Experimental Analyses of Mechanical Performance of CFST Column to Assembled Steel H-Beam Connections

The mechanical performance of a new proposed type of cross-shaped connection with concrete-filled steel tubular (CFST) column and assembled steel H-beam was investigated. Cyclic loading tests on the cross-shaped connections are carried out by using MTS servo loading system. Comparative analyses are conducted based on the experimental results including hysteretic curves, skeleton curves and stiffness degradation curves as well as ductility coefficients of cyclic loading tests. Furthermore, effects of geometric parameters of ring-stiffened plate, axial compression ratio and backing plate on the deformation performance of cross-shaped connections are analyzed. The results show that the increase of width of ring plate and the shape change of ring plate from square to circle can both significantly improve the ductility and the hysteretic characteristics of connection. It is emphasized that the specimen with square ring plates is of better deformation performance but lower bearing capacity than the ones with circular ring plates. Besides, the backing plates always have positive effects on the hysteretic characteristics, ductility and energy dissipation of the CFST column connections. Conversely, the increase of axial compression ratio contributes negatively to both the bearing capacity and deformation performance of the connection specimens. It can be concluded that the presented cross-shaped connection is of good deformation performance relating to hysteretic characteristics, energy dissipation and ductility, which can provide reference towards engineering practice with potential perspective application.