Published Paper Details:

An earthquake is a natural disaster which causes damages to the structures and responsible for loss of life. Earthquake refers to shaking of ground and is unpredictable. It is not possible to prevent the earthquake and thus attempts have been made to resist the earthquake forces acting on the structures. Base isolation is one of the effective method of resisting earthquake forces. They consist of rubber bearings which are sandwiched between superstructure and its foundation. These rubber bearings absorb earthquake energy thus resulting in energy dissipation. In this thesis work, an attempt is made to study the behavior of structures with and without base isolation system. Lead Rubber Bearings (LRBs) are used as an isolation system. Four models of plan 20m x 20m with different heights are modelled and analysed in ETABS 2016 software. Response spectrum method is carried out for the analysis of models. The models are analysed for two different zones of India. I.e. Zone II (low seismic risk) and Zone V (severe seismic risk) as per IS 1893:2002 (Part 1). From the analysis of fixed base models, maximum axial reaction is obtained and LRBs are designed manually as per Design of Seismic Isolated Structures by James M Kelly and Farzad Naeim. The parameters such as storey displacements, storey drifts and mode periods are compared between fixed base and isolated base models. It is found that, storey drifts are reduced in the building with isolated base. Storey displacements and mode periods are increased due to increase in the flexibility of isolated base building. Hence it is found that the use of base isolation system reduces the earthquake forces transferring to the superstructure.