Experimental and Numerical Study of FRP Encased Composite Concrete Columns

Document Type : Original Article


1 PhD student, AmirKabir University of Technology, Tehran, Iran

2 Associate professor, Amirkabir University of Technology, Tehran, Iran


A new type of composite column is presented and assessed through experimental testing and numerical modeling. The objective of this research is to investigate design options for a composite column without the use of ferrous materials. This is to avoid the current problem of deterioration of concrete due to expansion of rusting reinforcement members. Such a target can be achieved by replacing the steel reinforcement of concrete columns with pultruded I-shape glass FRP structural sections. The composite column utilizes a glass FRP tube that surrounds a pultruded I-section glass FRP, which is subsequently filled with concrete. The GFRP tube acts as a stay-in-place form in addition to providing confinement to the concrete. A total of four composite columns were tested under monotonic axial loading. The experimental ultimate capacity of each of the tested composite column was compared to the predicted numerical capacity using ANSYS program. The comparison showed that the predicted numerical values were in good agreement with the experimental ones.


Main Subjects

[1] Teng JG, Yu T, Wong YL, Dong SL. Hybrid FRP-concrete-steel tubular columns: concept and behaviour. Journal of Constructional Build Material 2007; 21:846-854.
[2] Wu HL, Wang YF, Yu L, Li XR. Experimental and computational studies on high strength concrete circular columns confined by aramid fiber-reinforced polymer sheets. Journal of Composite Construction 2009;13(2):125–34.
[3] Phama TM, Youssed J. Effect of Different FRP Wrapping Arrangements on the Confinement Mechanism. Procedia Engineering 2016; 142: 307 – 313.
[4] Hadi M, Khan QS, Sheikh MN. Axial and flexural behavior of unreinforced and FRP bar reinforced circular concrete filled FRP tube columns. Journal of Construction Build Material 2016; 122: 43–53.
[5] ElGawady MA, Booker AJ, H.M. Dawood HM. Seismic behavior of post tensioned concrete-filled fiber tubes. J Composite Construction ASCE 2010; 14 (5): 616–628.
[6] Huang L, Sun X, Yan L, Zhu D. Compressive behavior of concrete confined with GFRP tubes and steel spirals. Polymers 2015; 7 (5): 851–875.
[7] Ozbakkaloglu T. A novel FRP-dual-grade concrete-steel composite column system. Thin-Walled Structures 2015; 96: 295–306.
[8] Ozbakkaloglu T. Behavior of square and rectangular ultrahigh-strength concrete-filled FRP tubes under axial compression. Compos B Engineering 2013; 54: 97–111.
[9] Dundar C, Erturkmen D, Tokgoz S. Studies on carbon fiber polymer confined slender plain and steel fiber reinforced concrete columns. Engineering Structures 2015; 102: 31–39.
[10] Ozbakkaloglu T, Oehlers DJ. Manufacture and testing of a novel FRP tube confinement system”, Engineering Structures 2008; 30(9): 2448-59.
[11] Kian Karimi K, Tait MJ, El-Dakhakhni WW. Testing and modeling of a novel FRP-encased steel–concrete composite column. Journal of composite structures 2011; 93(5): 1463-73.
[12] Yu T, Lin G, Zhang SS. Compressive behavior of FRP-confined concrete-encased steel columns. Composite Structure 2016; 154: 493–506.
[13] Ashraf Biddah. Structural reinforcement of bridge decks using pultruded GFRP grating. Journal of Composite Structures 2008;74: 80-88.
[14] ANSYS User manual 12.0. Release 12.0, ANSYS, Inc; 2014.
[15] Willam KJ, Warnke ED. Constitutive model for the triaxial behavior of concrete. Proceedings of the international association for bridge and structural engineering 1975; 19: 1-30.
[16] Tsai SW, Wu EMA. General theory of anisotropic materials. Journal of Composite Materials 1971; 5: 58-80.
Volume 3, Issue 4 - Serial Number 9
March 2017
Pages 139-147
  • Receive Date: 22 August 2016
  • Revise Date: 27 October 2016
  • Accept Date: 26 December 2016
  • First Publish Date: 19 February 2017