Simplified Shear Design of Slender Reinforced Concrete Beams with Stirrups

Abstract

For simplified shear design of slender reinforced concrete (RC) beams with stirrups, a modified variable-angle truss model is developed in this paper. In this model, an analytical solution of the inclination of struts (θ) is derived by combining the theory of plasticity and the concrete softening of the modified compression field theory (MCFT). It is found that there is a decreasing linear relationship between cotθ and lnω, where lnω is the natural logarithm of the mechanical shear-reinforcement ratio. On this basis, a new shear design equation is proposed for slender RC beams with stirrups, which is shown to be not only simpler, but to also provide improved prediction compared with the shear design provisions of some of the existing codes.