Instability Errors

[Roub3a]

Hello,

In this model, the horizontal stability is ensured by the x bracings on axes 34, 36, A and C and by the fixed frame on axes B and 35.

All the "interior" beams supporting the live loads are released to work as simply supported beams.

However, when I run the model, instabilities are detected and I cannot find the problem while I think that my structure is stable.

Can you please help me out find the source of the error?

Thanks a lot!

Cheers

[Rafal.Gaweda · Accepted solution]

Block additionally RZ in all supports or modify beam releases in the way to prevent columns to rotate around global Z axis (local X).

[Roub3a]

Hello again,

Thank you for your reply.

I tried blocking RZ in all of my supports but I still have an instability of type 3. Could it be related to the big difference in my sections thus causing large stiffeness differences in the model? Does this give erronated results?

[Rafal.Gaweda · Accepted solution]

Spoiler

Yes, igonore this instability. Results are OK.