Seismic performance of prefabricated steel beam-to-column connections

摘要

Three types of prefabricated steel beam-to-column connection different from common welded unreinforced flange-bolted web (WUF-B) connections are examined in this paper. Full-scale specimens with specific joint configurations were prepared, so that the effects of joint detail on the failure mode, ultimate capacity and ductility could be identified. They were tested under cyclic loading to further investigate their seismic performance. Experimental results showed that the measured moment capacities of these connections at the face of a column flange reached 120% to 140% of the beam's full plastic moment. The maximum plastic rotations of all connection types were greater than 0.025 rad and the cumulative plastic rotations were 20 to 30 times the maximum plastic rotation. In this way, connection Types Ⅰ and Ⅲ were capable of accommodating a story drift angle of 0.04 rad. These results demonstrated excellent joint strength, and showed potential opportunities for connection Types Ⅰ and Ⅲ to be used in special moment frames (SMFs) in AISC Seismic Provisions, and for connection Type Ⅱ to be used in intermediate moment frames (IMFs). Finite-element analysis was performed and showed good agreement with the experimental results. It was found that rigid end-plate assumption is not appropriate for connection Type Ⅰ, and higher likelihood of fracture was detected in the cover plates than in beam flanges for connection Types Ⅱ and Ⅲ.