BENDING AND SHEAR BEHAVIOUR OF RC BUILDING WITH AND WITHOUT BASE ISOLATION USING NON LINEAR ANALYSIS METHOD

Rakshith K J, Spandana B, Ganesh M

Abstract: A huge proportion of world’s population lives in regions of seismic hazards, at risk from earthquakes of varying severity and frequency of occurrence. Earthquake causes significant loss of life and damage of property every year. So, to mitigate the effect of earthquake on building the base isolation technique is one of the best solutions. Seismic isolation consists of essentially the installation of mechanisms which decouple the structure from base by providing seismic isolators. The seismic isolation system is mounted beneath the superstructure and is referred as ‘Base Isolation’. Base isolation is one of the most widely accepted seismic protection systems used in building structures in earthquake prone areas. The base isolation system separates the structure from its foundation and primarily moves it relative to the upper structure. The purpose of this study is to decrease the base shear and column and beam forces and due to earthquake ground excitation, applied to superstructure of the building by installing base isolated devices at the foundation level and then to compare the different concerts between the fixed base condition and base isolated condition by using ETABS 2016v software. In this study, G+14 story RCC building is used as test model. Lead rubber bearing and high damping rubber bearing is used as base isolation structure in this study. Nonlinear time history analysis is used on both fixed and base isolated buildings. Comparative study is contains two portions. They are comparisons between fixed and base isolated buildings and comparative study of performance by two different time history data like El-Centro and Bhuj. Finally displacement and column and beam forces and moments are compared from two time histories analysis between fixed and base isolated condition. It is found that displacement is increased with base isolated building. And beam forces are decreased in base isolated than fixed base building.

Keywords: Base Isolation, RC Building, Lead Rubber Bearing, High Damping Rubber Bearing, Nonlinear Time History Analysis

DOI: https://doi.org/10.15623/ijret.2017.0608022