Numerical simulation of the seismic perofrmance of steel reinforced concrete columns with various confinement effect

For steel reinforced concrete (SRC) columns, concrete was confined by both the steel section and the reinforcement bars. The concrete section can be divided into three main zones, namely the strongly confined zone, partially confined zone, and unconfined concrete zone. A comprehensive stress-strain constitutive law for both unconfined and confined concrete was proposed based on the principle of confinement. Then the numerical model was developed by software ABAQUS, taking both effects of confinement on concrete and the interface interaction between the steel section into consideration. The finite element model has been validated by comparison with published experimental results. Numerical simulation with varied parameters including axial compression ration, shear span ratio and stirrup ratio was performed to reveal effects on the seismic performance of the composite columns.