Dome Design

[euranian]

I am going to design a dome for a church which are having copper panels on top of steel tubes. there will be about 8 tubes on which copper panel and the cross on top will be resting. The drawing shows the max. design dome weight (Dead load) shall not exceed 1200 lb. The Live Load from ASCE for curved roofs are 20psf. So does that mean only the dead weight should not exceed 1200 lb?. Because when I calculate using LRFD, even for the smallest HSS, the total shear value is exceeding 3000lb.
Kindly let me know how I need to Consider.

Thanks.

 

[ishvaaag]

Well, someone needs to be the designer of the dome (whomever, it may be you). Then, such designer needs to identify the extent of its commission, and if feasible within the asked limits or not. If the case of being (by reasonable and from code) standard that the thing seems to be unfeasible within the stated requirements, you need let the commissioner know about the problem and discuss with its competent representative the standing options. Upon your generic description I think a process on how go along with the issue I think more procedent than imaginative adivination of what kind of problem you are facing in quantitative terms, to speak of which, more data would be required.

 

[JStephen]

"the max. design dome weight (Dead load) shall not exceed 1200 lb."
"So does that mean only the dead weight should not exceed 1200 lb?"
That's what it sounds like from your statement, isn't it?

"Because when I calculate using LRFD"
"Dead load" would normally mean without the load factors included.