Hysteretic model and numerical simulation method of T-shaped SRC column-steel beam joints

As the key member that connects the column and steel beam of steel-reinforced concrete (SRC) frame structures, the T-shaped SRC column-steel beam joints should have good hysteretic characteristics under earthquakes, which has an important influence on the safety and stability of the structures. To describe the degradation law of joints, a tri-linear skeleton curve model was developed to study the seismic characteristics of this type of joint based on the experimental results. An improved Bouc-Wen-Baber-Noori (BWBN) model was established for Tshaped steel SRC column-steel beam joints by combining the BWBN model and hysteresis characteristics. The parameters of the hysteresis model were obtained using a genetic algorithm and nonlinear regression analysis. Based on the Visual Studio platform, the improved BWBN model was embedded and developed in the OpenSees software, and a numerical simulation analysis was conducted to verify the accuracy of the numerical simulation method. The results show that the hysteresis curve obtained via the simulation is in good agreement with the test curve. The improved BWBN model effectively represents the actual degradation characteristics of this type of structural member under seismic loads.