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Active Member
nvgeirinhas
Posts: 8
Registered: ‎07-03-2012

Dynamic degrees of freedom error

867 Views, 10 Replies
02-14-2013 04:18 PM

Hello,

 

I have a structure, but when I run the calculations I have this error: "Number of dynamic degrees of freedom equals 0"

I think that is related to the application of the earthquake.

I can't solve it. Any suggestions?

 

Best Regards

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Artur.Kosakowski
Posts: 5,111
Registered: ‎12-17-2010

Re: Dynamic degrees of freedom error

02-14-2013 11:46 PM in reply to: nvgeirinhas

Most likely you defined supports in all nodes or you set 'disregard' density in the parameters of  the modal analysis without making any load to mass conversion. Otherwise I need the model to check.

 

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Artur Kosakowski
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Active Member
nvgeirinhas
Posts: 8
Registered: ‎07-03-2012

Re: Dynamic degrees of freedom error

02-17-2013 04:34 AM in reply to: Artur.Kosakowski

Hello

 

My parameters on modal analysis are this. Whow can I send the file to you?

 

Best Regards

Nuno Geirinhas

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Artur.Kosakowski
Posts: 5,111
Registered: ‎12-17-2010

Re: Dynamic degrees of freedom error

02-18-2013 12:32 AM in reply to: nvgeirinhas

Save the file with under a new name with no results and then compress it (*.zip). Then you can attach it to the post.

If it is too large use one of the free web services for file transfer and attach the link to download the file.



Artur Kosakowski
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Active Member
nvgeirinhas
Posts: 8
Registered: ‎07-03-2012

Re: Dynamic degrees of freedom error

02-18-2013 07:42 AM in reply to: nvgeirinhas

Hello, 

 

I send attach the file. 

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Product Support
Artur.Kosakowski
Posts: 5,111
Registered: ‎12-17-2010

Re: Dynamic degrees of freedom error

02-18-2013 07:51 AM in reply to: nvgeirinhas

"Most likely you defined supports in all nodes .."

 

Divide bars e.g. in this way:

 

bar division.PNG

 

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.



Artur Kosakowski
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Member
gabriel-razvan.cristian
Posts: 3
Registered: ‎06-11-2014

Re: Dynamic degrees of freedom error

06-12-2014 09:00 AM in reply to: nvgeirinhas

Hello Athur,

 

I have the same problem with the "Number of dynamic degrees of freedom equals 0.".

 

I try to divied the Edge 1 in more elements, but I still have this problem. My objectiv is to find the modal analysis of a dam.

 

Could you or somebody help me please to solve this issue?

 

Thanks in advance,

 

Razvan

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Artur.Kosakowski
Posts: 5,111
Registered: ‎12-17-2010

Re: Dynamic degrees of freedom error

07-02-2014 04:03 AM in reply to: gabriel-razvan.cristian

This needs to be addressed by the development team.



Artur Kosakowski
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pp2008
Posts: 528
Registered: ‎06-23-2008

Re: Dynamic degrees of freedom error

07-02-2014 04:48 AM in reply to: Artur.Kosakowski

Some workaround may be replacing your plane strain model by volumetric one.

Attached the file where I converted your model to solid - 10 meter slice of the dam modeled, additional face supports added to make it coherent with plane strain constraints.

 

A have deleted the loads - it will be necesary to re-define them as surface loads.

I have also noticed that you attempted to convert water pressure load into masses. Usually considering the pressure of liquid in vibrations is not so simple - there were some references considering it in some other post on this forum.

 

Best regards,

 



Pawel Pulak
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Valued Contributor
mjoflor
Posts: 54
Registered: ‎04-14-2013

Re: Dynamic degrees of freedom error

07-05-2014 06:12 PM in reply to: pp2008

There is no load to mass conversion, it need for modal analysis, 

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