LOAD-DEFORMATION ANALYSIS OF REINFORCED CONCRETE COLUMNS CONSIDERING AXIAL-FLEXURE-SHEAR INTERACTION

In order to study the load-bearing and performance of reinforced concrete columns with different failure modes, a load-deformation analysis model for reinforced concrete columns is proposed, considering the axial-shear-flexure interaction. Based on the modified compression field theory and the traditional fiber section analysis method, the whole loading process of the column is divided into two stages, i.e., bending-control stage and shear-control stage. The tension and compression zones of the control section are analyzed separately, considering the effect of compressive buckling of longitudinal reinforcement and the P-Δ effect, then the shear capacity and lateral deformation of the column are obtained. Finally, the collected pseudo-static test columns are simulated to verify the effectiveness of the proposed model. The results show that the reinforced concrete columns under axial-shear-flexure interaction will fail in three failure modes including flexural failure, flexural-shear failure and shear failure, the load-deformation performance of which varies greatly. The calculated curves obtained by the proposed model are in a good agreement with experimental results, so that the proposed model can be applied to analyze the aseismic performance of reinforced concrete columns.