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Valued Mentor
tony.ridley
Posts: 652
Registered: ‎09-07-2011

Section Properties.

399 Views, 9 Replies
09-18-2013 07:03 PM

Hi guys, a few things today;

 

1.  Please can you explain / confirm the following terminology.

 

Ix  - Is this the torsional Constant ("J" in Australia)?

I_Omega - is this the warping constant ("Iw" in Australia)?  I guess it is, as units are mm6.

 

section properties.JPG

 

 

 

2.  Wishlist request.

Can we have the ability to scale Ix, Iy, Iz for user defined beam sections (i.e. created in section builder, then saved to user database), similar to the functionality that exists on RC beam definition?  Example;

 

reduced moment.JPG

 

Thanks,
Tony

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Product Support
Rafal.Gaweda
Posts: 4,924
Registered: ‎04-26-2010

Re: Section Properties.

09-18-2013 11:44 PM in reply to: tony.ridley

 

1.  Please can you explain / confirm the following terminology.

 

Ix  - Is this the torsional Constant ("J" in Australia)?

I_Omega - is this the warping constant ("Iw" in Australia)?  I guess it is, as units are mm6.

 

2x yes

http://docs.autodesk.com/RSAPRO/2014/ENU/filesROBOT/GUID-ACA8C802-9921-4E53-BE52-D5B71145AA17.htm

 

 

2.  Wishlist request.

Can we have the ability to scale Ix, Iy, Iz for user defined beam sections (i.e. created in section builder, then saved to user database), similar to the functionality that exists on RC beam definition?  Example;

 

write it here:

http://forums.autodesk.com/t5/Robot-Structural-Analysis/idb-p/93

 

task for you - small macro \ addin in API..... :-)



Rafal Gaweda
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Product Support
Rafal.Gaweda
Posts: 4,924
Registered: ‎04-26-2010

Re: Section Properties.

09-20-2013 12:37 AM in reply to: Rafal.Gaweda

task for you - small macro \ addin in API..... :-)


With API modification (in fact you have to copy properties to user defined section in Robot and modify them) you will loose section shape. So the best way : edit database by Section Database viewer, copy records, modify copied records as you like.



Rafal Gaweda
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Distinguished Contributor
Tuctas
Posts: 160
Registered: ‎10-10-2012

Re: Section Properties.

09-22-2013 12:22 AM in reply to: tony.ridley

 I had suggested once a way to use profiles with modified properties (as the way that other programes use too). I think that it will be usefull if the user could modify the properties of standard section profiles (either RC or Steel sections, less for timber) from the Inspector dialog box and that would affect only the analysis (while for the design all the properties won't be affected) just for the purposes of modelling-simulation.

  I don't know if the development team liked my suggestion..

 

  Regards.

   

   

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Product Support
Artur.Kosakowski
Posts: 4,541
Registered: ‎12-17-2010

Re: Section Properties.

10-11-2013 03:02 AM in reply to: Tuctas

For RC design that is already possible by modification of moments of inertia for selected section labels. For steel I hope you can use the solution proposed in http://forums.autodesk.com/t5/Robot-Structural-Analysis/Change-the-Moment-of-Inertia-of-a-Standard-S...

 

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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Distinguished Contributor
Tuctas
Posts: 160
Registered: ‎10-10-2012

Re: Section Properties.

10-11-2013 01:45 PM in reply to: tony.ridley
As concerns RC members, the way of modification I proposed is more general and it can be more easily used for different kind of modeling cases. For instance, if someone wants to give a specific value to the moment of inertia, until now he has to make the calculation manually in order to find the proper reducing factor and then assign it to the section label..
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Product Support
Artur.Kosakowski
Posts: 4,541
Registered: ‎12-17-2010

Re: Section Properties.

10-14-2013 12:38 AM in reply to: Tuctas

Indeed you need to divide these two numbers and enter the result rather than enter directly one of these numbers but I hope that is manageable :smileyhappy:



Artur Kosakowski
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Distinguished Contributor
Tuctas
Posts: 160
Registered: ‎10-10-2012

Re: Section Properties.

10-14-2013 05:57 AM in reply to: Artur.Kosakowski

  Dear Artur,

  This is not the only point that matters.. It is in many ways very usefull to be able to modify different kind of parameters and not only moments of inertia for the purposes of modeling-simulation of a structure (as it is for instance for parameters like Ax, Ay or whatever). Just for the analysis while for design the same parameters to be unmodified. Many other programs do that :smileyindifferent: 

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Artur.Kosakowski
Posts: 4,541
Registered: ‎12-17-2010

Re: Section Properties.

10-14-2013 06:06 AM in reply to: Tuctas

I  understand your point and what you proposed is on the wish list item. 

 

What you can do now is:

 

- for RC design modules (RC Beam, RC Column) you can use one section in a model and then change it inside the design module into another one of the same type for design/verification

- for steel design module you can use one section in the model and then create a design group with another section for the verification

 

Hope this helps.



Artur Kosakowski
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Distinguished Contributor
Tuctas
Posts: 160
Registered: ‎10-10-2012

Re: Section Properties.

10-14-2013 07:28 AM in reply to: Artur.Kosakowski
O.k Artur, thanks.
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