Statistical analysis and theoretical predictions of the tensile-strength retention of glass fiber-reinforced polymer bars based on resin type

Abstract

This paper presents experimental investigation, statistical analysis, and theoretical predictions of tensile-strength retention of glass fiber-reinforced polymer bars, made with vinyl-ester, polyester, or epoxy resins. The durability of glass fiber-reinforced polymer bars was evaluated as a function of time of immersion in alkaline solution. The aging of the three glass fiber-reinforced polymer bar types consisted of immersion glass fiber-reinforced polymer bar samples in an alkaline solution (up to 5000 h) at different elevated exposure temperatures. Subsequently, the physical and tensile properties of the unconditioned bars were compared with that of the conditioned bars to assess the durability performance of the glass fiber-reinforced polymer bars. Microstructure of all of the glass fiber-reinforced polymer bar types was investigated with scanning electron microscopy, energy dispersive spectroscopy, and Fourier transform infrared spectroscopy for both the conditioned and unconditioned cases, to qualitatively explain the experimental results and to assess changes and/or degradation in the glass fiber-reinforced polymer bars. In addition, the long-term performance of glass fiber-reinforced polymer bars was assessed considering the effect of service years, environmental humidity, and seasonal temperature fluctuations. The test results showed that the tensile strength of the glass fiber-reinforced polymer bars was affected by increased immersion time at higher temperatures and the reduction in tensile strength was statistically significantly dependent on the type of resin system. The prediction approach of the glass fiber-reinforced polymer bars based on the environmental reduction factor (C_E) after 200 years indicated that the C_E values for vinyl-ester, epoxy, and polyester glass fiber-reinforced polymer bars can be conservatively recommended to 0.81, 0.75, and 0.71, respectively, for a moisture-saturated environment (relative humidity = 100%) and at 30℃. The polyester glass fiber-reinforced polymer bars experienced greater debonding at the fiber–resin interface than the vinyl-ester and epoxy glass fiber-reinforced polymer bars.

Keywords

Glass fiber-reinforced polymer bars alkaline tensile strength durability resin service life

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References

American Concrete Institute (ACI). Guide for the design and construction of structural concrete reinforced with FRP bars. ACI 440.1R-15, Farmington Hills, MI, 2015.

Wang

Zhao

et al.

Interlaminar shear behavior of basalt FRP and hybrid FRP laminates. J Compos Mater 2016; 50: 1073–1084.

Won

Park

. Effect of environmental exposure on the mechanical and bonding properties of hybrid FRP reinforcing bars for concrete structures. J Compos Mater 2006; 40: 1063–1076.

Shen

Ojha

Shi

et al.

Bond stress–slip relationship between basalt fiber-reinforced polymer bars and concrete using a pull-out test. J Reinf Plast Compos 2016; 35: 747–763.

Benmokrane

Wang

Ton-That

et al.

Durability of GFRP reinforcing bars in concrete. J Compos Constr 2002; 6: 143–155.

Kocaoz

Samaranayake

Nanni

. Tensile characterization of glass FRP bars. Compos Eng 2005; 36: 127–134.

Benmokrane B, Ali AH and Mohamed HM. Durability performance and service life of CFCC tendons exposed to elevated temperature and alkaline environment. J Compos Constr 2016; 20(1): 1–13.

Davalos

Chen

Ray

. Long-term durability prediction models for GFRP bars in concrete environment. J Compos Mater 2012; 46: 1899–1914.

Portnov

Bakis

Lackey

et al.

FRP reinforcing bars – design and methods of manufacture (Review of patents). Mech Compos Mater 2013; 49: 381–400.

10.

Gangarao H, Liang R and Skidmore M. International workshop on aging of FRP composites for infrastructure held on 25–26 September 2013 at Ashburn, Virginia. Final Report, United Sates Department of Transportation – FHA – Washington-DC, 2014, p.41.

11.

Arrieta

Richaud

Fayollea

et al.

Thermal oxidation of vinyl ester and unsaturated polyester resins. Polymer Degrad Stabil 2016; 129: 142–155.

12.

Sarasini

Santulli

. Vinylester resins as a matrix material in advanced fibre-reinforced polymer (FRP) composites. J Civil Struct Eng 2013; 4: 69–87.

13.

Micelli

Nanni

. Durability of FRP rods for concrete structures. Construct Build Mater 2004; 18: 491–503.

14.

Robert

Cousin

Benmokrane

. Durability of GFRP reinforcing bars embedded in moist concrete. J Compos Constr 2009; 2: 66–73. Doi:10.1061/(ASCE)1090-0268(2009)13.

15.

Almusallam

Al-Salloum

Alsayed

et al.

Tensile properties of glass fiber-reinforced polymer bars embedded in concrete under severe laboratory and field environmental conditions. J Compos Mater 2013; 47: 393–407.

16.

Kim

Park

You

. Short-term durability test for GFRP rods under various environmental conditions. Compos Struct 2008; 83: 37–47.

17.

Ashbee

Wyatt

. Water damage in glass fibre/resin composites. Proc R Soc London Ser A 1969; 312: 553–564.

18.

Wei

Sun

Zhang

et al.

Effect of seawater exposure on compressive behavior of concrete columns reinforced longitudinally with glass fiber reinforced polymer bars. J Compos Mater 2017. https://doi.org/10.1177/0021998317742957 .

19.

Lee

Rockett

. Interactions of water with unsaturated polyester, vinyl ester and acrylic resins. Polymer 2017; 33: 3691–3697.

20.

Zhu

Leung

CKY

Kim

et al.

Tensile properties degradation of GFRP composites containing nanoclay in three different environments. J Compos Mater 2011; 46: 2179–2192.

21.

Marouani

Curtil

Hamelin

. Ageing of carbon/epoxy and carbon/vinylester composites used in the reinforcement and/or the repair of civil engineering structures. Compos Eng 2012; 43: 2020–2030.

22.

Wang

Zhang

et al.

Chemical durability and mechanical properties of alkali-proof basalt fiber and its reinforced epoxy composites. J Reinf Plast Compos 2008; 27: 393–407.

23.

Soles

Chang

Bolan

et al.

Contributions of the nanovoid structure to the moisture absorption properties of epoxy resins. J Polymer Sci Polymer Phys 1998; 36: 3035–3048.

24.

Benmokrane

Ali

Mohamed

et al.

Laboratory assessment and durability performance of vinyl-ester, polyester, and epoxy glass-FRP bars for concrete structures. Compos Eng 2017; 114: 163–174.

25.

Bank

. Composites for construction: structural design with FRP materials, Hoboken, NJ: Wiley, 2006. DOI: 10.1002/9780470121429.

26.

American Concrete Institute. Guide test methods for fiber-reinforced polymers (FRPs) for reinforcing or strengthening concrete structures. ACI 440.3R-04, Farmington Hills, MI, 2004.

27.

ASTM D7205. Standard test method for tensile properties of fiber reinforced polymer matrix composite bars. American Society for Testing and Materials, 2011.

28.

American Concrete Institute. Specification for carbon and glass fiber-reinforced polymer bar materials for concrete reinforcement. ACI 440.6 M-08, Farmington Hills, MI, 2008.

29.

Canadian Standards Association. Specification for fibre reinforced polymers. CAN/CSA S807-10, Rexdale, Ontario, Canada, 2010.

30.

Canadian Standards Association. Design and construction of building components with fibre-reinforced polymers. CAN/CSA S806-12, Rexdale, Ontario, Canada, 2012.

31.

ASTM. Standard test method for alkali resistance of fiber reinforced polymer (FRP) matrix composite bars used in concrete construction. ASTM D7705, West Conshohocken, PA, 2012.

32.

Kayati. CRAS: expansive cement, http://www.kayati.com (2014, accessed 16 May 2015).

33.

Nelson

. Accelerated testing – statistical models, test plans, and data analyses, New York, NY: Wiley, 1990.

34.

Bank

Gentry

Barkatt

. Accelerated test methods to determine the long-term behavior of FRP composite structures: environmental effects. J Reinf Plast Compos 1995; 14: 559–587.

35.

Robert

Benmokrane

. Combined effects of saline solution and moist concrete on long-term durability of GFRP reinforcing bars. Construct Build Mater 2013; 38: 274–284.

36.

Chen

Davalos

Ray

. Durability prediction for GFRP bars using short-term data of accelerated aging tests. J Compos Constr 2006; 10: 279–286.

37.

Panigrahi

. Microstructures and properties of low-alloy fire resistant steel. Bull Mater Sci 2006; 29: 59–66.

38.

IBM Corp. IBM SPSS Statistics for Windows. Version 23.0, Armonk, NY: IBM Corp, 2015.

39.

Bank

Gentry

Thompson

et al.

A model specification for composites for civil engineering structures. Construct Build Mater 2003; 17: 405–437.

40.

Huang

Aboutaha

. Environmental reduction factors for GFRP bars used as concrete reinforcement: new scientific approach. J Compos Constr 2010; 14: 479–486.

41.

Dejke V and Tepfers R. Durability and service life time prediction of GFRP for concrete reinforcement. In: Proc., 5th Int. Symp. on fiber reinforced polymers for reinforced concrete structures (FRPRCS-5), Vol. 2, Thomas Telford, Cambridge, UK, pp.505–513.