Numerical Experiments on Dynamic Response Evaluation of Soil Structure Interaction Effects

Soil–Structure Interaction is an important issue in the dynamics of structures, being not taken into consideration, in many cases, due to complex volume of computations. The interaction between soil and foundation becomes meaningful especially in the case of rigid structures and foundations, being object of intensive investigations in latest 30 years. The present study is aiming to evaluate the dynamic response of a foundation structure, interacting with the soil using the computational environment offered by EDT software (version 2.2, 2010). Soil–structure interaction of rigid foundations is characterized by impedance functions. They are determined in this paper for a soil which may be arbitrarily layered and is underlained by a rigid or an elastic half space. Vertical and rocking motions are considered. Two methods for the computation of the impedance functions are applied. The first approach is the so-called Thin Layer Method (TLM) following a theory developed by Waas-Riggs-Werkle (1985). It has been implemented by Horst Werkle (1985) in a MathCAD environment. In addition a solution in the wave number domain using the Elasto-Dynamic Toolbox developed by Schevenels (Katholieke Universiteit Leuven, Belgium – 2008) is implemented in MATLAB. The results of dynamic analysis obtained with both theories are compared with the analytical solution for an elastic half space obtained by Gazetas (1983).