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Dynamic degrees of freedom error

10 REPLIES 10
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Message 1 of 11
nvgeirinhas
1916 Views, 10 Replies

Dynamic degrees of freedom error

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

10 REPLIES 10
Message 2 of 11

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
Message 3 of 11

Hello

 

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

 

Best Regards

Nuno Geirinhas

Message 4 of 11

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
Message 5 of 11
nvgeirinhas
in reply to: nvgeirinhas

Hello, 

 

I send attach the file. 

Message 6 of 11

"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
Message 7 of 11

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

Tags (1)
Message 8 of 11

This needs to be addressed by the development team.



Artur Kosakowski
Message 9 of 11

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
Technical Account Specialist
Message 10 of 11
mjoflor
in reply to: Pawel.Pulak

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

Message 11 of 11

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

 

Corrected in SP3 for Robot 2015.

 

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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