Evaluation of the Energy Dissipation Capacities of Beam-to-Column Moment Connections for Steel Frames

Before the occurrence of the Northridge earthquake in the United States and the southern Hyogo prefecture earthquake in Japan, beam-to-column moment connections for structural steel buildings were considered to have sufficient strength, stiffness, and energy dissipation capacities. Some of the beam-to-column moment connections demonstrated insufficient strength and energy dissipation capacities however, and suffered brittle failure when the Northridge and southern Hyogo prefecture earthquakes hit. In South Korea, the use of beam-to-column moment connections, which are pre-qualified by some authorized architectural institutes, is strictly regulated by the Korean Building Code. In addition, the beam-to-column moment connections, which are summarized in the Standard Connection Detailing Guides published by the Korean Society of Steel Construction, can be recommended only for the application of structural steel buildings. The number of such recommended seismic resisting moment connections is limited, however, for the application of structural steel buildings. Therefore, this research was conducted to evaluate the flexural design strength and energy dissipation capacity of five connection types, and to examine their practical applicability for structural steel buildings in South Korea. Towards this end, three-dimensional nonlinear finite element analysis was conducted with respect to each of the beam-to-column moment connections.