Seismic performance evaluation of steel frame systems with self-centering beam-column joints and self-centering column bases

This paper applied a new type of self-centering prestressed beam-column joint with weakened flange cover plates (SPPSJ) and column base (SPSCB) to steel frames, forming a prefabricated self-centering steel frame system (SCBCSF). The seismic performance and collapse resistance performance of the SCBCSF were evaluated. A six-story steel frame was designed, including four structural types and eight layout schemes. OpenSees was utilized to establish numerical models. Seismic time-history analysis and incremental dynamic analysis (IDA) were conducted. The results show that SCBCSF exhibits excellent post-earthquake self-centering capability. The seismic performance of the SCBCSF meets the requirements of Building Seismic Design Codes. The self-centering effect of SPPSJs when located only at the first floor is not ideal; SPPSJs placed inside the plane or in floors where time-history analysis predicts peak story drift exceeding 1 % effectively reduces post-earthquake residual displacement. The arrangements of SPSCBs along the inner and outer sides of the plane have little impact on the self-centering effect. The collapse margin ratio (CMR) of the SCBCSF is slightly lower than the rigd steel frame (RSF) but still meets the collapse performance requirements. These findings provide valuable insights for the design and application of the SCBCSF.