Comparative study on the effectiveness of fluid viscous dampers and base isolation: an approach toward enhancing seismic performance of composite structures

This research paper presents an in-depth investigation into the seismic response of hybrid structures integrated with fluid viscous dampers (FVDs) and base isolation. Severe seismic events pose hazardous threats to hybrid structures, making it imperative to develop effective strategies for enhancing their seismic resilience. The study aims to assess the seismic performance of hybrid structures featuring Circular Hollow Section (CFST) and concrete-encased steel (CES) columns in comparison with conventional columns in RCC structures, leveraging the attributes of both FVDs and base isolation. Finite element analysis is employed to model the hybrid structure, and performance evaluation is conducted based on key parameters, including inter-story drifts, fundamental time period, stiffness, story displacements, base shear and overturning moments, utilizing the response spectrum approach. The study focuses on 16-story hybrid structures, having three different shapes of CFST and CES columns, incorporated individually with FVD, Lead Rubber Bearings (LRB) isolators, and a combination of both. To foster a more comprehensive understanding, the dampers are placed at two different heights, i.e., H and H/2 height of the building. The results demonstrate a noteworthy reduction in the structural response of the hybrid structure when subjected to seismic events through the integration of FVDs and base isolation. Comparative analysis of each energy-dissipating system reveals that a synergistic combination of FVDs and base isolation yields superior performance compared to their individual use. By bridging the existing research gap and investigating the intricate behavior of hybrid structures equipped with FVDs and base isolation, this research contributes significantly to the fields of earthquake engineering and structural resilience. The study contributes valuable insights into the advantages and limitations of each system, aiming to facilitate the development of safer and more resilient buildings, particularly in regions prone to high seismic activity.