Good morning !

I am trying to model a wood connection and get maximal forces that this connection can have. For that I am using a UMAT (that I already checked and stress-strain graphs are correct), many contact properties (Which also seems to work) and connectors in steel.

For convergence purposes (and also because force-control doesn't work very well) I am using Displacement-Control method. However, everytime that I am applying a vertical displacement and plot the total reaction forces I get at my boundary conditions (Pinned BC + I am sure of the total reaction forces, I am not forgetting any nodes, I checked it already) a too low force than in real tests (3-5 times lower).

I am also using mean values of strength parameters so that my model is more realistic. I also tried to change all material parameters (By increasing them of a factor 10) and it isn't useful. I also changed my contact properties and it did not change anything. I can not use force method because it is taking too long to compute and sometimes it is diverging when it should not.

Have you already experienced this problem ?

Best

AP