An innovative FRP fibre for concrete reinforcement: Production of fibre, micromechanics, and durability

An innovative FRP fibre is proposed for concrete reinforcement as an alternative to the corrosion-susceptible steel fibres and to fill in the performance gap in the polymer fibre reinforced concretes. Vacuum infusion technique was employed to produce glass- and carbon-fibre-reinforced FRP which was cut to produce FRP fibres with strengths ranging from 194 to 953 MPa. The interface between the FRP fibre and cementitious matrix was assessed by studying the reinforcing mechanisms and failure patters in single fibre pullout tests. The durability of the fibres was investigated in terms of changes in tensile- and bond strength following their exposure to an alkaline environment. Further, SEM images were also obtained to observe any morphological changes on the surface of the FRP fibres due to potential alkaline attacks. A greater pullout resistance of FRP fibres over traditional straight and some of the hooked steel fibres was observed. Overall, FRP fibres showed good alkaline resistance. While the GFRP fibre revealed small reductions in strength, the CFRP fibre showed no such decline. There was likewise no reduction in bond strength involving either of the types of fibre. In both cases, no morphological or chemical changes could be observed under the SEM-EDX either.