Comparison of Fixed Base and Base Isolated Hotel Building Located in Kufri

Abstract

Base isolation technology works by separating or greatly reducing the lateral movement of a building’s superstructure from the movement of the ground/foundation during a seismic event. The ultimate purpose of a base isolation system is to reduce the seismic forces exerted onto a reducing the superstructure’s spectral accelerations. These accelerations are reduced both by increasing the effective fundamental period of the isolated structure and through damping caused by energy dissipated within the isolation bearing. Here, 4 story commercial building was analyzed which is located in Kufri it is a small hill station in Shimla district of Himachal Pradesh state in India. It is located 13 km from the state capital Shimla on the National Highway No.22 Seismic Zone IV. Kufri is located at 31.10°N 77.25°E. It has an average elevation of 2,290 meters (7,510 feet). Strata is hard rocky with bearing capacity around 220kn/m2. The main focus of this study is to compare response of fixed-base and baseisolated model on the basis of Member Forces, Story Drifts, Time Period. From the work done, it was analyzed that there was large reduction in member forces. Member forces were reduced to about 40% by implementing base isolation technique. Time period of the structure was increased as compared to fixed base with results in decreasing acceleration and further there was decrease in story drifts of the structure