Performance-based design of soil – foundation – structure systems

Soil foundation structure interaction (SFSI) is incorporated herein to the study of seismic performance of typical structural models. As opposed to traditional seismic design, soil foundation system compliance is taken into account in the estimation of structural performance. The influence of several parameters on structural response, such as soil to superstructure stiffness ratio, structure slenderness, and soil to structure mass ratio, are incorporated in a series of parametric elastic time history analyses using the finite element method. The SFSI effects are examined in terms of performance point values, which are designated graphically at the intersection of the effective input motion demand spectrum and the SFSI system fundamental period. It is demonstrated that neglecting SFSI in performance-based design may lead to overestimation of the design forces, in terms of spectral acceleration and displacement.