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New Member
Posts: 2
Registered: ‎08-30-2013

Cable Instabilities

135 Views, 4 Replies
08-30-2013 09:23 AM

I have a relatively simple cable model which has a horizontal cable supporting a series of vertical cables.  I have split the horizontal cable into a chain of smaller elements so there are nodes at the connections between the horizontal and vertical cables.  The assembly case works fine, with just the dead load of the elements themselves.

 

I wish to apply horizontal (lateral) loads to the vertical cables which will react onto the horizontal cable.  Whenever I do this, I get an instability of type 1 in the global Y direction which I don't really understand how I can overcome.  I could understand a rotional instability but not a directional one.

 

Any ideas?

 

Can't attach File as .rtd extension is not allowed?!

 

Tom.

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Moderator
Posts: 547
Registered: ‎05-09-2008

Re: Cable Instabilities

08-30-2013 01:31 PM in reply to: tomdilley

 

 

 


tomdilley wrote:

 

Can't attach File as .rtd extension is not allowed?!

 

Tom.


Try now. I just add the .rtd extension to the discussions.

 

Thanks
Discussion_Admin

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Artur.Kosakowski
Posts: 4,249
Registered: ‎12-17-2010

Re: Cable Instabilities

09-02-2013 12:17 AM in reply to: tomdilley

If a rtd file is too large try to zip it first. Otherwise check http://forums.autodesk.com/t5/Autodesk-Robot-Structural/Sending-bigger-files/td-p/3795062



Artur Kosakowski
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New Member
Posts: 2
Registered: ‎08-30-2013

Re: Cable Instabilities

09-03-2013 02:17 AM in reply to: tomdilley

Here is the file.

 

Thanks
Tom.

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Product Support
Artur.Kosakowski
Posts: 4,249
Registered: ‎12-17-2010

Re: Cable Instabilities

09-03-2013 03:16 AM in reply to: tomdilley

As far as I can see the instability is reported for case 2 in which there is no load defined. You have two options:

1. Delete case 2 

2. Set  P-Delta analysis for case 2 (as done for case 1). In such case the case 2 will be just case 1 which is the assembly one.

 

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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