Experimental investigation of the stiffness of critical components in a moment-resisting composite connection

This paper discusses results of experiments on an element of a proposed moment-resisting composite connection. The element is subjected to cyclic tension. A feature of this element is the use of blind bolts and extensions to these bolts into the concrete-filled CHS column. The test specimens with extensions failed at a higher load and showed increased initial stiffness compared to the specimen without extensions. The experimentally derived values of initial stiffness are also compared to the initial stiffness values derived from a mechanical component model of the connection element.