Dynamic behavior of steel frames with beam flanges shaved around connection

The performance of welded beam-to-column connection has always been questioned. Brittle fractures of this type of beam-to-column connection have been reported from large connection tests, and also found after earthquakes such as the Northridge and Kobe earthquakes. It has been suggested that by trimming the beam flanges according to the moment profile, the ductility of the connection can be improved drastically. This paper describes experimental studies that have examined the dynamic characteristics of steel frames with beam flanges shaved compared with those of the traditional design. It was found that the frame with beam ranges shaved had superior behavior to the frame of conventional design. Brittle fracture occurred on the conventional frame at PGA (peak ground acceleration) 0.9 g of magnified El Centro earthquake, while the new design survived after excitation of PGA 1.2 g, and spread of plasticity was found in the pre-selected tapered zone. The energy dissipation capacity of the new design was found to be much larger than that of the traditional frame. (C) 1997 Elsevier Science Ltd.