COMPARISON OF SEISMIC PERFORMANCE OF SPECIAL CONCENTRIC BRACED FRAMES WITH BUCKLING-RESTRAINED BRACED FRAMES IN VIEW OF SEISMIC-INDUCED LOSSES

Comparison of seismic performance for various lateral-resisting systems is of great importance towards appropriate structural system selection. The comparison can be done based on various parameters (i.e. seismic structural responses, energy dissipation capacities, structural yield strengths …). One of the most common lateral-resisting system is the concentric braces. Special Concentric Braced Frames (SCBFs) and Buckling-Restrained Braced Frames (BRBFs) are the two types of concentric braced systems. The main goal of this research is to present and to compare the structural seismic-induced losses for the mentioned types of concentric braced frames. To achieve this goal, three sampled frames with 4, 8 and 12 stories, with BRBF and SCBF lateral-resisting systems, are considered as sampled structures. To compute the structural seismic-induced losses of the sampled frames, the conditional method is applied. Probabilistic seismic hazard, probabilistic structural demand, probabilistic seismic-induced damages and probabilistic loss models are combined for each frame. Seismic hazard curves are predicted based on the interpolation of power functions to the empirical intensities corresponding to two mean annual frequency of exceedances (MAFEs). To achieve the probabilistic demand models for the sampled frames, incremental dynamic analysis (IDA) of the relevant finite element models is conducted using OpenSees tool. Besides, the probabilistic seismic-induced damages are calculated based on IDA results considering the drift thresholds proposed by HAZUS report. The loss curves are adopted from HAZUS report too. Finally, combining the aforementioned probabilistic curves, the final loss curves of the sampled frames are computed. The achieved results show the superiority of BRBF system, in view of seismic-induced losses, comparing with SCBF system. As the limitation of this research, it should be mentioned that the loss calculation is conducted neglecting the initial cost of construction.

Keywords:

Seismic Performance , Special Concentric braced frame , Buckling-restrained braced frames , Seismic-induced losses