Shear Strength of FRP RC Beams and One-Way Slabs without Stirrups

Due to the complex mechanism of shear behavior, most current empirical methods do not physically simulate the shear behavior as seen in practice. These approaches, therefore, cannot be directly applied to accommodate advanced technologies such as in the use of fiber-reinforced polymer (FRP) or fiber-reinforced concrete. With FRP reinforcement widely used nowadays, there is a need for a mechanics-based approach to explain and simulate the shear failure mechanism. In this paper and from a mechanics-based segmental approach, a generic closed-form solution is derived for quantifying the shear capacity of RC beams and one-way slabs without stirrups and in theory with any type of reinforcement and concrete. The model is validated with 209 published shear tests of FRP-reinforced specimens with normal concrete and, to show the generic nature of the model, with a further 626 published shear tests on beams with steel reinforcement. The generic closed-form solution is further simplified to facilitate shear design. A comparison to the predictions made by design recommendations shows a reduction to different degrees in both mean and scatter of the measured-to-predicted shear strength ratio for the proposed approaches. (C) 2014 American Society of Civil Engineers.