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Contributor
luzer333
Posts: 13
Registered: ‎01-10-2013
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Modeling a Curved Roof

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02-15-2013 11:51 AM

Hello,

 

I'm trying to find a way to model a curved roof which would consist of several bended I-section beams. I would try Object Bending option however I cannot see such an option in the Edit menu (please see the attachment) eventhough the Solid Modeler is enabled.

 

I guess I can use the option Extrude Along Polyline however I don't prefer to bother with solids when there is a chance to use I-sections and analyse in Steel Design.

 

Can someone please tell me why the Solid Modeller options below Face offsetting as in the following link are missing for my version (I'm using RSA2013)? Also any ideas about how to model a curved roof under these circumstances are welcome.

 

P.S.: I tried both with Volumetric Structure Design and Shell Design Modules, no results.

 

http://docs.autodesk.com/RSA/2012/ENU/filesROBOT/GUID-6D12CC11-17B2-41B6-AD0D-2151F7D0935-418.htm

 

Thanks.

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Distinguished Contributor
mpcloob
Posts: 126
Registered: ‎12-11-2012

Re: Modeling a Curved Roof

02-15-2013 11:20 PM in reply to: luzer333

in the name of  GOD .

 

hello luzer

 

for modeling roof above your shape you should go to shell design in the first step and then follow numbers in attached image1 and then image 2.

 

if you can model a roof above your shape plaese prees button 'Accept as solution' below my answer.

 

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Artur.Kosakowski
Posts: 4,965
Registered: ‎12-17-2010

Re: Modeling a Curved Roof

02-18-2013 12:09 AM in reply to: luzer333

Could you attach the sketch of your roof?

In general any curve shape of a beam should be approximated by number of straight bars. You can use the steps shown below:

 

curved beam.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
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Contributor
luzer333
Posts: 13
Registered: ‎01-10-2013

Re: Modeling a Curved Roof

02-18-2013 03:01 AM in reply to: Artur.Kosakowski

Sorry I don't have any sketches of the model but the section view would look like your attached example. However if I model the roof that way, would the bending strenght of the whole beam overestimated because of the lenght of the each segment? As far as I know, Robot would analyse each segment by itself. For example if the whole beam is 30m in length and is divided into 10 parts, the bending moment would be applied onto 3m segments and bending strength would be found that way which would not reflect the exact reality. The only way to examine this kind of a model would be looking at the displacements of the nodes.

 

Your comments would be appriciated.

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Product Support
Artur.Kosakowski
Posts: 4,965
Registered: ‎12-17-2010

Re: Modeling a Curved Roof

02-18-2013 03:12 AM in reply to: luzer333

You can create a superbar (new member) for the steel design procedure that includes all the straight segments of the arch.

 

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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Contributor
luzer333
Posts: 13
Registered: ‎01-10-2013

Re: Modeling a Curved Roof

02-18-2013 05:21 AM in reply to: Artur.Kosakowski

That will satisfy my question, thanks a lot. For those who are looking for "superbar",

 

http://208.74.205.69/t5/Autodesk-Robot-Structural/Probl%C3%A8me-de-mod%C3%A9lisation-steel-design/td... (message 9, the attachment)

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Contributor
luzer333
Posts: 13
Registered: ‎01-10-2013

Re: Modeling a Curved Roof

02-19-2013 12:18 PM in reply to: Artur.Kosakowski

And do you have any ideas about why Object Bending option does not appear on the Edit menu?

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Artur.Kosakowski
Posts: 4,965
Registered: ‎12-17-2010

Re: Modeling a Curved Roof

02-20-2013 12:06 AM in reply to: luzer333

I'm sorry but I'm not sure if I understand you correctly. I'm not aware of any 'bending option' for bar elements.



Artur Kosakowski
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Contributor
luzer333
Posts: 13
Registered: ‎01-10-2013

Re: Modeling a Curved Roof

02-21-2013 04:21 AM in reply to: luzer333

"The current version of Robot lets you perform the following operations on objects using Solid Modeler:         

The quote is from the following link,

 

http://docs.autodesk.com/RSA/2012/ENU/filesROBOT/GUID-6D12CC11-17B2-41B6-AD0D-2151F7D0935-418.htm

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Product Support
Artur.Kosakowski
Posts: 4,965
Registered: ‎12-17-2010

Re: Modeling a Curved Roof

02-21-2013 04:43 AM in reply to: luzer333

This doesn't apply to linear elements (bars). The key word is solid :smileyhappy:



Artur Kosakowski
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