Seismic performance assessment and benefit-cost analysis of mid-rise reinforced concrete base-isolated building using double-curvature friction pendulum bearings

Abstract

Base isolation technology is highly advocated by the research community worldwide for efficient mitigation of earthquake-induced vibrations and alleviating seismic risks posed to civil engineering structures. However, the construction cost of implementing this advanced technique to real-life buildings compared to the conventional ones remains a debatable topic, and a research problem to examine. Therefore, the present study focuses on assessing the short- and long-term cost-benefits of base-isolated buildings vis-é-vis fixed-base buildings over their service life. Notably, the benefit-cost analysis methodology prescribed in FEMA-356 is utilized to quantify the economic consequences of natural calamities on the base-isolated building. Various aspects, such as structural responses, damage vulnerability, collapse probability, and occupancy rate are thoroughly analyzed. A real-life mid-rise reinforced concrete building in the Indian subcontinent, having double-curvature friction pendulum bearings (FPBs) at stilt level is deliberated in this study. A series of quasi-static and nonlinear time-history analyses are carried out based on the recently drafted Indian seismic code for base isolation to comprehend the improved performance of the FPB-isolated building. Additionally, two fixed-base buildings are designed with an aim to make their performance almost at par with the base-isolated building, and then to assess the cost implications of attaining such comparable performance. The outcomes of this study, particularly the structural performance enhancement and cost benefits, will assist both decision makers and structural designers to have a persuasive opinion on the better adaptability of the base isolation technology for improved seismic resistance and financial outlooks associated thereof.