To consider soil-structure interaction using the constrained modulus method, the “Stiffness modulus” material parameter can be defined for soil-type materials.
This requires soil material from the library to be used as the basis for entering the soil properties.
The “Material Properties” tab is available for library materials. The “Oedometer modulus” parameter is available in this tab, as shown in the following image. This corresponds to the “stiffness modulus.”
Eoed=Es
The stiffness modulus can be converted to the modulus of elasticity using the Poisson's ratio. RFEM performs the conversion for you. As soon as one of the properties is modified, the conversion for the other value follows.
For more information on the background of the properties, refer to the chapter “Compressibility” of the Geotechnical Analysis online manual.