Seismic Assessment of Steel-frame Buildings Mounted with Base-Isolated System

A multi-Storey steel frame building against earthquakes has always been a challenge for structural engineering and researchers. Many seismic protection systems have been investigated overtime where the Base Isolation system has widely been used and implemented. It works on the principle of dissociation of substructure to the superstructure. In the present paper, different multi-storey steel frame buildings are evaluated, which are mounted with Lead Rubber Bearing (LRB) as a base isolator. LRB has been designed in compliance with the FEMA and ASCE guidelines. Further, a relative study is presented for evaluating the traditional fixed-base structure with a base-isolated building by performing a time history analysis. Base shear, inter-storey drift, acceleration, and displacements are examined as a result of the study. The outcome shows significant contributions towards reducing acceleration, inter-storey drift and base shear distributed over the floors. Moreover, LRB not only absorbs the seismic energy but also substantially decreases the destructive effect during an earthquake.