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Robot Structural Analysis

Distinguished Contributor
Posts: 153
Registered: ‎09-14-2011
Accepted Solution

Grade Beam Design Question

628 Views, 1 Replies
04-09-2012 01:00 PM

I attached a really simple model for the purpose of checking the analytical results of hand calcs.  I wanted to check the robot design of the footings against my hand calcs.  That said, I can't even get the model to run.  I get a type 3 instability warning.  Any idea how to get this model to run?  Maybe I'm modeling grade beams wrong.

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Product Support
Posts: 5,471
Registered: ‎04-26-2010

Re: Grade Beam Design Question

04-10-2012 01:05 AM in reply to: bjur

Elastic ground acts only in local Z direction so you need to apply restraints in UX UY direction - example - green rectangles below


Ground beams are rotated upside down so  uplift in your case must me in the direction on -z


It may happen that some simple cases (with lateral loads) may not converge without vertical loads. Set thme as auxiliary cases and run calculations only for combinations containing these cases.


Corrected model attached.



Rafal Gaweda
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