Seismic Response of Buckling-Restrained Braced Frames with Beam Splices

Abstract eng:
Buckling-restrained braced frames (BRBFs) are used in steel buildings to resist lateral earthquake loads. The system ductility of typical BRBFs is limited by the performance of the beam-column-gusset connection regions at large drifts. Experiments have indicated that connection ductility may be improved by splicing the beam outside the gusset region. Dynamic analyses were performed to investigate the impact of these beam splices on the seismic response of BRBFs. Two series of analyses were performed. In the first series, BRBF frames were analyzed as two dimensional systems subjected to in-plane loading. Beam splices were modeled using rotational springs. The impact of the strength and stiffness of the splice was investigated. Frames were subjected to a suite of ten ground motions scaled to represent design events. The second series of dynamic analyses involved more advanced models. Three dimensional models were developed where connection regions including the gusset plates were modeled with shell elements. These models were subjected to ground accelerations oriented at different angles to the frame. Models were considered with and without beam splices outside the gusset region. The use of beam splices proved effective in reducing stress build-up in the gusset-to-beam and gusset-to-column connecting regions. Maximum gusset stresses in the first story beams and columns had a 50 percent reduction in magnitude. Adding beam splices had negligible impact on drifts.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket