Numerical simulation of the hysteretic performance of exterior reinforced concrete beam-column joints

In order to accurately simulate the hysteretic response of exterior beam-column joints under seismic conditions element model of exterior beam-column joints that took the bond degradation mechanism into account is established. Based on the ANSYS finite element platform, the Voce-Chaboche combined hardening model is used to define the cyclic constitutive relationship of reinforcement, and the composite spring elements are developed to simulate the bond degradation mechanism between steel bar and concrete under reciprocating loading. A prediction model for the bond-slip constitutive relationship under reciprocating loading is proposed based on damage theory. The hysteresis curves, skeleton curves, stiffness degradation curves and stress nephogram obtained from the finite element calculation are compared with the experimental results. The comparison shows that the combined hardening constitutive model can better describe the hysteretic response of steel bars under reciprocating loads. Composite spring elements successfully invert the bond degradation characteristics between steel bars and concrete under reciprocating loads. The development of plastic hinges in the joint beam under reciprocating loads leads to plastic elongation of the beam, which will adversely affect the exterior column. The numerical simulation results are in good agreement with the experimental results, providing an important theoretical basis and technical platform for accurately simulating the hysteretic performance of exterior beam-column joints. © 2024 Harbin Institute of Technology. All rights reserved.