Seismic Performance Factors of Elliptic-Braced Frames with Rotational Friction Dampers through IDA

Abstract

In recent decades, various strategies have been employed to enhance the seismic resilience of structural systems in the event of earthquakes. One such innovative method is the elliptic-braced moment-resisting frame with a rotational friction damper (ELBRF-RFD), which serves as a displacement-restraint bracing technique connecting the elliptic brace to the upper beam. To design an ELBRF-RFD based on contemporary guidelines, for the first time, this study introduces the quantification of seismic performance factors (SPFs) through incremental dynamic analysis (IDA). The research then proceeded to design 3-story, 5-story, and 7-story archetypes in type II soil using the presumed SPFs. A comparative analysis was conducted with inverted-V braced frames equipped with rotational friction dampers (CBF-RFDs). The performance of each archetype was evaluated through nonlinear static pushover analysis (NSPA) and IDA, employing 15 earthquake records from the past and using the OpenSees software. For the response modification factor, suggested values of 11.2 (allowable stress method) and 7.8 (ultimate limit state methods) were identified. Furthermore, the collapse probability of archetypes was determined by employing fragility curves and considering sources of uncertainty.