Non linear convergence

[faisal.aaouatif]

Please find attached a simple model of a raft under three column with non linear analysis.

i can not understand how under the exploitation loads ( before talking about seismic ones ) it can not converge ?

Help needed.

Thank you

[Artur.Kosakowski]

You need to slightly increase the tolerance for case 2 and combination 7.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[faisal.aaouatif]

Thank you Artur .

It had resolved the problem ; but not for the remaining combination ( not included in the previous model ).

What is bizzare is that it gives a instability type 2 for a node 175 (why ?)  for 04 combinations . and then no convergence.

you will find attached the complet model.

Thank you for you time.

[faisal.aaouatif · Accepted solution]

Artur ,

I found that problem is coming from unsuficient dimension of the raft ; an increase in both two direction solved the instability issue.

Thank you very much