Wind loads on hanging ceiling 2

[Daniel Roberto Morales Contrer]

hello to everyone this is my first post am glad to be part of the community , i have to check a hanging ceiling it will be attached to a slab concrete by a lot of ø3/8 RB Vertical rods, i need help with the calculation of the uplift wind pressure on that zone i will attach a photo, the blue lines represents the ceiling and the rods, the red arrow represents the wind direction and the green arrows repressents the wind pressure, i have been studying the components and claddings chapter on ASCE 7-16 but i am not sure

thanks!

 

[DaveAtkins]

You are on the right track. This has always been confusing for structural engineers. Is this an overhang? Or is it an open structure? I have typically considered it a building overhang, but I look forward to what others have to say.

DaveAtkins

 

[DanKile]

What you are looking at is a soffit. In ASCE 7-10 Figs. 30.7-2 & 30.10-1, soffit pressure is the same as adjacent wall. I would only use overhang pressures if the member has wind acting on both the top and bottom.

 

[Daniel Roberto Morales Contrer]

Thanks both for your replies,Dave Atkins and DanKile, so just to be sure about it, the ceiling we are going to install is based on W Sandwish Panels,and it will be attached to masonry walls at the perimeter, overhang pressures are used when wind loads acts on the top and bottom surfaces, i think that in my case the wind will act only on the bottom surface because of the seal between the walls and the ceiling at the perimeter, so the correct load to use here is the windward on the adjacent wall? correct me if iam wrong

Thanks!

 

[DanKile]

You'll want to look at both the positive and negative wall pressure (windward and leeward).

And dead load will work against the uplift (positive wall) and with the suction (negative wall).

 

[Daniel Roberto Morales Contrer]

Great Dankile, with this i can continue thanks a lot!

 

[Enable]

Does the system manufacturer have a UL 580 rating for their system? If they do maybe it's enough just to look at the rating and go "meh probably good enough". The last system I did like this provided compression post spacing for a UL 580 class 90. Don't know what ASCE-7 says about this though as it's not my code.

 

[DanKile]

UL 580 Class 90 is a certification that the assembly listed can support at least 90psf negative pressure (away from structure).

ASCE-7 just tells you the minimum loading to be applied, not how strong members are.

 

[Enable]

I was trying to suggest that if based on the OP's experience with ASCE-7 the pressures are likely to come out a lot less than the UL rating or some other equivalent rating on the system (regardless of which interpretation / figure is supposed to apply) - say based on their knowledge of typical worst case negative pressures on a single story build in the area - then they could get on with the business and sleep soundly at night. It was more of a comment re: how to get it off their desk in case that was what they really needed.