I experienced unrealistic bending moments in my cirular tunnel lining using Plaxis 3D. There is no change of direction (richt picture).
I tried modelling the same tunnel in 2D and i work perfectly fine (left picture).
Dear Jonas,
My first guess in any situation where two calculation results do not match is that the material definition might be different, especially checking the units used.
Other than it is difficult to make any guess.
I leave it to the fellow geotechnical engineers out there to share their guesses, but for us, we could give the models a look.
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