Flexural and shear hysteretic behaviour of reinforced concrete columns with variable axial load

The importance of non-linear biaxial models that are applicable to the analysis of reinforced concrete members under cyclic and dynamic loads has been recognized. Variations in the axially applied force can influence strength, stiffness and deformation capacity of such members. In this study, an inelastic biaxial model based on plasticity theory, is proposed. This quadri-linear degrading model takes into account the effect of axial load variation on lateral deformation. The model predictions are examined against available experimental results. Using the developed model, the effect of various axial loading patterns on the lateral deformation of reinforced concrete columns is investigated.