Arabian Journal for Science and Engineering

, Volume 37, Issue 2, pp 489–504 | Cite as

Numerical Analysis of Thermal Behavior of Concrete Cover Around FRP-Bars in Cold Region

  • Ali ZaidiEmail author
  • Radhouane Masmoudi
Research Article - Civil Engineering


The coefficient of thermal expansion of fiber reinforced polymer (FRP) in transverse direction is 3–8 times greater than that of hardened concrete. This thermal incompatibility between FRP bar and concrete in transverse direction may cause circumferential cracks within concrete at FRP bar/concrete interface under low temperatures and eventually the debonding of FRP bar from concrete. This paper presents numerical analysis using ADINA finite element software to investigate the thermal behavior of concrete cylinders reinforced with glass FRP bar (GFRP) in cold regions. The non-linear numerical results show that the first circumferential cracks occur within concrete at FRP bar/concrete interface at thermal loads ΔT cr varied between −35 and −25°C for GFRP bar-reinforced concrete cylinders having a ratio of concrete cover thickness to FRP bar diameter (c/d b) varied from 0.8 to 3.6 and a concrete tensile strength of 4.1 MPa. The numerical radial tensile stresses in concrete at the interface compared with those predicted from the analytical model are similar until the appearance of the circumferential cracks in concrete whose analytical results are greater. The ratio c/d b has no significant effect on the transverse thermal strains at FRP bar/concrete interface and also at external surface of concrete cover for a ratio of c/d b ≥ 1.5. Also, the transverse thermal strains, at external surface of concrete cover, predicted from non-linear numerical model are in good agreement with those obtained from the linear analytical model and experimental tests.


Bars Concrete cover Fiber reinforced polymers Low temperatures Thermal stresses Thermal strains 

List of Symbols


Radius of FRP bar


Radius of concrete cylinder


Concrete cover thickness


Bar diameter


Coefficient of thermal expansion


Modulus of elasticity of concrete


Longitudinal modulus of elasticity of FRP bar


Transverse modulus of elasticity of FRP bar

\({f^{\prime}_{{\rm c}28}}\)

Compressive strength of concrete


Tensile strength of concrete


Ultimate tensile strength of FRP bar


Radial pressure exerted by surrounding concrete on FRP bar


Ratio of radius of cylinder to that of FRP bar rb/a


Coefficient of thermal expansion of concrete


Longitudinal coefficient of thermal expansion of FRP bar


Transverse coefficient of thermal expansion of FRP bar


Temperature variation (thermal load)


Thermal load producing the first circumferential cracks in concrete at FRP bar/concrete interface

\({\varepsilon_{{\rm ct}}}\)

Circumferential strains in concrete

\({\varepsilon_{{\rm ft}}}\)

Circumferential strains in FRP bar


Poisson’s ratio of concrete


Transverse Poisson’s ratio of FRP bar


Longitudinal Poisson’s ratio of FRP bar


Radial tensile stress


Circumferential compressive stress


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  1. 1.
    Erki M.A., Rizkalla S.H.: FRP Reinforcement for Concrete Structures. Concret. Int. Design Constr 15, 48–53 (1993)Google Scholar
  2. 2.
    Nanni A.: Fiber-Reinforced-Plastic (FRP) Reinforcement for Concrete Structures: Properties and Applications, Developments in Civil Engineering, vol. 42. Elsevier Science Publishers, Amsterdam (1993)Google Scholar
  3. 3.
    Benmokrane, B.; El-Salakawy, E.: Proceedings of third International Conference on Durability and Field Applications of Fibre Reinforced Polymer (FRP) Composites for Construction, CDCC-07, Quebec City, Quebec, Canada (2007)Google Scholar
  4. 4.
    Zaidi A., Masmoudi R.: Thermal effect on Fiber reinforced polymer reinforced concrete slabs. Can. J. Civil Eng. NRC Canada 35, 312–320 (2008)CrossRefGoogle Scholar
  5. 5.
    Masmoudi R., Zaidi A., Gérard P.: Transverse Thermal Expansion of FRP bars Embedded in Concrete. J. Compos. Constr. ASCE 9, 377–387 (2005)CrossRefGoogle Scholar
  6. 6.
    Gentry T.R., Husain M.: Thermal compatibility of concrete and composite reinforcements. J. Compos. Constr. 3, 82–86 (1999)CrossRefGoogle Scholar
  7. 7.
    Chaallal O., Benmokrane B.: Physical and mechanical performance of innovative glass fiber reinforced plastic rod for concrete and grouted anchorages. Can. J. Civil Eng 20, 254–268 (1993)CrossRefGoogle Scholar
  8. 8.
    American Society for Testing and Materials. Standard test method for splitting Tensile strength of cylindrical concrete specimens. Annual Book Of Astm Standards ASTM C, 496-96, USA, vol. 04.2, pp. 281–284 (2002)Google Scholar
  9. 9.
    American Society for Testing and Materials. Standard test method for compressive strength of cylindrical concrete specimens. Annual Book Of Astm Standards ASTM C 39/C 39 M–01, USA, vol. 4.2, pp. 21–25 (2002)Google Scholar
  10. 10.
    Canadian Standards Association. Design and construction of building components with fiber-reinforced polymers. CAN/CSA–S806–02, Toronto, Ontario, Canada (2002)Google Scholar
  11. 11.
    Gay D.: Matériaux composites 4e édition. Hermès, Paris, France (1997)Google Scholar
  12. 12.
    Aiello M.A., Focacci F., Nanni A.: Effects of thermal loads on concrete cover of fiber reinforced polymer reinforced elements: theoretical and experimental analysis. ACI Mater. J. 98, 332–339 (2001)Google Scholar
  13. 13.
    Rahman, H.A.; Kingsley, C.Y.; Taylor, D.A.: Thermal stress in FRP reinforced concrete. In: Proceedings of the Annual Conference of the Canadian Society for Civil Engineering, CSCE, Ottawa, pp. 605–614 (1995)Google Scholar

Copyright information

© King Fahd University of Petroleum and Minerals 2012

Authors and Affiliations

  1. 1.Laboratory of Civil EngineeringUniversity of LaghouatLaghouatAlgeria
  2. 2.Department of Civil EngineeringUniversity of SherbrookeSherbrookeCanada

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