Soil-structure interaction in the time domain

Abstract Saturated soils, which are two-phase media, display time-dependent behaviour at constant loading. The resulting phenomena of consolidation and creep causes deformations which are significant compared to instantaneous deformations or those which occur during the construction period of the structure. Redistribution of shear forces, bending and torsional moments in the structure occur due to differential settlements rather than the total settlements. Most of the interaction analyses presented so far are based upon the elastic behaviour of the whole system. An attempt has been made in this paper to present a three-dimensional visco-elastic finite element formulation for studying the interactive behaviour of space frames, taking into account the stress/strain-time response of supporting soil medium. The paper also underlines the methodology for evaluating time-dependent visco-elastic constants for the soil mass and presents a comparison of the resulting structural behaviour with that when interaction is neglected.