Seismic behavior of high-strength concrete columns reinforced with CFRP tendons and high-strength steels

In order to investigate the seismic performance of high-strength concrete columns reinforced with carbon fiber reinforced polymer (CFPR) and high-strength steel, hybrid reinforced concrete columns with CFRP tendons and high-strength steels and two high-strength reinforced concrete columns were prepared and tested. The experimental and numerical results were used to explore the factors influencing the seismic performance of high strength concrete columns, including the bonding condition of CFRP tendons, axial compression ratio and concrete type. The results show that all high-strength concrete columns with CFRP tendons and high-strength steel have ductile failure. The concrete columns with steel fiber or reactive powder concrete (RPC) exhibit good ductility and energy dissipation under the same condition. The deformation and bearing capacity of the high-strength concrete column with bonded CFRP tendons are 9.6% and 17.1% higher than that of unbonded hybrid reinforced concrete columns, but the ductility coefficient is lower than 22.5%. Under ductile failure conditions, as the axial pressure ratio increases, the bearing capacity of high-strength concrete columns is improved significantly, but the energy dissipation capacity and plastic deformation capacity decrease obviously. The higher ratio of high-strength steels and CFRP tendons, the ultimate bearing capacities and deformation capacities of high-strength hybrid reinforcement columns are higher. © 2021, Editorial Office of Acta Materiae Compositae Sinica. All right reserved.