Seismic resilience evaluation of base-isolated RC buildings using a loss-recovery approach

Seismic isolation systems, especially friction pendulum bearings (FPBs), are used as ideal seismic protection strategies in performance-based design. Furthermore, FPBs can increase the functionality of buildings by minimizing interruption of use of the facility (e.g., operational performance level) and reducing seismic demands on the structural and non-structural elements. The primary objective of this paper is to investigate the seismic resilience of reinforced concrete (RC) buildings, especially essential buildings in compliance with a loss-recovery approach. To this end, an analytical examination is conducted concerning a six-story RC building, which was mainly designed under the Uniform Building Code (UBC in International Conference of Building Officials, Whittier, CA, 1997) for a high-risk seismic zone. The incremental dynamic analyses of the fixed-base and base-isolated structures subjected to a set of near and far-fault ground motions are carried out for getting seismic fragility and functionality curves as well as the resilience of structures using a loss-recovery approach. The proposed methodology is employed to special buildings such as hospital buildings, with and without using the FPBs considering different seismic hazard scenarios that could occur within the investigated region. At the end of the paper, a parametric study is conducted by changing the building and pendulum parameters. The benefit of the suggested approach is found in terms of loss-recovery and seismic resilience that will be well recognized by the decision-maker for better planning to decrease seismic losses, rather than waiting for an earthquake and paying for it afterward.