Development of near-fault loading protocols for first-story steel columns in dual systems with BRBs

ABSTRACTThe AISC 341–16 (2016) has loading protocols for beam-to-column moment connections and buckling-restrained braces, but it does not have a loading protocol for columns. Because a first-story column base is expected to form a plastic hinge in a building, a loading protocol for first-story columns in a dual system that comprises moment-resisting frames and buckling-restrained braced frames under varied axial force and lateral drift is required. Moreover, the symmetric cyclic loading protocols of AISC 341 do not include the effect of near-fault earthquakes, which is common in Taiwan. Therefore, the effect of near-fault earthquakes on first-story columns must be considered during the development of a loading protocol for dual systems. In the present study, four dual systems (representing 3-story, 7-story, 15-story, and 25-story frames) are subjected to 11 near-fault earthquake motions, used for developing near-fault loading protocols of first-story columns for the lateral drift and axial load responses.