Shear Capacity of Reinforced Concrete Beam with Diagonal Reinforcement Based on Modified Compression Field Theory

Abstract

For the compression—shear failure of a reinforced concrete bridge beam with diagonal reinforcement, the calculation of ultimate shear capacity is proposed based on the modified compression field theory (MCFT). Shear force is shared by the shear compression zone of concrete, stirrups, and diagonal reinforcements intersecting with diagonal cracks. The shear capacities of concrete in the tensile and compression areas are calculated. The new balance equation between the average stress and the internal force of cracked concrete is established, and the effects of diagonal reinforcement on the stress of diagonal cracks are considered. This procedure considers the constitutive relation conditions of materials and the deformation compatibility of concrete. The theoretical shear capacity predicted by MCFT is validated by the test results of two reinforced concrete beams, providing a reference for calculating the capacity of reinforced concrete beam.