Shear performance and capacity of FRP reinforced concrete beams: Comprehensive review and design evaluation

Abstract

To enhance the durability of concrete structures in harsh environments, replacing steel bars with FRP bars is judged a feasible method. The low elastic modulus and transverse strength of FRP bars result in the weak shear capacity of concrete beams reinforced with FRP bars. Reviewing and summarizing existing literature are important for addressing this challenge. The research progress on the shear behaviour of concrete beams reinforced with FRP bars was systematically described from two aspects in this paper. In the aspect of literature review, shear mechanisms and main influencing factors of concrete and FRP stirrups were summarized. In addition, achievements and shortcomings of existing literature were summarized, and potential research directions were pointed out. In the aspect of design method evaluation, a database containing 525 samples was established and calculation models of shear capacity of concrete beams reinforced with FRP bars in seven codes were evaluated. Evaluation parameters mainly included shear span ratio, effective height, and maximum strain of FRP stirrups. Based on the calculation model in Italian code CNR DT203-06, an optimized model was proposed to improve the accuracy in predicting concrete shear contribution. The review and evaluation in this paper had important reference significance for improving the design level of concrete structures reinforced with FRP bars and promoting the engineering application of FRP bars.