Study of Bending Behavior of Reinforced Concrete Sections Under Cyclic Loads

Abstract

This paper is concerned with the bending behavior of reinforced concrete sections subjected to cyclic loads, such as wind loads or earthquake loads. Previous studies have indicated that the cyclic loading of such kind can cause failure in the joints of a structure which subsequently put the structure into the state of instability or collapse. The paper also pays attention to the behavior of reinforced concrete beams and frames. Modeling of the cyclic relationship between moment and curvature is presented for the reinforced concrete sections under effect of axial load and moment on the assumption of full bond between steel and concrete. The shear deformation however is sidestepped. The stiffness method with the effective secant stiffness is used in the analysis of the structures for calculating displacement in each section and then getting the load-displacement curves, moreover, the recurrence method is used in the analysis of simple members in structures like reinforced concrete beams subjected to cyclic loads. The current study presents a numerical model which is capable of predicting the behavior of a reinforced concrete beam, frame and joint subjected to cyclic loading. The effect of axial force on the structure is also considered. The study concludes that the effect of axial force in the structural members is to decrease the energy absorption by these members and increases their failure loads. It also shows that the model used in the analysis of reinforced concrete sections has a good accuracy, it has ability to decrease the time of computer running compared with other methods, this makes it possible to depend on the analysis .The stiffness and recurrence method show good activity in the analysis from the obtained results.