Evaluation of Dynamic Responses of the Base-Isolated Buildings under Earthquake Excitations

In the present study, nonlinear dynamic responses of the reinforced concrete building structures with lead rubber isolation bearing (LRB) that subjected to earthquake excitations are investigated. Bilinearforce-deformation behavior for LRB isolator is considered. Mechanical properties of isolators arecalculated. Then, designed and utilized in analysis. Evaluation is performed by means of the nonlinear time history analysis method for 4-, 8-, 12-story reinforced concrete buildings in cases of the fixed-base and isolated-base. To perform analysis, Imperial Valley, Northridge and Duzce records of earthquakeapplied to building models. The results of analysis showed that made displacement at the base of isolated buildings fits to design displacement predicted in initiating calculations and not exceed allowable zone. LRB isolation system has high effect on reducing structural responses. Also increasingnumber of floor in base-isolated buildings causes that dynamic responses decrease less than small building structure