Flexural behaviour of CFRP RC beams having a ductile cementitious composite layer in compression zone: an analytical study

Today, the use of fibre reinforced polymer (FRP) bars has received considerable attention. However, concrete beams reinforced with FRP bars suffer from a lack of ductility. The addition of steel bars to the beams has been widely studied to improve ductility. In this study, the idea of using a ductile cementitious composite layer (DCCL) in the compression zone is investigated. In fact, the ductility of DCCL comes from the bridging action of fibres and confinement concepts rather than the yielding of steel members. First, an analytical model is proposed to predict the behaviour of the beams. Then, the behaviour of concrete beams reinforced with FRP bars having various DCCL layers is investigated. It is shown that using DCCL can improve the ductility of the beams. The ductility ratio of the beam with a layer of DCCL is 3.5 times more than that of the control beam.