Diagrams of Effective Periods and Dampings of Soil-Structure Systems

Abstract

Diagrams of effective periods and dampings of soil-structure systems for embedded foundations in soil layers are presented. The interacting system considered is similar to that used in building codes to account for the inertial interaction. The soil is replaced with accurate impedance functions that are taken from available tables, which include numerical results for different foundation depths, sidewall heights, and layer depths. Effective periods and dampings for a number of system parameters are directly obtained from examination of the transfer function of the coupled system. A set of design aids for most common interaction conditions encountered in practice are developed; its application is illustrated with a practical example. Additionally, information to take the kinematic interaction into account is provided.