Parameters Influencing Response of a Base Isolated Building

In order to illustrate the effect of damping on the response of a base-isolated building, a large investigation is made. It consists in a parametric study which takes into account the progressive variation of the damping ratio (10% to 30%) under different nature of seismic excitations (near and far field). A time history analysis is used to determine a response of the structure represented in this case by terms of relative displacements and inter-stories drift at various levels of the building, additionally a strong deviation of energy capacity by the LRB (Lead Rubber Bearing) system will be recorded, therefore the results show that the efficiency of the isolator increases with the assumed damping ratio, provided that this latter is less or equal to 20%. Beyond this value, the isolator becomes less convenient.