Experimental Studies on Cyclic Performance of Column Base Strong Axis-Aligned Asymmetric Friction Connections

This paper describes experimental testing of an asymmetric friction connection (AFC) at the base of a steel column such as may be used in a moment-frame. Friction/sliding surfaces were parallel to the column-strong axis. In-plane, out-of-plane and 2D clover leaf-cyclic tests were conducted of columns both with and without applied axial force. Tests were conducted both with and without bolts passing through the plates to provide compression on the sliding/friction interface. It was found that this type of rocking base-friction connection can tolerate high levels of drift without significant strength degradation, although some stiffness degradation occurred, especially after the cycles in the weak-axis direction. A simple procedure proposed to estimate the moment resistance is verified. The friction-base connections, having similar cost to conventional connections and exhibiting low-damage performance, have the potential to become widely used in aseismic construction. (C) 2015 American Society of Civil Engineers.