Interaction between the shell and elasticbeamcolumn element

[kashif]

Hello STKO Team,

I am trying to model a Light timber frame wall but i am getting convergence issues due to interaction between shell and frame elements.

I am getting the following error
"ERROR: the analysis did not converge
while executing
"error "ERROR: the analysis did not converge""

I have attached the model for you review and would appreciate your response.

Regards

[STKO Team]

It's because the interaction between the shell and the frame is not complete.

If I understood correctly, you defined a Pinching4 material that should represent the shear behavior of nails.
If this is true, you assigned it to the 1st direction of the zero-length. But you have to ensure the interaction has proper local Axes: The first direction should be the tangential one!
By default, the 1st direction of the zero-length is equal to the global X-axis.
So you should define at least 2 interactions: The first for horizontal lines and the second for vertical lines.
Now you have to options:

• Define a single zeroLength material with the pinching in the 1st DOF. Define 2 local axes so that each interaction has the local X axis as the tangential one
• or, leave the default axis, and create 2 different zero length materials. The first one for the horizontal lines with the pinching in DOF 1, and the second for the vertical lines with the pinching in DOF 3.

Finally, you need to enforce continuity of the other 2 traslational DOFs otherwise the wall will be singular. You can do it by using an elastic material in the other 2 DOFs of the zero length