Effects of detailing on panel zone seismic behaviour in special moment resisting frames with unequal beam depths

Abstract

Special moment resisting frames (SMRF) are commonly used as lateral-load resisting systems in seismic design. The results of recent studies have shown that the seismic performance of such frames can be improved by paying particular attention to the detailing of their panel zones (PZ) and beams. Panel zones with unequal beam depths appear to be a special case of connection detailing, which has not received sufficient attention so far and could lead to complications in everyday engineering practice. Some full-scale experiments of connections with unequal beam depths were performed, using different continuity plate arrangements (inclined and straight plates), and different corner clip lengths. A companion analytical study was also conducted, for which results have shown that the correct selection of inclined or straight continuity plates, with special detailing of the PZ, could keep the behaviour of the latter within safe margins. Such considerations could prevent the occurrence of failure in the PZ, and significantly improve the seismic resistance of SMRF with unequal beam depths.