Wind loadings on a highly irregular plan layout...

[youngstructural]

Morning All;

Just want some opinions on how to handle a highly irregular plan layout when it comes to wind loadings. Basically I'm looking at a plan that looks like six individual buildings corner to corner, or sometimes overlapping a couple of meters. The "buildings" vary from 10mx15m to 16mx20m. Do you treat the individual portions of the structure as unique buildings that are adjacent, or would you simplify the situation and treat it as one large overall building? I'm leaning towards individual treatment, as I feel this better matches the spirit of the code (after all, don't we often build next to existing structures in effect creating the same situation?). I would, however, like some opinions.

Thanks in advance,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...

 

[csd72]

You are on the right track.

You need to treat them as individual rectangular buildings to a certain extent, but keep in mind that some factors increase with increasing distance along the roof so you need to allow for the worst case.

I would basically design bracing/racking for each individual rectangle also (as much as practicable).

The rectangles that I use would be different in each of the 2 perpendicular directions.

 

[youngstructural]

Thanks csd72; that confirms exactly my approach. I appreciate the thoughts...

Cheers,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...

 

[haynewp]

I would mention getting a wind tunnel test done, though for a small project it may cost several times more than the engineering fee. But this way you can say you at least brought up the idea if the cladding blows in. The problem is that wind codes are not meant to be applied for such a situation. I have just done the best I can when I had to apply wind provisions to a situation like this where they really didn't fit. And was a little more conservative.

 

[csd72]

haynewp,

This day and age there is no such thing as a plain rectangular building, so according to your advice you would have to wind tunnel almost everything!

If the building can be divided up into rectangular areas that basically meet the code then there is no reason not to do it that way.

Regards

csd

 

[haynewp]

csd72;

Yeah you are right. Just do whatever you want. Whatever you think "basically meet the code" means.

 

[csd72]

haynewp,

you caught me there on my 'basically meet the code'. I was not proposing to purposely design a code violation, but the code is a bit vague on what is irregular and that grey line was what I was referring to.

It is a good point to be a bit conservative on cladding loads, but I cant see that overall MWFRS loads would vary that much between rectangular buildings.

Regards

csd