*M. Tech. Final Semester Student, Structure Engineering Department of Civil Engineering, Indoglobal college of Engineering & technology, Abhipur(Mohali), Punjab, India
**Astt. Professor, Department of Civil Engineering, Indoglobal college of Engineering & technology, Abhipur (Mohali), Punjab, India
Earthquakes are a major threat to human lives and to the integrity of the infrastructures in seismic regions. Structures are the worst hit with the phenomenal damages due to ground motions resulting from earthquakes. Recent researches and studies have led to new techniques to reduce the damages caused by earthquakes on structures and these techniques are applied for innovative structural design. One of the techniques is the base isolation method, which is used to design structures against earthquake damages by using seismic isolators to change the dynamic characteristics of a structure. In this study, three bay 4 and 8-storey reinforced concrete structures are analysed as isolated and fixed-base. Laminated rubber bearing (LRB) is used as an isolation system. Nonlinear behaviour of both isolation system and super-structure are considered in the modelling. The behaviour of designed models under dynamic loads is analysed using ETABS (Extended Three Dimensional Analysis of Building System) computer software. Bhuj Earthquake Data (Gujarat Earthquake) are chosen as the ground motions (i.e. Linear Time History Analysis). At the end of analysis (i.e. Linear Response Spectrum and Linear Time History Analysis), the response quantities are mode period, displacement, storey accelerations and base shear forces are compared and results are drawn for isolated and fixed-base structures.
