Wind Load on Curved building 5

[StructFton]

I am designing a three storey curved building, and cannot locate a method to determine the overall wind pressure on the building.

Can someone please give me a reference (book, paper etc...) which would outline how to calculate the wind loads

thanks
Alex

 

[JStephen]

In the US, refer to ASCE 7 & your local building code. If not adequately defined by building codes, wind tunnel testing is a possibility if the project warrants it, which, if you're asking the question, it probably doesn't.

Outside the US- check building codes for your area.

 

[RFreund]

I'm not sure that ASCE7 address this situation and I really could not find much other info on this. One approach may be to use the arc length of the wall rather than the radius depending on how small the radius is or how far around the building 'wraps' around. Or even try treating it as a partially open structure, where wind enters the 'circle' but it is not 'free' to escape so you have this large "internal" pressure. Just a couple of thoughts.

Let us know if you find anything. Also what is the geometry of the building (approx radius, arc length, etc. )

EIT

http://www.HowToEngineer.com

 

[dcarr82775]

There is an old document, ASCE Paper 3269 "Wind Forces on Structures". It provides some additional detail on pressure distribution on round structures such as stacks that may be applicable. It uses the older fastest mile wind theories.

 

[CANPRO]

NBCC (National Building Code of Canada) Commentraries Part I, Fig I-27 has wind pressure coefficients for a curved roof.

Looking ASCE "Guide to the Use of the Wind Load Provisions" ASCE 7-02, there is an example (example 3.11) which deals with a Dome roof building. They say "The walls of a round building are not specfically covered by the Standard. The values for the force coefficents for round tanks and chimneys from Figure 6-19 are used to determine the effect of the wall pressures on the MWFRS."

The University of Toronto actually scanned and posted the NBCC 2005 section of the above mentioned commentaries....

http://www.google.ca/url?sa=t&rct=j...lls&source=web&cd=2&ved=0CC8QFjAB&url=http://

http://www.utoronto.ca/sheikh/Codes...2eoTnteO75Erzq7cqXNiXOQ&bvm=bv.47244034,d.aWc

 

[StructFton]

Hi All

Thanks for the advice. My main concern is not the round side, but the concave side when the wind is blowing perpendicular to it. See the attached sketch.

RFreund, I like you methodology, but was hoping for something more exact.

I was thinking to dust off my fluid dynamics text to see if it would have anything.

Does anyone have a book/article that will adress this loading situation?
thanks

 

[TDIengineer]

In looking at the size of the footprint and the curved being relatively flat, I would just straighten out the curved shape and design for a long rectangle and that project area.. That would be conservative and increase your lateral load at that cupped side.

 

[TLycan]

Totally agree with TDIengineer