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Robot Structural Analysis

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Athi_uk
Posts: 13
Registered: ‎12-21-2010
Accepted Solution

Robot Steel Frame analysis

605 Views, 3 Replies
10-21-2011 02:33 AM

Hi,
Recently I have done a steel frame analysis in Robot 2011 and Can you please answer the following questions:
1. what is the default connections in Robot among the beams or beams and columns in a 3D frame?
2. Is it a rigid or pinned connection?
3. If I apply a pinned-pinned release among the bars structure becomes unstable during the calculation, how can I solve this issue?
4. Do we need to apply pinned-pinned releases among the bars when we do a frame analysis?

Many thanks

Regards,
James

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Product Support
Rafal.Gaweda
Posts: 5,173
Registered: ‎04-26-2010

Re: Robot Steel Frame analysis

10-21-2011 02:47 AM in reply to: Athi_uk

Hi

 

As a default all connections between bars are fixed.

 

In case of instabilities please upload model or contact me by Private Message



Rafal Gaweda
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Contributor
Athi_uk
Posts: 13
Registered: ‎12-21-2010

Re: Robot Steel Frame analysis

10-21-2011 02:57 AM in reply to: Rafal.Gaweda

Hi Rafal,

Thanks for your reply and I have attached the model with this message.

 

Regards,

James

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Product Support
Rafal.Gaweda
Posts: 5,173
Registered: ‎04-26-2010

Re: Robot Steel Frame analysis

10-21-2011 07:37 AM in reply to: Athi_uk

Hi,

 

Generally - too many releases (wrongly applied, giving instabilities - in this case errors in model).

You can not release bars on pinned supports (-> the same dofs released twice).

My vision of this model attached: fixed supports with released columns, bracings ( 101to108 128to137) as  truss bars, Fixed-Pinned1 releases applied on structure, some relases changed to get rid of instabilities.



Rafal Gaweda
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