1. Reference problem

1.1. Geometry

Software MISS3D uses the frequency coupling method to take into account soil-structure interaction. This method, based on dynamic substructuring, consists in dividing the field of study into three sub-areas, which are soil, foundation and structure. Here we treat the case of a superficial foundation alone (without structure). It is a circular foundation with radius \(>\). The geometry is that of the foundation treated in reference [bib1] and represented in paragraph 3.

1.2. Material properties

The soil corresponds to a homogeneous semi-infinite medium whose characteristics are summarized in the table below:

Layer	Thickness \(>\)	\(>\)	\(>\)	\(>\)	\(>\)
Layer 1		1875	0.33	0.33	1800	0.10
Layer 2	Substratum	1875	1875	0.33	1800	0.10

Table 1.2-1: Mechanical characteristics of homogeneous soil

The foundation is considered rigid and weightless.

1.3. Boundary conditions and loads

Seismic loading consists of a unit excitation in the frequency domain. This makes it possible to directly determine the transfer functions (between seismic excitation and structural response). The foundation is considered rigid. This results in a solid bond of the GROUP_NO radier.