Shear behaviour of panel zone in through-diaphragm connections to steel tubular columns

This paper experimentally, numerically, and analytically, studied the seismic behaviour of through-diaphragm connections in the steel framed structure. Three through-diaphragm connections between steel tubular column and H-shaped steel beam were tested under cyclic loading to investigate the seismic behaviours of the panel zones. The studied parameters included different configurations of the connections (interior and exterior connections) and thickness of the tube in the panel zone of connections. The failure modes, load-displacement behaviours, ductility and strength degradation of these tested specimens were analysed and discussed. Nonlinear finite element models (FEMs) were developed to simulate the seismic behaviour of these connections. The developed FEMs considered the geometric and material nonlinearities of the connections. The validations of the FE predictions against the test results confirmed the accuracy of the FEM in predicting the seismic behaviour of the connections. With these validated FE models, a subsequent parametric study comprising 15 cases were performed to investigate the influence of thickness of tube web and flange in the panel zone on the shear behaviour of the connections. Finally, the analytical model was also developed to predict the shear resistance of panel zone. The accuracy of this analytical model was validated by the reported test results.