Abstract
This paper reports the results on an experimental investigation on the efficiency of confinement with carbon fiber reinforced polymer (CFRP) in retrofitting square reinforced concrete (RC) columns. The study was designed to evaluate the effect of the recently developed corner strip-batten (CSB) method on the seismic behavior of RC columns. In the CSB method, FRP battens are bonded, similar to flat coupons, at the sides of the section while each adheres on the CFRP corner strips at the two ends. For the purposes of this study, five large-scale RC columns were subjected to constant axial and cyclic lateral loads. The main parameter examined was the method employed for confining the columns. The RC columns were investigated in terms of their failure mode, hysteretic and envelope curve, enhanced lateral strength and ductility, equivalent damping ratio, stiffness degradation, and energy dissipation. The results indicated that RC columns retrofitted with CFRP composites exhibited a ductile behavior under cyclic lateral loading. Furthermore, seismic loading tests revealed that the transverse FRP sheets applied through recently developed CSB technique at the potential plastic hinge areas led to considerable enhancements in lateral strength, energy dissipation, and ductility. This is evidenced by enhancements of 51.6%, 30.3%, 27.2% and 24.6%, respectively, in the ductility, equivalent viscous damping ratio, energy dissipation, and lateral strength of columns retrofitted via the CSB technique, relative to the control column.
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References
Wu G, Lu ZT, Wu ZS (2006) Strength and ductility of concrete cylinders confined with FRP composites. Constr Build Mater 20(3):134–148
Lam L, Teng JG (2003) Design-oriented stress-strain model for FRP-confined concrete. Constr Build Mater 17(6–7):471–489
Wu YF, Liu T, Oehlers DJ (2006) Fundamental principles that govern retrofitting of reinforced concrete columns by steel and FRP jacketing. Adv Struct Eng 9(4):507–533
Saljoughian A, Mostofinejad D (2015) Axial-flexural interaction in square RC columns confined by intermittent CFRP wraps. Compos Part B Eng 89:85–95
Barros JAO, Ferreira DRSM (2008) Assessing the efficiency of CFRP discrete confinement systems for concrete cylinders. J Compos Constr 12(2):134–148
Chaallal O, Hassan M, Shahawy M (2003) Confinement model for axially loaded short rectangular columns strengthened with fiber-reinforced polymer wrapping. ACI Struct J 100(2):215–221
Au C, Buyukozturk O (2005) Effect of fiber orientation and ply mix on fiber reinforced polymer-confined concrete. J Compos Constr 9(5):397–407
Bisby L, Ranger M (2010) Axial-flexural interaction in circular FRP-confined reinforced concrete columns. Constr Build Mater 24:1672–1681
El-Maaddawy T, El-Sayed M, Abdel-Magid B (2010) The effects of cross-sectional shape and loading condition on performance of reinforced concrete members confined with carbon fiber-reinforced polymers. Mater Des 31:2330–2341
Quiertant M, Clement JL (2011) Behavior of RC columns strengthened with different CFRP systems under eccentric loading. Constr Build Mater 25:452–460
Nistico N, Monti G (2013) RC square sections confined by FRP: analytical prediction of peak strength. Compos Part B Eng 45:127–137
Marques PF, Chastre C (2012) Performance analysis of load-strain models for circular columns confined with FRP composites. Compos Struct 94:3115–3131
Lignola GP, Nardone F, Prota A, Manfredi G (2012) Analytical model for the effective strain in FRP-wrapped circular RC columns. Compos Part B Eng 43:3208–3218
Wang ZY, Wang DY, Smith ST, Lu DG (2012) Experimental testing and analytical modeling of CFRP-confined large circular RC columns subjected to cyclic axial compression. Eng Struct 40:64–74
Li P, Wu YF (2016) Stress-strain behavior of actively and passively confined concrete under cyclic axial load. Compos Struct 149:369–384
Yu T, Zhang B, Teng JG (2015) Unified cyclic stress-strain model for normal and high strength concrete confined with FRP. Eng Struct 102:189–201
Wang D, Wang Z, Smith ST, Yu T (2017) Seismic performance of CFRP-confined circular high-strength concrete columns with high axial compression ratio. Constr Build Mater 134:91–103
Kim J, Kwon M, Jung W, Limkatanyu S (2013) Seismic performance of RC columns reinforced by GFRP composite sheets with clip connectors. Constr Build Mater 43:563–574
Rodrigues H, Arede A, Furtado A, Rocha P (2015) Seismic behavior of strengthened RC columns under biaxial loading: an experimental characterization. Constr Build Mater 95:393–405
Memon MS, Sheikh SA (2005) Seismic resistance of square concrete columns retrofitted with glass fiber-reinforced polymer. ACI Struct J 102(5):774–783
Ghosh KK, Sheikh SA (2007) Seismic upgrade with carbon fiber-reinforced polymer of columns containing lap-spliced reinforcing bars. ACI Struct J 104(2):227–236
Harries KA, Ricles JR, Pessiki S, Sause R (2006) Seismic retrofit of lap splices in nonductile square columns using carbon fiber-reinforced jackets. ACI Struct J 103(6):874–884
Sause R, Harries KA, Walkup SL, Pessiki S, Ricles JM (2004) Flexural behavior of concrete columns retrofitted with carbon fiber-reinforced polymer jackets. ACI Struct J 101(5):708–716
Bousias SN, Fardis MN, Biskinis D (2005) Retrofit of RC columns with deficient lap spliced. In: Proceedings of fib symposium, Budapest, Hungary
Bournas DA, Lontou PV, Papanicolaou CG, Triantafillou TC (2007) Textile-reinforced mortar versus fiber-reinforced polymer confinement in reinforced concrete columns. ACI Struct J 104(6):740–748
Mirmiran A, Shahawy M, Samaan M, El-Echary H, Mastrapa JC, Pico O (1998) Effect of column parameters on FRP-confined concrete. J Compos Constr 2(4):175–185
Mostofinejad D, Ilia E, Mortazavi N (2018) Fiber-reinforced polymer efficiency in square RC columns with different corner radii. Proc Inst Civ Eng Struct Build 171(3):241–252
Wang LM, Wu YF (2008) Effect of corner radius on the performance of CFRP-confined square concrete columns: test. Eng Struct 30:493–505
Abbasnia R, Hosseinpour M, Rostamian M, Ziaadiny H (2012) Effect of corner radius on stress-strain behavior of FRP confined prisms under axial cyclic compression. Eng Struct 40:529–535
Mostofinejad D, Ilia E (2014) Confining of square RC columns with FRP sheets using corner strip-batten technique. Constr Build Mater 70:269–278
Campione G (2006) Influence of FRP wrapping techniques on the compressive behavior of concrete prisms. Cement Concr Compos 28:497–505
Saljoughian A, Mostofinejad D (2016) Corner strip-batten technique for FRP confinement of square RC columns under eccentric loading. J Compos Constr 20(3):04015077
Saljoughian A, Mostofinejad D (2017) Rectangular reinforced concrete columns strengthened with carbon fiber-reinforced polymer sheets using corner strip-batten method. ACI Struct J 114(3):659–671
ACI 318-14 (2014) Building code requirements for structural concrete and commentary. American Concrete Institute, Farmington Hills
Sika group (2006) Product data sheet. SikaWrap-300C, Woven carbon fiber fabric for structural strengthening
ACI 374.1-05 (2005) Acceptance criteria for moment frames based on structural testing and commentary. American Concrete Institute, Farmington Hills
Park R (1989) Evaluation of ductility of structures and structural assembles from laboratory testing. Bull N Z Soc Earth Eng 22(3):155–166
Paulay T, Priestley M (1992) Seismic design of reinforced concrete and masonry buildings. Wiley, New York
Priestley M, Park R (1987) Strength and ductility of concrete bridge columns under seismic loading. ACI Struct J 84(1):61–76
Hadi MNS (2009) Behavior of eccentric loading of FRP confined fiber steel reinforced concrete columns. Constr Build Mater 23:1102–1108
Mayes RL, Clough RW (1975) State the art in seismic shear strength of masonry: an evaluation and review. In: EERC report, Berkeley, California, USA
Cai ZK, Wang DY, Smith ST, Wang ZY (2016) Experimental investigation on the seismic performance of GFRP-wrapped thin-walled steel tube confined RC columns. Eng Struct 110:269–280
Priestley M, Seible F, Calvi GM (1996) Seismic design and retrofit of bridges. Wiley, New York
Acknowledgements
The authors would like to extend their gratitude to the staff of structural laboratory of Isfahan University of Technology (IUT) for their generous help, also to the managers of the Deesman Company, especially Eng. Aghayi for the invaluable support he lent us for constructing the experimental columns. The authors would also like to acknowledge Eng. Jamali from Pishro Sanat Co. for providing support on testing apparatus.
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Saljoughian, A., Mostofinejad, D. & Hosseini, S.M. CFRP confinement in retrofitted RC columns via CSB technique under reversed lateral cyclic loading. Mater Struct 52, 67 (2019). https://doi.org/10.1617/s11527-019-1373-6
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DOI: https://doi.org/10.1617/s11527-019-1373-6