Abstract： In order to investigate the seismic behavior of high-strength concrete columns with HRB600 steel bars, cyclic loading tests on nine high-strength concrete columns reinforced with HRB400 and HRB600 steel bars were carried out under practical axial compression ratio. The main design parameters of specimens were steel grade, stirrup spacing, concrete strength and axial compression ratio. The failure modes, hysteretic properties, load-carrying capacity, ductility, stiffness degradation and energy dissipation capacity of specimens were analyzed and compared. Based on the test results, a restoring force model of high-strength concrete column with HRB600 steel bars was established. The research results indicate that the specimens have similar failure modes, which appear to be ductile bending failure with plastic hinge occurring at column bottom, local buckling of longitudinal reinforcement and spalling of concrete cover. It is shown that the high-strength concrete columns with HRB600 steel bars possess good hysteretic behavior, deformability and energy dissipation capacity as well as the seismic resilience. In the design of high-strength concrete columns, the conjunction of HRB600 steel bars and C80 grade concrete has good application performance. With reasonable design of stirrups, the ductility ratio of the high-strength concrete columns with HRB600 steel bars under a high axial compression ratio can be greater than 4.0. The restoring force model established from full-scale specimen tests has satisfactory calculation accuracy, which can be used for seismic elastic-plastic analysis of related engineering structures.
