Experimental investigation of built-in replaceable links in external diaphragm connection between steel -beam and CHS column

Abstract

This paper investigates experimentally the cyclic behaviour of an external diaphragm connection between steel I-beam and circular hollow section column. The proposed joint includes two diaphragm plates welded to the outer circumference of the column and bolted to the beam flanges with two tapered cover plates. The cover plates were integrated in the connection to act as replaceable links after seismic actions. A series of full-scale laboratory experiments of the joint was conducted to investigate its energy dissipation and hysteretic response. The cover plates used in the experimental work had the same geometry but differed from each other on steel grade, bolt-holes size, use of stiffeners and bolts’ preloading force. The results confirmed that the main energy dissipation fuse in these connections was yielding in the reduced section areas of the cover plates. Connection slip created a second fuse of energy dissipation when bolts preloading force was properly controlled.