Experimental Study of Large Seismic Steel Beam-to-Column Connections

Abstract

ABSTRACT Two large bolted steel moment-resisting connections were studied by experiments. Theseconnections were single-sided beam-column assemblies that are representative of exteriorbeam-column connections. They were composed of W36x150 Grade 50 beams andW14x257 Grade 50 columns. T-sections were cut from W40x264 sections of Grade 50steel. The T-section webs were welded to the beams and prestressed by bolts to the beamflanges in the shop. Final beam-to-column assembly required no additional welding: theT-section flanges were bolted to the column and the column shear tab was bolted to thebeam web. The specimens had two symmetrically located T-sections with different webgeometry: Specimen 1 had rectangular-shaped webs, whereas Specimen 2 had U-shapedwebs. During cyclic testing beam deformation was minimal due to active participation ofthe T-section flanges: a separation between T-section flanges and the column flanges wasobserved. This separation occurred due to bending plastic deformation in the T-sectionflanges. This phenomenon allowed dissipating energy and prevented severe buckling inthe beam flanges and beam web.