Numerical study on seismic performance of a novel self-centering steel-concrete composite joint

Based on the design concept of post-earthquake resilience, a new self-centering steel-concrete composite joint is proposed. In this paper, five interior joint models are designed to analyze the effect of initial prestress and the diameter of energy-dissipating steel rods on the seismic performance by ABAQUS finite element software. The results show that reasonable control of magnitude of initial prestress and the diameter of energy-dissipating steel rods can realize the function of post-earthquake resilience by replacing the energy-dissipating plates. The joints exhibit stable and full hysteresis loops, the ductility coefficients are all above 3.0, indicating it has good energy dissipation capacity and ductility. Increasing initial prestress can improve the bearing capacity, initial stiffness and self-centering capacity, however the energy dissipation capacity and ductility will experience a certain degree of reduction. Increasing the diameter of energy-dissipating steel rods can improve the bearing capacity and initial stiffness, however the self-centering capacity and ductility will experience a certain degree of reduction. Finally, the flexural capacity formula of the joint is proposed, and the calculation results of the formula are in good agreement with the finite element analysis and experimental results.