Investigating Effect of Friction-yielding Top Plate of Rigid Connections on Seismic Response of Special Moment Frames

Acceptable seismic performance, ease and low cost in design and implementation are advantages of passive dampers, but fixed performance parameters corresponding to the type and amount of input energy reduce their efficiency. In this research, a new two-level passive damper in rigid connections with variable stiffness, strength, and energy absorption capacity is introduced and its seismic performance in ۵, ۱۰, and ۱۵-story steel frames is evaluated with nonlinear dynamic analysis using SAP۲۰۰۰ software. The results show that, despite the different dynamic parameters in the selected seismic records, such as the frequency content and duration of ground motions, the performance of the structures under all earthquakes has improved significantly, which confirms the effectiveness of the proposed damper in rigid connections on improving the seismic performance structures. Besides, results prove the proposed damper effectiveness on decreasing the structural response such as maximum displacement and base shear. The average displacements reduced by ۶۱%, ۵۱% and ۱۶% compared to those of BSEEP-۴ES connections for the ۵, ۱۰ and ۱۵-story frames, respectively. Besides, maximum base shear forces reduced by average of ۲۹% and ۱۵% compared to those of BSEEP-۴ES connections for the ۵ and ۱۰-story frames, respectively.

کلیدواژه ها:

Two-level control system ، friction-yielding damper ، Top plate ، Ductility ، Nonlinear analysis