Elastic wave propagation in a 3-D unbounded random heterogeneous medium coupled with a bounded medium. Application to seismic soil-structure interaction (SSSI)

We present a sub-structuring method for the coupling between a large elastic structure, and a strati ed soil half-space exhibiting random heterogeneities over a bounded domain and impinged by incident waves. Both media are also weakly dissipative. The concept of interfaces classically used in sub-structuring methods is extended to ‘volume interfaces’ in the proposed approach. The random dimension of the stochastic elds modelling the heterogeneities in the soil is reduced by introducing a Karhunen–Lo eve expansion of these stochastic elds. The coupled overall problem is solved by Monte-Carlo simulation techniques. A realistic example of a large industrial structure interacting with an uncertain strati ed soil medium under earthquake is nally presented. This case study and others validate the presented methodology and its ability to handle complex mechanical systems