Wind Load on 3-Wall Metal Bldg

[labeattie]

Hi all,

I was designing an open pavilion structure (monoslope roof) for uplift using ASCE 7 Fig 27.4-4, only to find it has been decided that the building will have wall panels on the sides and back. To me this just looks like a parachute for wind, and the uplift and overturning forces should increase by more than simply adding a wind pressure meant for an external wall. If anyone knows how to get the loads for this (specifically wind loads for the wind direction blowing into the building), then your help or recommendations would be appreciated. I attached a picture in case there's any confusion as to the type of building I'm talking about.

Thanks,
labeattie

 

[msquared48]

No picture...

Mike McCann, PE, SE (WA)

 

[labeattie]

Sorry... first time attaching a picture. I have the engineering.com url in both the attachment field and below this time. If this still doesn't work, I also wouldn't mind advice on how to attach a photo

http://files.engineering.com/getfil...6281-46b7-a98d-77f1ac850b96&file=barnshed.jpg

 

[JoshH726]

Have you considered obstructed wind flow on the roof in addition to the wall pressures? The coefficients for obstructed wind flow generate plenty of uplift for the roof.

 

[labeattie]

Yes. I considered all cases from ASCE 7 Fig 27.4-4. If I'm not mistaken, though, that still is planning on letting the air that flows under the roof escape. It just runs into the wall and has to stop (and possibly then create more uplift) in my situation. If I'm wrong though, and that's the kind of situation the obstructed coefficients were intended for, then I'd be happy to know that.

 

[manstrom]

The GCpi value should be big and additive to the regular pressure. It should be regular pressure plus 0.55 (?) times the q value.

When I am working on a problem, I never think about beauty but when I have finished, if the solution is not beautiful, I know it is wrong.

-R. Buckminster Fuller

 

[labeattie]

I think that's exactly what i needed. Thanks! I must've overlooked that coefficient in being used to the open building calculation.

 

[SAIL3]

a rough sketch with dimensions would help.....also type of fdn that is going to be used as the wind cases for max loads on parts of the structure may not result in max load on an individual footing....I would expect numerous wind load cases....

 

[PSEPK]

Metal Building Systems Manual by MBMA provides several detailed examples for calculating wind loads for many other type of buildings, including the one shown in your attached picture.

 

[SKJ25POL]

PSEPK (Structural),
Can you please attach the coversheet of the docyument you stated.
I would like to purchase it but I don't what is the exact title of the document, where I can buy it directly if it cannot be shared.

I appreciate your assistance.

Regards,

 

[jayrod12]

google is your friend, my friend.

http://www.mbmamanual.com/products/13-2012-metal-building-systems-manual.aspx

 

[Archie264]

Out of curiosity, what is the building's height and bay widths?

 

[labeattie]

The buildings low side height is 16', and is 25'x100' with 20' bays and a 1:12 roof. I appreciate everyone's help and the reference recommendation. This is a very preliminary design though, and i really just wanted to know how to account for building being partially open rather than open or closed, which was right in the ASCE 7 code. I must've just glossed over it, heading straight for the equations I've used on open and closed structures. Thanks!

 

[SKJ25POL]

jayrod12 (Structural)
Thank you very much, I appreciate it.
I found it. Again thank you so much. (I am a new engineer.)

Have a good Thanks giving.
Regards.