Novel joint for improving the collapse resistance of steel frame structures in column-loss scenarios

In this study, to improve the collapse resistance of steel frame structures, corrugated steel plates are welded between the inner side of the flange of the I-shaped beams and the column to form novel steel frame joints with corrugated plates (reinforced joints). Collapse resistance tests of the novel reinforced joints under welded and bolt-welded connections are conducted. After a finite element model is validated, the effects of the circular arc length, thickness, and central angle of the corrugated plates on the collapse resistance of the novel reinforced joints are analyzed, and design recommendations are proposed. Results show that the failure modes of the tested specimens are the fracture failure of the beam flange outside the reinforced area and the sequential fracture of the tension flange of the joint region and corrugated plate. Compared with the original specimens, the bearing capacities and ductility of the reinforced specimens are significantly improved. A partial or complete out-shift plastic zone can be realized in the novel reinforced joints. The novel reinforced joints can effectively improve the collapse resistance of steel frame structures under welded and bolt-welded connections without affecting their seismic behavior. The corrugated plate even provides an additional resistance reserve for steel frame structures.

Automated summary

This study focuses on improving the collapse resistance of steel frame structures by welding corrugated steel plates between the flange of I-shaped beams and the column to create reinforced joints. The collapse resistance tests were conducted on the novel reinforced joints with welded and bolt-welded connections. The study analyzes the effects of the circular arc length, thickness, and central angle of the corrugated plates on the collapse resistance and proposes design recommendations. The results show that the reinforced joints significantly improve the bearing capacities and ductility of the steel frame structures without compromising their seismic behavior.