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In order to improve the energy dissipation capacity and self-centering capacity of the frame structure, a functional self-centering beam-column joint based on superelastic SMA bar was proposed. In this paper, based on OpenSees finite element software platform, the finite element numerical model of self-centering SMA reinforced concrete beam-column joints was established by using SMA material self-centering double flag constitutive model, and the finite element simulation under low-cycle reciprocating action was carried out to obtain the hysteretic curve and skeleton curve of the joints. The validity of the joints analysis model is verified by comparing with the existing experimental results. The parameter analysis was carried out, and the parameters such as the quantity, length and yield strength of SMA material were considered respectively. The influence of SMA material parameters on the hysteretic performance and self-centering ability of the joints was analyzed. The results show that the superelastic SMA reinforced concrete beam-column joints have high energy dissipation capacity and self-centering capacity. The numerical analysis model can well simulate the hysteretic behavior of self-centering SMA joints under low cyclic reciprocating loads. The mechanical parameters of SMA bars have a great influence on the seismic performance of joints: under the condition of proper reinforcement, the larger the number of SMA configurations, the smaller the residual displacement and the stronger the centering capacity. Under the same condition, after the SMA bar exceeds the plastic hinge length, it has little effect on the joint performance. Under the condition of proper reinforcement, increasing the yield strength of SMA will improve the bearing capacity and selfcentering capacity of the joints.
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