Improved Link-to-Column Connections for Steel Eccentrically Braced Frames

Abstract

Link-to-column connections in steel eccentrically braced frames must be capable of sustaining large cyclic forces and inelastic rotations. United States code provisions require that satisfactory performance of link-to-column connections be verified by testing under a prescribed loading protocol. However, there are few link-to-column connection details that have satisfied these testing criteria. This paper describes a pilot investigation of two promising link-to-column connection details, as follows: (1) the fillet welded connection, which uses fillet welds or a combination of fillet and groove welds between the link and the column flange; and (2) the supplemental web doubler connection, which reinforces the connection region using a pair of doubler plates in the first link web panel next to the column, parallel to but offset from the link web. These two details showed excellent performance in a series of eight tests. This paper describes these link-to-column connection details, summarizes the results of cyclic loading tests, and discusses design issues and approaches for these connections.