Seismic performance assessment of novel self-centering friction-based eccentrically braced frames

Abstract

Eccentrically braced frame (EBF) is a robust seismic force resisting system. EBF provides strong stiffness and clear energy dissipation to resist the earthquake shaking. However, after strong earthquake shaking EBF may be difficult or too expensive to repair. This could result in prolong down time and significant repair costs. In this paper, a novel energy dissipation device named self-centering conical friction damper (SCFD) is implemented within EBFs to dissipate the earthquake energy and to reduce the residual drift of EBF. The new system is named self-centering friction-based EBF (SCFB-EBF). The performance of the SCFB-EBF is compared with conventional EBF. Three prototype buildings with 3-, 6-, and 9-stories were designed using conventional EBF according to the AISC341-16/ASCE7-16 specifications and SCFB-EBF by replaced the links of the EBF with SCFD. The prototypes were subjected to a suit of 44 ground motions at both the design based earthquake (DBE) and maximum considered earthquake (MCE) shaking intensities according to the FEMAP695 procedure. Detailed nonlinear time history analyses were carried out using OpenSees. The results of the nonlinear time history show that SCFB-EBF has superior performance compared to the conventional EBF. In addition, the residual drifts of the SCFB-EBF were reduced significantly compared to the conventional EBF. Performance-based earthquake engineering (PBEE) assessment was also conducted to examine the performance of the prototype buildings. The results show that SCFB-EBF has lower repair cost at both DBE and MCE levels. Hence, the study shows that the SCFB-EBF can be used as an efficient alternative compared to seismic force resisting system.