User element and constitutive tensor

[Jorgen]

It should work also with a force boundary condition.
I must say, however, that the error message you listed is quite odd.

I am not sure how to interpret it

[DaVinci]

Hi the error message is from a cook membrane test with the UEL.

There were 8 elements in total, 4 of which had a shear force applied to one surface, and they each gave the error stated before.

If I changed the shear force to a shear displacement, it worked.

But this is not the way the standard cook membrane test should be performed.

[DaVinci]

To answer my own question:

Forces can be applied directly to nodes in UELs, however pressures cannot be used as surfaces are not allowed/defined for UELs fro some reason. (as I understand it)

Anybody know how to get around this?

[Jorgen]

I afraid that I don't have a good answer to that.
Anyone else with suggestions?

-Jorgen