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Modeling a Curved Roof

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Message 1 of 21
luzer333
3104 Views, 20 Replies

Modeling a Curved Roof

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.

20 REPLIES 20
Message 2 of 21
mpcloob
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.

 

Message 3 of 21
Artur.Kosakowski
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
Message 4 of 21
luzer333
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.

Message 5 of 21
Artur.Kosakowski
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
Message 6 of 21
luzer333
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)

Message 7 of 21
luzer333
in reply to: Artur.Kosakowski

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

Message 8 of 21
Artur.Kosakowski
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
Message 9 of 21
luzer333
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

Message 10 of 21
Artur.Kosakowski
in reply to: luzer333

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



Artur Kosakowski
Message 11 of 21
luzer333
in reply to: luzer333

Yes but still the command doesn't show up even in the volumetric structure design module eventhough an object is sellected as you can see in the attachment of my first message. I don't use the solid modeller too often but just curious. 

Message 12 of 21
Artur.Kosakowski
in reply to: luzer333

Some of these options are available only for Robot versions manufactured by Robobat prior to its acquisition by Autodesk. They depend on the version of ACIS geometrical kernel.



Artur Kosakowski
Message 13 of 21
luzer333
in reply to: Artur.Kosakowski

Ok. Thanks for enlightening.

Message 14 of 21
DanQuang90
in reply to: luzer333

About Cone Roof, Please show me how i can model cone roof with Truncated Cone form!

Thanks

Message 15 of 21
Rafal.Gaweda
in reply to: DanQuang90

conetruncated.jpg



Rafal Gaweda
Message 16 of 21
mgaafar
in reply to: Rafal.Gaweda

So I am analysing a penstock reducer, which is basically a pipe that has a square openeing 2mx2m at one side and a circle 1.6m diameter in the other side and this pipe is 4m long.

since the face skinning (lofting) is not available in RSA now, does anyone know how to model that with refined FE size?

this pipe is burried with soil load on top in one load case and water pressure from inside as another load case.

Thanks.

Message 17 of 21
Rafal.Gaweda
in reply to: mgaafar
Message 18 of 21
mgaafar
in reply to: Rafal.Gaweda

No Rafal, Please find attached the shape I want to create.

 

REDUCER.png

Message 19 of 21
Rafal.Gaweda
in reply to: mgaafar

Example of extrusion with deformation:

 

 



Rafal Gaweda
Message 20 of 21
mgaafar
in reply to: Rafal.Gaweda

Thanks Rafal !!

much appreciated !!

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