SEISMIC PERFORMANCE ASSESSMENT OF HYBRID SELF-CENTERING BUCKLING-RESTRAINED BRACED FRAME SYSTEMS
Ahmad Fayeq Ghowsi *, and Dipti Ranjan Sahoo
Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi-110016, India
Buckling-restrained braces (BRBs) are preferred to the conventional steel braces as lateral force-resisting elements in civil structures because of their nearly-symmetric hysteretic response, high displacement ductility, and good energy dissipation potential. However, the main disadvantage of buckling-restrained braced frames (BRBFs) is the excessive residual drift in the post-earthquake scenario. Self-centering buckling-restrained braced frames (SC-BRBFs) have been developed for the better energy dissipation capacity along with the reduced residual drift response. This study is focused on the evaluation of seismic response of BRBFs, SC-BRBFs, and hybrid frames. through non-linear time-history analyses. The study frames, (i.e., 3-story, 9-story, and 20-story) are designed as per the US seismic code AISC 341-2014 provisions by considering the SC-BRBs as the combination of BRBs and shape-memory alloy (SMA) rods. The main parameters investigated in the numerical analyses are drift response, energy dissipation potential, and hinge mechanisms. The analysis results showed the better seismic performance for the hybrid systems as compared to BRBFs and SC-BRBFs.
Buckling-restrained braces; Drift response; Numerical modelling; Seismic analysis; Self-centering braces