This paper presents series of experimental studies on newly developed basalt fiber reinforced polymer (FRP) grids for the flexural strengthening of reinforced concrete beams. The study includes tensile behavior of the basalt FRP grids with three types of thickness, bonding behavior between the basalt FRP grids and the concrete with epoxy resin, and flexural behavior of the reinforced concrete beams strengthened with basalt FRP grids. The results revealed that the modulus of elasticity of the basalt FRP grids ranged between 40 and 43 GPa, and their tensile strength ranged between 815 and 931 MPa. The bond stress–slip behavior of the basalt FRP grids and concrete exhibited a ductile failure manner in comparison to that of FRP sheets and concrete; the bond strength of the tested basalt FRP grids was in the range of 3.26–6.06 MPa, and its slip at peak ranged between 0.15 and 0.4 mm. Beams strengthened with basalt FRP grids failed by crushing of compressive concrete or fiber reinforced polymer rupture and no debonding failure was observed for any of the tested beams.
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