Anisotropic soil–foundation–tunnels dynamic interaction by BEM

Abstract

The subject of the current paper is the dynamic behaviour of anisotropic half-plane with surface relief containing a flexible or rigid foundation and two buried lined or unlined tunnels under time-harmonic waves radiated via embedded line source. The aim is to anticipate the influence of different model key factors such as (a) the soil topography; (b) the soil anisotropy; and (c) the soil–tunnels and soil–foundation–tunnels interaction. The computational tool is the direct boundary element method (BEM) based on the frequency-dependent fundamental solution for 2D general anisotropic solid derived by the Radon transform. The lined tunnels are implemented in the numerical model by the sub-structuring approach, which allows an efficient numerical processing of integrals along the interface boundaries. Numerical scheme verification and parametric studies are performed, and respective concluding remarks are summarized. The obtained results clearly illustrate the dynamic response sensitivity to the soil anisotropy, the soil topography and the complex soil–foundation–tunnels interaction.