An Experimental study on the behavior of circular RCC enclosed GRP casing and FRP wrapping

Document Type : Research Article


1 Ph.D. student, Department of Civil Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran

2 Associate professor, Department of Civil Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran

3 Invited Assistant Professor, Department of Civil Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran and Assistant Professor, Department of Civil Engineering, Jundi Shapur University of Technology, Dezful, Iran


Nowadays, strengthening of the column using fiber-reinforced polymer (FRP) composites is considered as the strengthening technics of these loading elements in a structure. In this technique, increasing the surrounding pressure on radial levels of the concrete column increases the compressive and tensile strengths of the concrete element, reduces slenderness, and increases the buckling load and ductility of this element. Moreover, using glass-fiber reinforced plastic pipes (GRP) as the concrete column casing in addition to the independence of the need for framing leads to confinement effect on the concrete, high ductility and energy absorption, reduction in shrinkage and creep of concrete, lack of contact of the concrete with the corrosive factors, high construction speed, and proper loading capacity. In this research, a compressive capacity test was conducted on 6 cylinders reinforced concrete columns (RCC) of 150 mm and diameter 600 mm height, with and without GRP casing, and the effect of FRP wrapping was studied on them as the confining factor. The research results showed that using FRP wrapping and GRP casing improved the compressive capacity and ductility of the RCC. Adding one or two FRP wrapping layers increased the compressive capacity by 18.5% and 26.5% on the average, while using GRP casing increased the compressive capacity up to 4 times on the average and this shows that although FRP wrapping and GRP casing are both confined, GRP casing is more effective in increasing the compressive capacity due to its higher confinement with RCC.


Main Subjects

[1]  A. Mirmiran, M. Shahawy, Behavior of concrete columns confined by fiber composites, Journal of structural engineering, 123(5) (1997) 583-590.
[2]  M. Shahawy, A. Mirmiran, T. Beitelman, Tests and modeling of carbon-wrapped concrete columns, Composites Part B: Engineering, 31(6-7) (2000) 471480.
[3]  G. Wu, Z. Lü, Z. Wu, Strength and ductility of concrete cylinders confined with FRP composites, Construction and building materials, 20(3) (2006) 134-148.
[4]  S.A. Sheikh, Performance of concrete structures retrofitted with fibre reinforced polymers, Engineering structures, 24(7) (2002) 869-879.
[5]  Y. Wong, T. Yu, J. Teng, S. Dong, Behavior of FRPconfined concrete in annular section columns, Composites Part B: Engineering, 39(3) (2008) 451466.
[6]  A. Mirmiran, M. Shahawy, M. Samaan, H.E. Echary, J.C. Mastrapa, O. Pico, Effect of column parameters on FRP-confined concrete, Journal of Composites for construction, 2(4) (1998) 175-185.
[7]  T. El Maaddawy, M. El Sayed, B. Abdel-Magid, The effects of cross-sectional shape and loading condition on performance of reinforced concrete members confined with carbon fiber-reinforced polymers, Materials & Design (1980-2015), 31(5) (2010) 23302341.
[8]  T. Ozbakkaloglu, T. Xie, Geopolymer concrete-filled FRP tubes: Behavior of circular and square columns under axial compression, Composites Part B: Engineering, 96 (2016) 215-230.
[9]  A. Rahai, P. Sadeghian, M.R. Ehsani, Experimental behavior of concrete cylinders confined with CFRP composites, in:  Proceedings of the 14th World Conference on Earthquake Engineering, 2008.
[10]      R. Kumutha, R. Vaidyanathan, M. Palanichamy, Behaviour of reinforced concrete rectangular columns strengthened using GFRP, Cement and concrete composites, 29(8) (2007) 609-615.
[11]      A. Parvin, A.S. Jamwal, Effects of wrap thickness and ply configuration on composite-confined concrete cylinders, Composite structures, 67(4) (2005) 437-442. [12] T.H. Almusallam, Behavior of normal and highstrength concrete cylinders confined with E-glass/ epoxy composite laminates, Composites Part B: Engineering, 38(5-6) (2007) 629-639.
[13]  T. Vincent, T. Ozbakkaloglu, Influence of concrete strength and confinement method on axial compressive behavior of FRP confined high-and ultra high-strength concrete, Composites Part B: Engineering, 50 (2013) 413-428.
[14]  M. Samaan, A. Mirmiran, M. Shahawy, Model of concrete confined by fiber composites, Journal of structural engineering, 124(9) (1998) 1025-1031.
[15]  V.M. Karbhari, Y. Gao, Composite jacketed concrete under uniaxial compression—Verification of simple design equations, Journal of materials in civil engineering, 9(4) (1997) 185-193.
[16]  T. Ozbakkaloglu, J.C. Lim, T. Vincent, FRP-confined concrete in circular sections: Review and assessment of stress–strain models, Engineering Structures, 49 (2013) 1068-1088.
[17]  M.N. Youssef, M.Q. Feng, A.S. Mosallam, Stress–strain model for concrete confined by FRP composites, Composites Part B: Engineering, 38(5-6) (2007) 614628.
[18]  M.N. Hadi, Comparative study of eccentrically loaded FRP wrapped columns, Composite structures, 74(2) (2006) 127-135.
[19]  M.N. Hadi, Behaviour of FRP strengthened concrete columns under eccentric compression loading, Composite Structures, 77(1) (2007) 92-96.
[20]  M.N. Hadi, The behaviour of FRP wrapped HSC columns under different eccentric loads, Composite Structures, 78(4) (2007) 560-566.
[21]  T. Ozbakkaloglu, Axial compressive behavior of square and rectangular high-strength concrete-filled FRP tubes, Journal of Composites for Construction, .161-151 )3102( )1(71
[22]  A.R. Malik, S.J. Foster, Carbon Fiber-Reinforced Polymer Confined Reactive Powder Concrete Columns--Experimental Investigation, ACI Structural Journal, 107(3) (2010).
[23]  J. Xiao, J. Tresserras, V.W. Tam, GFRP-tube confined RAC under axial and eccentric loading with and without expansive agent, Construction and Building Materials, 73 (2014) 575-585.
[24]  A.Q.L. Al-Baali, Behaviour of fibre-reinforced polymer (FRP) tube reinforced concrete (FTRC) specimens under different loading conditions,  (2016).
[25]  M.N. Hadi, W. Wang, M.N. Sheikh, Axial compressive behaviour of GFRP tube reinforced concrete columns, Construction and Building Materials, 81 (2015) 198207.
[26]  W. Wang, M.N. Sheikh, M.N. Hadi, D. Gao, G. Chen, Behaviour of concrete-encased concrete-filled FRP tube (CCFT) columns under axial compression, Engineering Structures, 147 (2017) 256-268.
[27]  Y.F. Yang, L.H. Han, X. Wu, Concrete shrinkage and creep in recycled aggregate concrete-filled steel tubes, Advances in Structural Engineering, 11(4) (2008) 383396.
[28]  L.H. Ichinose, E. Watanabe, H. Nakai, An experimental study on creep of concrete filled steel pipes, Journal of Constructional Steel Research, 57(4) (2001) 453-466.
[29]  K. Shrestha, B.-c. Chen, Y.-f. Chen, State of the art of creep of concrete filled steel tubular arches, KSCE Journal of Civil Engineering, 15(1) (2011) 145-151.
[30]  D. Astm, Standard test method for determining tensile properties of fibre reinforced polymer matrix composites used for strengthening of civil structures, in, ASTM West Conshohocken, PA, 2010.
[31]  B. ASTM, D2996-Standard Specification for Filament-Wound" Fiberglass, Glass-Fiber-Reinforced Thermosetting-Resin) Pipe,  (2001).
[32]  A. International, Standard test method for tensile properties of plastics, ASTM International, 2014.
[33]  A. Standard, Standard practice for selecting proportions for normal, heavyweight, and mass concrete, ACI Manual of Concrete Practice,  (1996) .83-1
[34]  A.I.C.C.o. Concrete, C. Aggregates, Standard test method for compressive strength of cylindrical concrete specimens, ASTM International, 2014.
[35]  D.M.N. ISIS Canada, Canadian Network of Centers of Excellence on Intelligent Sensing for Innovative Structures, in, ISIS Canada Corporation Winnipeg (Spring), 2001.