In this paper the effects of mass eccentricity of superstructure as well as stiffness eccentricity of isolators on the amplification of seismic responses of base-isolated structures are investigated. Superstructures with 3. 6 and 9 stories and aspect ratios equal to 1. 2 and 3 are mounted on a Triple Concave Friction Pendulum (TCFP) bearing. https://www.hindigyanvishv.com/