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PaulGrimes2282
Posts: 41
Registered: ‎05-28-2012
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Reaction Mismatch - Check Val not equal to Zero

438 Views, 4 Replies
05-28-2012 05:18 AM

In my model the check value in the reactions case is greater than zero - i.e. the sum of the forces is greater than the sum of the reactions by around 7800kN (out of a total sum of forces of 72600kN). i am also getting horizontal reactions with no horizontal forces applied which don't sum to zero, and huge moments about pinned supports.

 

I am getting some nodal instabilities as pre-analysis warnings which shouldn't be unstable - all have at least one point of fixity. I also had a couple of nodal instabilities at pinned supports, where i have now used fixed supports to get rid of the instability.

 

I can't attach the model file as it is too large - is there another place that i can upload it adn link to?

 

Thanks!

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Rafal.Gaweda
Posts: 4,935
Registered: ‎04-26-2010

Re: Reaction Mismatch - Check Val not equal to Zero

05-28-2012 05:28 AM in reply to: PaulGrimes2282

Try wetransfer.com or filemail.com

If not I will create ftp for you



Rafal Gaweda
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PaulGrimes2282
Posts: 41
Registered: ‎05-28-2012

Re: Reaction Mismatch - Check Val not equal to Zero

05-28-2012 09:26 AM in reply to: Rafal.Gaweda
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Rafal.Gaweda
Posts: 4,935
Registered: ‎04-26-2010

Re: Reaction Mismatch - Check Val not equal to Zero

05-29-2012 02:20 AM in reply to: PaulGrimes2282

1. Do not use kinematic links.

2. Use recommended meshing parameters and correct meshes

 

Take a look at message 3 in this thread:

http://forums.autodesk.com/t5/Autodesk-Robot-Structural/Structure-verification/m-p/3334637/highlight...

 

After correcting coherence of meshes I think you should remove releases from columns 952 1424 or define them properly not producing instabilities in model

 

COrrected model:  http://wtrns.fr/ospazeccgHWsNg



Rafal Gaweda
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PaulGrimes2282
Posts: 41
Registered: ‎05-28-2012

Re: Reaction Mismatch - Check Val not equal to Zero

05-30-2012 02:30 AM in reply to: Rafal.Gaweda

Thank you so much for looking at this - I will have a check through the model ASAP - i'm off on holiday at the end of today, but will try and have a look before i go, otherwise i will have a look when i get back.

 

thanks again.

 

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