Applying concentrated wind loads

[AlexS_2013]

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

[Rafal.Gaweda · Accepted solution]

Available on 2014 SP2 this way: http://screencast.com/t/TibCCr9qPu
(you have to ignore instabilities reported in these added nodes)

[AlexS_2013]

Thank you very much for the effort!

[tony.ridley]

Why 2014 SP2?  It works in 2013. 

Tony

[Rafal.Gaweda]

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.

[tony.ridley]

OK thanks

[KamikonLK]

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

Please find enclosed screenshots.

[Rafal.Gaweda]

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

[KamikonLK]

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 ), 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?

[Rafal.Gaweda]

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

Zly typ obciazenia. Poprawny ponizej.

[KamikonLK]

How the point load is distibuted on claddings?

Like on screen shot below?

Super! Dziękuję bardzo!

Prosze jeszcze tylko o wyjśnienie sposobu rozkładu sił skupionych. Nie znalazłem jednoznacznego opisu w pomocy. Podejrzewam, że są rozkładane jak na poniższym schemacie z właczonymi siłami generowanymi automatycznie.

[Rafal.Gaweda]

Yes.

Tak.

[Tuctas]

  Hi,

  If the last 4 posts (actually the 3 of them) were in english (at least Rafal's reply) it will be quite usefull for someone who is interested about this issue...

[KamikonLK]

Sorry . I understand you, I also do not like all those posts in French at this forum.

[Tuctas]

Not so nice to know that you could write in English and you didn't ... I'll wait at least from Rafal to re-post his reply in English.

[tony.ridley]

GOOGLE TRANSLATE 🙂
http://translate.google.com/

not 100% but works OK

[Rafal.Gaweda]

Enjoy. Translations added.

[Rafal.Gaweda]

GOOGLE TRANSLATE 🙂
http://translate.google.com/

This way to understand french post on this forum, also vietnamese (tried once or twice :-)), russian ...

Not perfect but in 95% enough.

[Tuctas]

  Thanks Rafal, Tony