An Experimental and Numerical Investigation on Seismic Retrofit of Steel Moment Frame Connections

A series of five large-scale steel moment frame connections containing one reference and four retrofitted connections were tested under cyclic loads. The retrofit techniques focused on the beam bottom flange in which a “ductile fuse” was defined through “drilling” and “heat induction”. It was concluded that “drilling” of the beam would increase the connection sensitivity to out of plane buckling. A considerable advantage of “heat induction” technique was low stress demands in near weld region. Meanwhile, as the beam was heated with no material removal, the out of plane buckling resistance was similar to that of the reference specimen.