subjected to vehicular impact.” Eng. Struct. 126 (Nov): 292–310. https://doi.org/10.1016/j.engstruct.2016.07.058.
Attiah, W., A. A. Shaat, and E. Y. Sayed-Ahmed. 2017. “Numerical investigation into the behaviour of HSS beam-columns strengthened using CFRP plates.” In Proc., 16th Int. Symp. on Tubular Structures, 487–493. Boca Raton, FL: CRC Press.
Bambach, M., H. Jama, and M. Elchalakani. 2009. “Axial capacity and design of thin-walled steel SHS strengthened with CFRP.” Thin-Walled Struct. 47 (10): 1112–1121. https://doi.org/10.1016/j.tws.2008.10.006.
BSI (British Standards Institution). 2005. Eurocode 3: Design of steel structures. London, UK: BSI.
Gao, X., T. Balendra, and C. Koh. 2013. “Buckling strength of slender circular tubular steel braces strengthened by CFRP.” Eng. Struct. 46 (Jan): 547–556. https://doi.org/10.1016/j.engstruct.2012.08.010.
Ghumatkar, A. K., S. A. Budhe, R. A. Sekhar, M. D. Banea, and S. D. Barros. 2016. “Influence of adherend surface roughness on the adhesive bond strength.” Lat. Am. J. Solids Struct. 13 (13): 2356–2370. https://doi.org/10.1590/1679-78253066.
Haedir, J., and X. L. Zhao. 2011. “Design of short CFRP-reinforced steel tubular columns.” J. Constr. Steel Res. 67 (3): 497–509.
Harries, K. A., A. J. Peck, and E. J. Abraham. 2009. “Enhancing stability of structural steel sections using FRP.” Thin-Walled Struct. 47 (10): 1092–1101. https://doi.org/10.1016/j.tws.2008.10.007.
Movaghati, S., and A. Rahai. 2012. “Eccentric compression loading test on steel HSS columns externally strengthened with CFRP composite materials.” In Proc., 6th Int. Conf. on FRP Composite in Civil Engineering (CICE2012). Kingston, ON, Canada: International Institute for FRP in Construction.
Ragheb, W. F. 2015. “Elastic local buckling of steel i-sections strengthened with bonded FRP strips.” J. Constr. Steel Res. 107 (Apr): 81–93.
Sayed-Ahmed, E. Y. 2004. “Strengthening of thin-walled steel i-section beams using CFRP strips.” In Proc., 4th Int. Conf. on Advanced Composite Materials in Bridges and Structures (ACMBS IV). Calgary, AB, Canada: University of Calgary and ISIS Canada Network of Centres of Excellence.
Sayed-Ahmed, E. Y. 2006. “Numerical investigation into strengthening steel I-section beams using CFRP strips.” In Proc., Structures Congress, 1–8. Reston, VA: ASCE.
Shaat, A. 2007. “Structural behaviour of steel columns and steel-concrete composite girders retrofitted using CFRP.” Ph.D. thesis, Dept. of Civil Engineering, Queen’s Univ.
Shaat, A., and A. Fam. 2006. “Axial loading tests on short and long hollow structural steel columns retrofitted using carbon fibre reinforced polymers.” Can. J. Civ. Eng. 33 (4): 458–470. https://doi.org/10.1139/l05-042.
Shaat, A., and A. Fam. 2007. “Finite element analysis of slender HSS columns strengthened with high modulus composites.” Steel Compos. Struct. 7 (1): 19–34.
Shaat, A., and A. Fam. 2009. “Slender steel columns strengthened using high-modulus CFRP plates for buckling control.” J. Compos. Constr. 13 (1): 2–12. https://doi.org/10.1061/(ASCE)1090-0268(2009)13:1(2).
Standard Australia. 1998. Steel structures. AS 4100-1998. Sydney, Australia: Standard Australia.
Sundarraja, M. C., and G. Prabhu. 2013. “Flexural behaviour of CFST members strengthened using CFRP composites.” Steel Compos. Struct. 15 (6): 623–643. https://doi.org/10.12989/scs.2013.15.6.623.
Teng, J. G., and Y. M. Hu. 2007. “Behaviour of FRP-jacketed circular steel tubes and cylindrical shells under axial compression.” Constr. Build. Mater. 21 (4): 827–883.
Wang, Z., Q. Yu, and Z. Tao. 2015. “Behaviour of CFRP externally-reinforced circular CFST members under combined tension and bending.” J. Constr. Steel Res. 106 (Mar): 122–137. https://doi.org/10.1016/j.jcsr.2014.12.007.
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Published In
Journal of Composites for Construction
Volume 22 • Issue 4 • August 2018
Copyright
©2018 American Society of Civil Engineers.
History
Received: Mar 28, 2017
Accepted: Mar 12, 2018
Published online: Jun 15, 2018
Published in print: Aug 1, 2018
Discussion open until: Nov 15, 2018
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