A New Rigid Connection for Heavy Beams and Columns in Steel Moment Resisting Frames

The 1994 Northridge earthquake revealed the vulnerabilities of the prevalent welded moment connections in Special Moment Resisting Frames (SMRF) at the time. Since then, extensive research has been performed to identify problems that caused poor performance of pre-Northridge welded moment connections and to come up with new moment connection solutions that can satisfactorily withstand the test of major earthquakes. Most of these efforts, however, are concentrated around connections consisting of beams and columns of small to moderate sizes. This paper presents a new SMRF connection suitable for tall buildings as well as projects that require long beam spans and tall story heights for their SMRF systems. The proposed connection has passed analytical as well as full-scale experimental studies with 20 in. and 24 in. square box columns and W36-W40 beams. A total of three laboratory tests were conducted and all specimens withstood large plastic rotation without any sign of deterioration in stiffness or strength