Performance of a multi-story structure with a resilient-friction base isolation system

Complex frequency response functions and excitation–response relations for stationary random process are formulated to estimate responses of multi-story superstructures isolated with resilient-friction base isolation (R-FBI) system. The equivalent linearization technique is also used to linearize the nonlinear governing equations of motion of R-FBI system occurred between the parallel actions of the resiliency of rubber and friction of Teflon-coated plates. In this approach, the spectral density functions for both the relative displacement response and absolute acceleration response of N degrees of freedom systems are derived. The applicability and accuracy of the proposed methodology are examined by comparing the resulting responses obtained from this study with those calculated from time history analysis based method. These two studies demonstrate good agreement in terms of characteristics of peak responses. Extensive sensitivity analysis to find the influence of various important structural parameters on the behavior of structures isolated with R-FBI system is also carried out.