Complete nonlinear response of reinforced concrete beams under cyclic loading

Complete nonlinear analysis is carried out for cyclically loaded reinforced concrete (RC) beams made of normal‐ and high‐strength concrete. The loading stage covers not only the pre‐peak stage but also the post‐peak stage in particular. The analysis is based on a numerical method that employs the actual stress–strain curves and takes into account the stress‐path dependence of concrete and steel reinforcement. The complete nonlinear behavior of RC beams under both non‐reversed and reversed cyclic loading is studied based on the moment–curvature relationship obtained. Generally, the response under cyclic loading is found to be dependent on the loading path in bending. The variation of neutral axis depth is different for under‐ and over‐reinforced sections during cyclic loading. The Bauschinger effect of steel reinforcement is insignificant for non‐reversed cyclic loading but notable for reversed cyclic loading, especially when the loading extends into the post‐peak stage. The beneficial effects of concrete tension stiffening are only observed at the service stage and are more significant for under‐reinforced RC beams than over‐reinforced ones. Copyright © 2007 John Wiley & Sons, Ltd.