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Valued Contributor
pevelor
Posts: 92
Registered: ‎12-12-2011
Accepted Solution

Structure verification

2385 Views, 9 Replies
02-16-2012 12:03 AM

Hi 

 

I transferred a file from revit and ran structure verification without any errors or warnings.

However, after meshing (haven't done anything else in between) I get an error which is "No material" and a warning which is " Incoherent mesh on edges".

 

I tried re-mashing the panels without any luck.

 

My questions are,

- What is the reason for this error, since I didn't get it on the initial verification?

- Is there any general rule for which settings should be used for meshing?

- What is the procedure to fix errors and warnings?

 

In addition, I've read the following post

http://forums.autodesk.com/t5/Autodesk-Robot-Structural/T-slab/m-p/3185418#M915

which displays a discrepancy in regards to the getting started guide (offset definition pp109)

Which is to prefer?

 

Lastly, I've read a lot of threads regarding releases lately.

As I understand, there should be some constraints at all support nodes. What is the release by default, and should these be changed or be keep the same?

 

In advance, thanks a million.

 

regards

Peder

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Valued Mentor
tony.ridley
Posts: 636
Registered: ‎09-07-2011

Re: Structure verification

02-16-2012 01:58 AM in reply to: pevelor

Pevelor,

 

Just run the analysis.  Then the error about no material will disappear if you do the verification again.  

 

As far as meshing goes, the reason you get incoherent mesh is due to small (even tiny) variation in panel geometry (happens alot with revit export).  See the image attached for panel 55.  Its slightly off the line where the two panels on top meet.  So it's better to try and get the geometry correct first.

 

wall 55.jpg

 

 

 

 Just choose some different mesh options until it looks like a nice clean mesh.  You have to balance density of mesh with accuracy of results and calculation time.  

 

You'll probably find if you just run the analysis and then do another verification you will get a warning about incoherent mesh and kinematic constraints.  Try setting the mesh options in job preferences to iterative, rather than kinematic.  

 

mesh parameters.jpg

 

As far as chasing down and fixing errors, just go step at a time.  

Support degrees of freedom are up to the engineer to choose based on anticipated real fixity conditions, no one can make that recommendation for you.  :smileyvery-happy:

 

 

Good luck,

 

Tony

 

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Product Support
Posts: 4,445
Registered: ‎04-26-2010

Re: Structure verification

02-16-2012 02:16 AM in reply to: pevelor

I transferred a file from revit and ran structure verification without any errors or warnings.

However, after meshing (haven't done anything else in between) I get an error which is "No material" and a warning which is " Incoherent mesh on edges".

 

I tried re-mashing the panels without any luck.

 

My questions are,

- What is the reason for this error, since I didn't get it on the initial verification?

 

Make settings like this:

 

Turn off kinematic links, use Iterative adjustment 

 

kinem.jpg

 

(gryed out field settings also important ; element size  - up to you)

 

mesh.JPG

 

- What is the procedure to fix errors and warnings?

 

After above changes ther is only one error in your model :

move indicated point by drag and grop to new location - click on this point \ cross twice (not doubleclick) and drag it to new location

 

err 41 44.jpg

 

Corrected file attached.

 

In addition, I've read the following post

http://forums.autodesk.com/t5/Autodesk-Robot-Structural/T-slab/m-p/3185418#M915

which displays a discrepancy in regards to the getting started guide (offset definition pp109)

Which is to prefer?

 

Decision is yours.

 

Lastly, I've read a lot of threads regarding releases lately.

As I understand, there should be some constraints at all support nodes. What is the release by default, and should these be changed or be keep the same?

 


As a default in robot all connections between elements are fixed.

In Revit - it depends on seetings in Revit - usually all are pinned but in your model (at least in the robot model you sent all of them are fixed). So if you need releases on bars please assign them.



Rafal Gaweda
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Valued Contributor
pevelor
Posts: 92
Registered: ‎12-12-2011

Re: Structure verification

02-16-2012 03:53 AM in reply to: Rafal.Gaweda

awesome, worked perfectly

 

Thanks again.

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Valued Contributor
Posts: 81
Registered: ‎08-02-2012

Re: Structure verification

09-25-2012 06:20 AM in reply to: tony.ridley

Afternoon All,

 

I'm trying to track down an "incoherent mesh" error, however when selecting the error the offending panel is not highlighted. What display settings need to be selected to highlight it?I have switched off all "mark with colours" display options. Nothing is highlighted.

 

Trying to track down this form of error when nothing is highlighted is like a needle in a haystack!

 

Thanks in advance,

Scott

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Valued Mentor
tony.ridley
Posts: 636
Registered: ‎09-07-2011

Re: Structure verification

09-25-2012 06:29 AM in reply to: Opel5

It does not highlight the panel.  It highlights the nodes as a blue "line", and the FE's go red outline.

 

Cheers,

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Valued Contributor
Posts: 81
Registered: ‎08-02-2012

Re: Structure verification

09-25-2012 07:00 AM in reply to: tony.ridley

Hi Tony,

Yep that's the problem I'm having, the FE's are not highlighting red so it's a complete guess as to which area of the building the error is trying to point to. I've tried tweaking the display settings but can't seem to find a combination which enables the highlight. Any advice is greatly appreaciated!

Thanks,

Scott

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Product Support
Posts: 4,445
Registered: ‎04-26-2010

Re: Structure verification

09-25-2012 07:22 AM in reply to: Opel5

Movie: http://screencast.com/t/43zhRBem



Rafal Gaweda
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New Member
Posts: 2
Registered: ‎01-23-2013

Re: Structure verification

06-17-2013 10:39 AM in reply to: Rafal.Gaweda

Hi Rafal,

 

I have a similar problem. Originally I created these panels in Rhino and then exported as a .sat file and opened in Robot. This has given me the problems described here, so I redrew the panels in Robot from .dxf bars. I've made the changes you highlighted, but as soon as I mesh my panels forget what they are made out of and tell me there is no material. This is getting extremely frustrating!

 

Please could you take a look at my file and see if you can figure out what's happening?

 

Thanks,

 

Matt

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Product Support
Posts: 4,445
Registered: ‎04-26-2010

Re: Structure verification

06-18-2013 12:31 AM in reply to: MattH37

 tell me there is no material. 

 

 

It is corect. Meshing does not apply any properties to FEs. To do so you have to run Model Generation or Calcaultions.

 

Some remarks:

- do not use kinematic links

-  panels 146 156  are not defined in the same plane and you may get error about Incoherent mesh. To overcome it please set model gemeration tolerance = 1mm



Rafal Gaweda
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