Abstract：The hybrid reinforced concrete (Hybrid-RC) beams with the combination of new fiber composite materials and steel bars of BFRP(Basalt fiber-reinforced polymer) and SFCB(steel-FRP composite bar） are often reinforced with asymmetric reinforcement, which may leads to excessive crack width in the structure. To solve the problem, seven concrete beams were designed. The crack behavior of Hybrid-RC beam with asymmetric reinforcement was investigated.The experimental results show that the equivalent reinforcement ratio of ρe and the axial tensile strength ratio of γ between reinforcement and FRP bars have great influence on the crack width of Hybrid-RC beam. For the calculation of the crack width of Hybrid-RC beams, the recommended values of the bond-quality coefficient of kb using the American Concrete Institute (ACI) code and the Canadian Standard Association (CSA) code are given respectively.
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2021, Vol. 42 
