Cure ratio is a key property for the acceptance and use of glass fiber reinforced polymer bars in civil engineering infrastructure. Yet, there have been no reported studies investigating the effect of cure ratio on the physical, thermal, and mechanical properties of the fiber reinforced polymer bars. This paper presents an interlaboratory test program involving four laboratories to evaluate the cure ratio and glass transition temperature of glass fiber reinforced polymer bars from different production lots. The effect of cure ratio on the physical, mechanical, and microstructure of the glass fiber reinforced polymer bars was also evaluated. The results of this study show that the cure ratio significantly affected the glass transition temperature (Tg) of the glass fiber reinforced polymer bars tested. The results also show that interlaminar shear strength of the glass fiber reinforced polymer bars was affected by the cure ratio but not the physical and tensile properties, microstructure, or chemical composition. The fully cured glass fiber reinforced polymer bars had interlaminar shear strength up to 8% higher than the partially cured bars. Nonetheless, the glass fiber reinforced polymer bars with a cure ratio of only 96% still had properties well above the minimum prescribed physical and mechanical properties for the reinforcing materials in concrete structures.
BenmokraneBEl-SalakawyEEl-RagabyAet al.Designing and testing of concrete bridge decks reinforced with glass FRP bars. J Bridge Eng2006; 11: 217–229.
2.
ManaloACBenmokraneBParkKet al.Recent developments on FRP bars as internal reinforcement in concrete structures. Concr Aust2014; 40: 46–56.
3.
Gentry R, Bakis C, Harries K, et al. Development of ASTM test methods for FRP composite materials: Overview and transverse shear. In: Proceedings of the 6th international conference on FRP composites in civil engineering (CICE 2012), Rome, Italy, 13-15 June 2012, paper 12-513, p. 8.
4.
MarananGBManaloACBenmokraneBet al.Evaluation of the flexural strength and serviceability of geopolymer concrete beams reinforced with glass-fibre-reinforced polymer (GFRP) bars. Eng Struct2015; 101: 529–541.
5.
MarananGBManaloACBenmokraneBet al.Behavior of concentrically loaded geopolymer concrete columns reinforced longitudinally and transversely with GFRP bars. Eng Struct2016; 117: 422–436.
6.
BouguerraKAhmedEAEl-GamalSet al.Testing of full-scale concrete bridge deck slabs reinforced with fibre-reinforced polymer (FRP) bars. Constr Build Mater2011; 25: 3956–3965.
7.
Benmokrane B, El-Salakawy EF, Desgagné G and Lackey T. Building a New Generation of Concrete Bridge Decks using FRP Bars. Concrete International, the ACI Magazine 2004; 26: 84–90.
8.
Benmokrane B, Ahmed E, Dulude C and Boucher E. Design, construction, and monitoring of the first worldwide two-way flat slab parking garage reinforced with GFRP bars. Proc., 6th Int. Conf. on FRP Composites in Civil Engineering, Kingston, ON, Canada: International Institute for FRP in Construction, 2012.
9.
Mohamed HM and Benmokrane B. Design and Performance of Reinforced Concrete Water Chlorination Tank Totally Reinforced with GFRP Bars: Case Study, Journal of Composite for Construction 2014; 10.1061/(ASCE)CC.1943-5614.0000429, 05013001–105013001-11.
10.
El-Salakawy EF, Benmokrane B and Brière F. Glass FRP composite bars for concrete bridge barriers. Journal of Science and Engineering of Composite Materials 2005; 12: 167–192.
11.
Benmokrane B, Eisa M, El-Gamal S, Thébeau, D and El-Salakawy E. Pavement System Suiting Local Conditions: Québec Studies Continuously Reinforced Concrete Pavement with Glass Fiber-Reinforced Polymer Bars. Journal of American Concrete Institute 2008; 30: 34–39.
12.
American Concrete Institute. Metric specification for carbon & glass fiber-reinforced polymer bar materials for concrete reinforcement. ACI-440.6M-08. Farmington Hills, MI: ACI, 2008.
13.
Canadian Standards Association (CSA). Specification for fibre-reinforced polymers. CAN/CSA-S807. Rexdale, ON: CSA, 2015.
14.
ASTM Standard D7957-17. Standard specification for solid round glass fiber reinforced polymer bars for concrete reinforcement. ASTM D570 – 98. West Conshohocken, PA: ASTM International, 2017.
15.
BaninayatPPatnaikA. Variability of mechanical properties of basalt fiber reinforced polymer bars manufactured by wet-layup method. Mater Des2014; 56: 898–906.
16.
BenmokraneBNazairCSeynaveXet al.Comparison between ASTM D7205 and CSA S806 tensile-testing methods for glass-fiber-reinforced polymer (GFRP) bars. ASCE J Compos Constr2017; 21: 1–13.
17.
ASTM Standard D883-12. Standard terminology relating to plastics. West Conshohocken, PA: ASTM International, 2012.
18.
BankLCGentryTRThompsonBPet al.A model specification for FRP composites for civil engineering structures. Constr Build Mater2003; 17: 405–437.
19.
KumarDSShuklaMJMahatoKKet al.Effect of post-curing on thermal and mechanical behavior of GFRP composites. Mater Sci Eng2015; 75: 1–6.
20.
Hollaway LC. Key issues in the use of fibre reinforced polymer (FRP) composites in the rehabilitation and retrofitting of concrete structure. In: Karbhari VM and Lee LS (eds) Service life estimation and extension of civil engineering structures. Cambridge, UK: Woodhead Publishing Ltd., pp. 3–74.
21.
LabroniciMIshidaH. Effect of degree of cure and fiber content on the mechanical and dynamic mechanical properties of carbon fiber reinforced PMR-15 polyimide composites. Polym Compos1999; 20: 515–523.
22.
ASTM Standard D3171-15. Standard test methods for constituent content of composite materials. West Conshohocken, PA: ASTM International, 2015.
ASTM Standard D570-98. Standard test method for water absorption of plastics. West Conshohocken, PA: ASTM International, 2010.
25.
Tannous FE and Saadatmanesh H. Durability of AR glass fiber reinforced plastic bars. Journal of Composite for Construction 1999; 3: 12–19.
26.
ASTM Standard D4475-02. Standard test method for apparent horizontal shear strength of pultruded reinforced plastic rods by the short-beam method. ASTM D4475-02, ASTM International, 2016. West Conshohocken, Philadelphia, Pa 19103.
27.
ASTM Standard D7205 / D7205M-06. Standard test method for tensile properties of fiber reinforced polymer matrix composite bars. West Conshohocken, PA: ASTM International, 2011.
28.
BankLC. Composites for construction: Structural design with FRP materials, Hoboken, NJ: Wiley and Sons, Inc., 2006.
29.
Maranan GB, Manalo AC, Karunasena W, et al. Flexural behaviour of glass fibre reinforced polymer (GFRP) bars subjected to elevated temperature. In: Proceedings of 23rd Australasian conference on the mechanics of structures and materials (ACMSM23), Byron Bay, Australia, 2014, pp. 187–192.
30.
HeJLiuWHuangYX. Simultaneous determination of glass transition temperatures of several polymers. PLoS One2016; 11: e0151454–e0151454. https://doi.org/10.1371/journal.pone.0151454.
31.
GopalAKAdaliSVerijenkoVE. Optimal temperature profiles for minimum residual stress in the cure process of polymer composites. Compos Struct2000; 48: 99–106.
32.
ZiaeeSPalmeseGR. Effects of temperature on cure kinetics and mechanical properties of vinyl ester resins. J Polym Sci B: Polym Phys1999; 37: 725–744.
33.
ZhangJXuYCHuangP. Effect of cure cycle on curing process and hardness for epoxy resin. Express Polym Lett2009; 3: 534–541.
34.
HernandezSSketFMolina-AldareguiJMet al.Effects of curing cycle on the void distribution and interlaminar shear strength in polymer-matrix composites. Compos Sci Technol2011; 71: 1331–1341.
35.
DaviesLWDayRJBondDet al.Effect of cure cycle heat transfer rates on the physical and mechanical properties of an epoxy matric composites. Compos Sci Technol2007; 67: 1892–1899.
36.
ASTM Standard E1356-08. Standard test method for assignment of the glass transition temperatures by differential scanning calorimetry. West Conshohocken, PA: ASTM International, 2014.
37.
ASTM Standard E1131-08. Standard test method for compositional analysis by thermogravimetry. West Conshohocken, PA: ASTM International, 2014.
