Hi
I have been testing how to implement point moments and nodal supports in shell models. What I mean by this, is to have a single point from where you can check reactions or apply point moments like in full beam models.
Best I have managed to do is combining beam and shell models in a way shown in the pictures below. So those short lines at the end of the circular pipe shell model are modelled as beams. Shells are DKT and beams are POU_D_E if that is any significance.
Green arrow in the first image is FORCE_NODALE. The bottom point in the deformed view is supported with DDL_IMPO in all translations and rotations, so fixed. Reaction moment I get is 100 % correct with the analytical solution for cantilever beam with a point load in the end.
In the second image the red point is a nodal group where the fixed point is applied. I used LIAISON_SOLIDE to connect the DOFs of the purple points together. Purple point in the middle of the tube belongs to the mesh of the beam element.
So my question: is this approach the best/only way to to achieve this? LIAISON_SOLID seems to be pretty simple to use and the deflections and stresses are pretty accurate compared to analytical solution. There is some stress concentration when changing from beam element to shell but nothing too large.
