Dynamic Interaction of Two Adjacent Foundations Embedded in a Viscoelastic Soil

This paper studies the dynamic interaction for two adjacent rigid foundations embedded in a viscoelastic soil layer. The vibrations originate from one of the rigid foundations placed in the soil layer, which are subjected to harmonic loads of translation, rocking, and torsion. The dynamic responses of the rigid surface foundations are solved from the wave equations by taking into account their interaction. The solution is formulated using the frequency domain boundary element method (BEM), in conjunction with Kausel–Peek Green’s function for a layered stratum and the thin layer method (TLM) to account for the interaction between the two foundations. This approach allows us to establish a mathematical model for determining the compliance functions of the two adjacent foundations with regard to their spacing, substratum depth, masses, shapes, embedding, load intensity, and frequencies of excitation. The soil heterogeneity was taken into account for the cases of one or two layers of soils over a rigid bedrock and semi-infinite soil. The analysis of the present study indicates that the effect of several parameters on the dynamic interaction response of two adjacent foundations is nonnegligible. In particular, the dominant influence of some parameters, such as the heterogeneity of the soil, shape of the foundations, and the load intensity, compared to the other ones is clearly revealed.