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AlexS_2013
Posts: 25
Registered: ‎09-16-2013
Accepted Solution

Applying concentrated wind loads

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09-17-2013 02:13 PM

Hi everyone,

 

I have a model of high-rise building. I need to apply 3 concentrated loads (Fx, Fy, Mz) to each slab of the building (wind loads).

In etabs I can assign rigid diaphragm to all levels and then apply loads in spreadsheet. They will then be distributed to other elements based on their stiffness.

 

Is there anything simillar in Robot? If yes, what is the best and fastest way to do that? All slabs are assumed to be rigid in XY plane.

 

Thanks

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Rafal.Gaweda
Posts: 4,935
Registered: ‎04-26-2010

Re: Applying concentrated wind loads

09-18-2013 12:43 AM in reply to: AlexS_2013
Available on 2014 SP2 this way: http://screencast.com/t/TibCCr9qPu
(you have to ignore instabilities reported in these added nodes)


Rafal Gaweda
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Contributor
AlexS_2013
Posts: 25
Registered: ‎09-16-2013

Re: Applying concentrated wind loads

09-18-2013 06:34 AM in reply to: Rafal.Gaweda

Thank you very much for the effort!

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

Re: Applying concentrated wind loads

09-18-2013 05:24 PM in reply to: AlexS_2013

Why 2014 SP2?  It works in 2013. 

 

Tony

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Rafal.Gaweda
Posts: 4,935
Registered: ‎04-26-2010

Re: Applying concentrated wind loads

09-18-2013 11:26 PM in reply to: tony.ridley
He has 2014 without SP. As far as I remember correction for merging nodes was introduced in SP2.
The same correction in last SP for 2013.


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

Re: Applying concentrated wind loads

09-19-2013 12:08 AM in reply to: Rafal.Gaweda
OK thanks
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Active Contributor
Kamikon-LK
Posts: 41
Registered: ‎07-17-2011

Re: Applying concentrated wind loads

09-19-2013 12:53 AM in reply to: Rafal.Gaweda

Nice, and is there a possibility to apply load to node on diafragm with the eccentricity?

Please find enclosed screenshots.eccentricity.png

 

eccentricity_EN.png

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Rafal.Gaweda
Posts: 4,935
Registered: ‎04-26-2010

Re: Applying concentrated wind loads

09-19-2013 02:07 AM in reply to: Kamikon-LK
Look at movie from post 2, do not apply load in added node , just connect this node with node with load by very stiff bar (like rigid link, but do not use rl) and check. If not - just calculate additional moments to the center of diaphragm and apply force + moments to this node.
NOTE: keep in mind that diaphragms work only in XY plane, so looking at your sketch this approach will not work. You will have to use ordinary rigid links.

Pozdrawiam


Rafal Gaweda
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Active Contributor
Kamikon-LK
Posts: 41
Registered: ‎07-17-2011

Re: Applying concentrated wind loads

09-19-2013 02:59 AM in reply to: Rafal.Gaweda

Nodal load not applied to cladding.

Why?

 

 

Dzięki!

Faktycznie użycie diafragmy w tym przypadku to zły pomysł.

Natomiast zrobiłem szybki test z okładziną i rozkładem obciążeń zamiast diafragmy, ale obciążenie punktowe nie jest  rozkładane. Z rozkładem obciążeń powierzchniowych czy liniowych nie mam problemów (no może czasmi :smileywink:), ale obciążenia punktowego nie udaje mi się przyłożyć do okładziny. W pomocy czytam, że jest to mozliwe:

"Do okładzin mogą być przykładane obciążenia powierzchniowe (jednorodne lub niejednorodne, definiowane na dowolnym konturze lub na obiekcie), liniowe (definiowane poprzez 2 punkty lub na krawędziach) oraz punktowe (siła w punkcie)."

W załączniku plik. Gdzie tkwi błąd?

 

 

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Rafal.Gaweda
Posts: 4,935
Registered: ‎04-26-2010

Re: Applying concentrated wind loads

09-19-2013 03:29 AM in reply to: Kamikon-LK

Wrong load type used - ther correct one is Load in Point (not Nodal Force).

 

Zly typ obciazenia. Poprawny ponizej.

 

sila.jpg



Rafal Gaweda
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