Experimental investigation of dogbone moment connections

A test program was conducted on seismic-resistant steel moment connections constructed using a Reduced Beam Section, also known as a "dogbone." In the dogbone connection, portions of the beam flange near the beam-to-column co nnection are trimmed in order to enhance ductility under severe cyclic load s. This test program was conducted in order to evaluate the dogbone connect ion for use in a 25 story steel office building in Salt Lake City. A total of five large scale specimens were tested in this program, with bea m sizes ranging from W30x148 up to W36x194. The specimens combined the dogb one cutout in the beam flanges with an all welded beam-to-column connection constructed using improved welding practices. The test program showed exce llent performance for specimens constructed with a circular radius cut dogb one. Cost comparisons indicated that this connection also provided good eco nomy compared to other alternatives considered for this building constructi on project. Overall, the dogbone appears to be one of the more promising mo ment connection details for use in seismic-resistant steel moment frames. This paper summarizes the results of the experimental program, and provides suggestions for the design of dogbone moment connections.