Shear behavior of FRP-UHPC tubular beams

Fiber reinforced polymer (FRP) reinfrocement has been proposed to be reinforcement in ultra-high performance concrete (UHPC) so as to avoid the post-peak strain softening behavior of UHPC under tension and to reduce the fiber dosage used in UHPC. In this paper, tubular beams made by FRP grid-reinforced UHPC composites (referred to as FRP-UHPC compoistes or simply FUC) have been proposed and ten FUC tubular beams were tested under shear loading. Effects of the shear span ratio, the fiber type (polyethylene (PE) fibers and steel fibers) on the shear behavior of FUC tubular beams were investigated. Results reveal that the proposed FUC tubular beams have an excellent ultimate strength and a ductile behavior under shear. A theoretical model based on the truss-arch theory is proposed for predicting the shear capacity FUC tubular beams, and its accuracy is verified against the test results.