Hi there
Please could you pass the following suggestion to the relevant personnel?
The option to define stiffness in orthotropic soil materials in Plaxis 3D may be useful. For example when approximating using the Mohr-Coulomb soil model (which exhibits an overestimation of stiffness and therefore swelling-like effects in unloading/excavation stages) for a soil volume, defining different values of E' (considering Drained material in this case) may assist with this.
The inputs of E' may be as simple as defining a value in each of the orthogonal directions x, y, and z.
This may help forego using more "thorough" soil models that require additional testing, preliminary data etc.
Just a suggestion, if you'd also like to share your thoughts
Thanks!