Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Register Log in
  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

ASCE 7-05 - Vertical overhang pressures on leeward wind

Status
Not open for further replies.
campbelltc

campbelltc

Structural
Sep 21, 2011
22
It may not end up making any difference in the design, but I am designing supports for two canopies hanging off the side of a low rise building (4' wide x 16' long and 8' wide x 12' long). I'll design the canopies for the uplift on an overhang, and I know the uplift on an overhang is due to windward wind hitting the surface and channeling upward. Does the opposite happen on the leeward (suction) side? Is it a downward force? An upward force? Just a force parallel to the canopy? Thanks for your knowledge and opinions.
 
Replies continue below

Recommended for you

Sort by date Sort by votes
On the leeward side, my understanding is that there would be the usual suction (uplift) force, normal to the canopy surface. There is also the possibility of a downward load, but that usually comes out to less than the minimum 10psf design load, for most cases around these parts.

Thaidavid
 
Upvote 0 Downvote
Why not use components and cladding simplified table for Zone 2 and 3 overhangs? Negative magnitudes indicate uplift. Adjust for importance and exposure.
Capture_oce73x.png


Juston Fluckey, SE, PE, AWS CWI
Engineering Consultant
 
Upvote 0 Downvote
If your question wasn't on the how (you said you were going to design it for the overhang) and more on the academia of the wind behavior, I would point out Method 2 of the C&C does not give a positive GCp for overhangs like it does for the non-overhang zones. You are always looking at an uplift force regardless of windward/leeward. However, this figure does not indicate if there is a difference in magnitude and which side is controlling. I would think the leeward side provides the worst-case results though.
Capture_at6r2d.png


Juston Fluckey, SE, PE, AWS CWI
Engineering Consultant
 
Upvote 0 Downvote
ASCE 7-10 sheds more light:
Capture_sty52d.png


Juston Fluckey, SE, PE, AWS CWI
Engineering Consultant
 
Upvote 0 Downvote
Status
Not open for further replies.

Similar threads

canwesteng
  • Locked
  • Question
ASCE 7-05 Simplified wind procedure
Replies
8
Views
280
lexpatrie
lexpatrie
masterdesign
  • Locked
  • Question
ASCE 7 wind pressure on overhangs
Replies
9
Views
579
lexpatrie
lexpatrie
tmgczb
  • Question
How is wind speed or pressure converted calibrated based on ASCE 7/05/10/16, for API 650?
Replies
0
Views
177
tmgczb
tmgczb
LoadSlayer
  • Locked
  • Question
ASCE 7 Wind load
Replies
5
Views
401
LoadSlayer
LoadSlayer
Larryhd2
  • Question
ASCE 7-16 vs 7-22... use higher Sds?
Replies
7
Views
1K
Aesur
Aesur

Part and Inventory Search

Sponsor

Back
Top Bottom