Experimental study on the seismic performance of a prefabricated steel column-column connection

An innovative prefabricated steel column-column connection composed of upper column, lower column, angles, friction device and posttensioned (PT) strands was proposed, in which seismic performance was mainly studied and theoretical analysis was carried out. This paper analyzed the influence of the axial compression ratio, the presence or absence of angle, and the thickness of angle on the failure model, hysteresis curves, skeleton curves, displacement ductility ratio and energy dissipation ability of the specimens. The test results demonstrated that initial stiffness and energy dissipation ability of the specimen increased by 15.1% and 8.6%, respectively, with an increase in the axial compression ratio by 0.11. The load-carrying capacity of the specimen with a 6 mm angle was always greater than that of the specimen without angle under the same loading displacement. The peak load and final cumulative energy dissipation of the specimen with a 6 mm angle increased by 16.3% and 28.7%, respectively, compared to that of the specimen without an angle. Increasing the thickness of the angle could effectively promote the load-carrying capacity and slow the later stiffness degradation and decrease the bucking deformation degree on the lower column flange of the specimen. However, when the thickness of angle is from 0 mm to 6 mm, from 6 mm to 10 mm, from 10 mm to 14 mm, the displacement ductility ratios of specimen is reduced by 21.8%, 11.7% and 39.8% respectively. In addition, an analytical bending capacity model of the connections was developed, which could reasonably predict the load-carrying capacity of the connections.