Post-yield deformation parameters of reinforced concrete beam with corroded reinforcement

Abstract

This paper represents the post-yield behavior of reinforced concrete (RC) beams with corroded reinforcement. In order to assess the seismic suitability of existing structures, effect of corrosion in reinforcement on the behavior of various structural elements should be studied. Strong column weak beam behavior should occur in seismically efficient structure which ensures maximum plastic hinges to form in the beams. Plastic hinge parameters in RC beams should be clearly identified for repair and retrofitting of the old buildings and seismic analysis of new buildings too. As the concept of plastic hinges are extremely important in seismic analysis of existing RC structures which defines the deformation and load-carrying capacities of the RC beam. Sixteen simply supported beam types (three samples of each type) are tested with varying grade of concrete and type of reinforcement along with the condition of reinforcement (10, 20, and 30% corroded reinforcement) by applying two point loading (approximately one-third and two-third of span). Test results show that the RC beams with bars corroded to 30% have undesirable shear failure though have been designed to fail in flexure. The plastic hinge length (denoted as l p ) increases with the increase in concrete grade and decreases with the increase in yield strength of reinforcement. The increase in the corrosion percentage of reinforcement bars from 10 to 30% decreases the plastic hinge length, making it undesirable as a seismic member.