Implementation of multi-walled carbon nanotube incorporated GFRP as an alternative for CFRP in strengthening of concrete cylinders

Carbon fibre is the most widely utilized fibre for strengthening and retrofitting applications in the construction sector. The high cost of carbon fibre necessitates the identification of an alternative system for the retrofitting and repairing of concrete structures. In the current study, the characteristics of Glass Fibre Reinforced Polymer (GFRP), Carbon Fibre Reinforced Polymer (CFRP), and Multi-Walled Carbon Nanotube (MWCNT) incorporated GRFP are assessed with epoxy as a matrix for concrete cylinder confinement. The evaluation of one and two-layer CFRP confinement on concrete cylinders is carried out and outcomes are compared with the three-layer MWCNT incorporated GFRP confinement. A significant increase was observed in the axial compressive load-bearing capability of specimens with 1 wt percentage (wt%) MWCNT incorporated GFRP confined concrete cylinders. The axial load-carrying capability of concrete specimens with one layer of CFRP confinement was equivalent to that of specimens with 1 wt% MWCNT incorporated three-layer GFRP confinement. The axial strain of MWCNT incorporated three-layer GFRP confined specimens was 75 % more than one-layer and 12 % higher than two-layer CFRP confined specimens. According to observations, MWCNT-incorporated FRP confinement improves the energy absorption and ductility index. Ultrasonic pulse velocity test results confirmed the potency of three-layer GFRP confinement as a replacement for one and two layers of CFRP. A cost analysis is also carried out to validate the economic viability of the MWCNT-based GFRP compared to CFRP confinement.