huangyhg

picnic shelter
consider an open structure (picnic shelter)
should the roof be considered as an overhang for calculating the wind load pressure by the asce7-98 procedure?
or what is the true definition of an "overhang" in asce7-98?
thanks.
v2
we just faced that decision on a swimming pool bathhouse where a portion of the bathhouse had a large roof overhang - we opted to go with the overhang uplift pressure - we just felt that we could visualize a high wind sending the 15 feet of roof sky high.
v2...i look at those in two different ways. in one, i use the approach jae mentioned. another, if the roof is flat, i use the "open structure, monoslope roof" approach. the second approach does not consider overhang. it's a judgment call, and it doesn't hurt to be conservative! if the shelter is contiguous with another structure, use the overhang approach whether flat or not.
yes, i'd agree with ron - our project was a complete building with a portion (about 15' x 70') that was really an overhang even though it was a simple extension of the roof.
for a completely open building - some kind of monoslope system would be appropriate - the primary failure is really a straight-upward suction.
by the way, ron - working late on a sunday?
jae..if i stay away from it too long, i have to be retrained!
also, jae...you're post was obviously after mine, so that would probably put you in my same boat! be afraid...be very afraid!
people, thanks.
just to let you know, the shelter is on its own structure not associated with any other building. and the shelter has a 5/12 hip roof slope.
oh by the way, i can visualize it flying too.
v2
ron, so what you're saying is that engineering is nothing like riding a bicycle. once your off....you cannot get back on!?
re: sunday night - i was here but not working (getting my son familiarized with autocadd for a summer job).
jae..you bet!
keep in mind there are probably laws against exposing young minds to this screwy profession, although if he's like his dad, we can use all we can get!
well...gulp.....he's going into architecture.
i think he'll be a good one as he's already slamming engineers!

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