Is it possible to perform an analysis according to the stiffness modulus method in RSTAB or RFEM?
No, in RSTAB and RFEM, it is not possible to perform an analysis according to the stiffness modulus method. Instead, a version of the subgrade reaction model is used. The stiffness modulus E cannot be taken into account.
RFEM uses a multi-parameter subgrade model. It can carry out very realistic settlement calculation. The problem, however, is to find precise values for the parameters C1,z, C2,x, and C2,y.
The add-on module RF-SOILIN helps you do this. From the loads and the data of the geotechnical report (stiffness modulus or modulus of elasticity and poisson's ratio, specific weights, layer thicknesses) the subgrade parameters are calculated for each individual finite element by using a nonlinear method. These parameters are load-dependent and influence the behavior of the structure. This is addressed by an iterative procedure. The results are realistic settlements and more precise internal forces in the structure.