Comparative post-yield performance evaluation of flexure member with corroded reinforcement

Abstract

Existing plastic hinge models for reinforced concrete beams do not consider the effect of reinforcement corrosion. This paper represents the plastic hinge model of corroded Reinforced Concrete (RC) beams tested experimentally as well as investigated analytically through nonlinear finite element modeling. An attempt is then made to arrive at simple empirical equation for maximum moment including the percentage of corrosion, using soft computing technique of Genetic Programming (GP). Simply supported beams are analysed with varying grades of concrete and type of reinforcement along with the condition of reinforcement by applying two-point loading (approximately 1/3rd and 2/3rd of span) and verified with the experiments performed. Test results show that the model can accurately predict the force deflection response and failure mode. The results show decrease in the moment and rotation capacity with the increase in corrosion percentage of reinforcement bars used in RC beams. The equation obtained as an output of GP models indicates the influence of yield strength of reinforcement, concrete grade and percentage of corrosion of RC beam over maximum moment carrying capacity.