I am posting this question upon request after e-mail contact. It has since been resolved for me.
I’m working on a concrete slab on pile-foundation, and I keep getting this error message.
The “Notification” list doesn’t give me any information to understand the problem. It only says “Suspected ill-conditioning or pivot is negative”.
This was eventually resolved for me. The plate thickness was too low, causing the upper and bottom layers of the calculation model to ‘collapse’, if I understand correctly.
I uploaded the file for educational purposes.
Tankpit A.xfem (390.8 KB)