This paper presents an experimental study on the mechanical properties of the helically deformed glass fiber-reinforced polymer (GFRP) bars. The mechanical properties were determined through tensile, transverse shear, apparent horizontal shear, and pullout tests. The GFRP bars were manufactured using high resistant fiberglass embedded in a vinyl ester resin. The tested bars featured a helically deformed surface. Two bar sizes (#4 and #7) are selected in this investigation. The tensile properties of the GFRP bars met the Grade III classification in the CSA S807-19 specification, based on modulus of elasticity greater than 60 GPa. The bond between the GFRP bar and concrete is considered a critical factor that influences the structure’s behavior. The results showed that the bond strength of the tested GFRP bars was above the minimum requirements in CSA S807-19. Additionally, the tested GFRP bars satisfied the minimum limits of transverse shear, and horizontal shear strength as per CSA S807-19. Furthermore, the paper discusses the practical application of GFRP in concrete-face rockfill dam and other projects.