Seismic Vulnerability Assessment of Reinforced Concrete Structures Equipped with Eccentrically Braced Frames having vertical link

Nowadays, there are various types of existing buildings with poor seismic detailing so they cannot cover the seismic code provisions. Accordingly, the seismic rehabilitation technics should be implemented for these structures. Eccentrically Braced Frame having vertical link is a new strategy for retrofitting of existing RC buildings. In this article, three types of reinforced concrete structures with the same architectural plan having 3, 5, and 8 stories are retrofitted with Eccentrically Braced Frames having vertical links and the seismic fragility curves are developed based on Incremental Dynamic Analysis (IDA) in OpenSEES. The demand statistics in terms of maximum inter-story drift ratio are obtained for 20 sets of ground motion records, the capacity is determined according to the HAZUS-MH limit states, and finally the corresponding seismic fragility curves are developed. The results represent the effect of the implemented retrofit strategy on the seismic vulnerability of this subclass of structures. The median seismic fragility for 3, 5, and 8 story models are increased 35%, 90% and 146 % accordingly, at the complete damage state.