Experimental Study on Beam-to-Column Connections of Steel Frame Structures with Steel Slit Dampers

After the Northridge and Kobe earthquakes important experimental programs on beam-to-column connections were developed because of brittle fractures at welded beam-to-column connections. A number of studies are being carried out on a variety of materials and systems that dissipate the seismic loading effects in order to improve the seismic performance of steel frames. In the research reported in this paper, a slit steel damper system was developed to prevent the damage formation of standard columns and beams by dissipating lateral loads at the beam-to-column connections of steel frames. Therefore, the columns and beams of steel frames will not be damaged after a heavy earthquake, and the structures might be put into the service again simply by replacing the dampers at the connection sites. The seismic performance of the studied connection was verified through cyclic tests of two full-scale steel frames that had slit dampers and of one specimen that had a conventional extended end-plate connection. Test results indicated that the proposed connection showed a good hysteretic behavior, a good energy dissipation capacity, and good rigidity. However, plastic deformation is limited to the slit dampers, while the inelastic behavior of the beams and columns is prevented. (C) 2014 American Society of Civil Engineers.