Learning Forum

[DIANAG]

Hi everyone, I'm having a strange trouble ....I need to use the compression only support command, but I don't find it! I used it many times, but now is not in my window anymore. Here I reported an image of the insert menu of static structural.

[Ashish Kumar]

Do you have a surface of the surface body selected when you try to insert this boundary condition?

Regards Ashish Khemka

[DIANAG]

I have a surface....I saw in the manual after your question that ansys doesn't apply compression only support on surfaces but only in bodies. I can't understand why!
I have a very huge model composed of surfaces, and I have to transform the surface on which I want to apply the compression-only support to a body element. Is that right?
Thank you

[peteroznewman]

Compression-only support automates a process that you can do manually for surface bodies. The automatic process copies the face, makes it a rigid body, fixes it to ground and applies a frictionless contact between the scoped face and the copy made.
I think the reason ANSYS only does this for solids and not surfaces is because on a solid, the side of the face where the solid material exists is known, so the direction that opens a gap is known. For a surface, ANSYS can't know which direction to move that would open the gap, only you know that.
If you follow the same steps, when you define the contact between the two surfaces, you have to carefully select the Top or Bottom of each surface so that your intended direction of gap opening is created and not one of the three combinations that is wrong.