A design detail of beam-to-column connections is developed for previously proposed built-up column member comprising high-strength H-SA700 steel connecting to conventional-steel beams. In the design concept, the beams are allowed to develop plasticity during the large earthquakes, while the built-up column remains elastic. A bolted connection detail, consisting of steel end plates and high tension bolts, is adapted to connect the beams to the joints. Experiments were conducted to examine the seismic performance of the beam-to-column connections with the built-up column. Test results show that additional T-shape stiffeners were needed at the beam-to-column connections to provide appropriate rigidity of the joint to ensure the yielding of the beams.
