Incorrect member forces in Robot after deleting part of the structure

[Anonymous]

I have a model of a steel structure that seems to be running correctly, meaning that the member forces and reactions make sense.

I deleted part of that model and all of the load cases, to have a partial model that reflects the up to date built structure on site. However, when running the calculations, some of the reactions and forces go crazy - say from 150 kN on the full structure up to 65457081 kN on the partial one.

I've had this problem before with other structures but found a way around it, however this time I have to make this specific one work.

Is there someone from Autodesk that can have a look at the Robot model and see what's going on?  Unfortunately I can't share that model here with all the users.

Thanks

Joao

[Rafal.Gaweda]

Please send us the file.

[Rafal.Gaweda]

You can not look at results if you have instabilities type 1 and 2 in model – you have to correct model first.

IN case of instabilities 3 you should check it and correct required

This may help you:

http://forums.autodesk.com/t5/Autodesk-Robot-Structural/API-macro-for-highlighting-nodes-with-instab...