Houseguy:
After thinking about it a bit more I think I agree with you and I think I'll redesign each rafter frame to take it's own tributary width (16") rather then assuming that a roof diaphragm will take the shear to the gable end walls.
The STAAD model I used has a hinge in the rafter where...
I have a similar situation only I have a roof truss that cantilevers 6' beyond the bearing/shearwall. Thus, there is a 3' gap between the top of the shearwall and the top of the truss.
Now, for the roof diaphragm to work correctly the shear has to come out of the sheathing and go into the wall...
Never seen one. The ASCE07 as well as Breyer's book on wood design have some good data on typical building material weights and I'm sure you could rough something with that.
MightyPirate, EIT
Oh, and contact your local simpson supplier for quotes on the cost difference. If it's only a few connectors then it wont be much, otherwise it could get expensive.
Here's a good site to look at:
http://www.nadra.org/industry_news/acqarticle.html
Also, check out the American Wood Protection Association page:
http://www.awpa.com/
My understanding is that most PT lumber should have hot dipped galv. (HDG) connectors at a min. but that significant corrosion...
From what I remember off the top of my head, yes, they assume one bolt is installed before the other and thus the different clearances.
Have you checked the AISC commentary?
MightyPirate, EIT
msquared48:
Just an FYI, after modeling the structure in STAAD I came up that a single 2x8 A-Frame at the gable ends can take the tension force of 5016 lb (at the base) and shear force of 1773 lb (at the peak) from the wind loads on the roof diaphragm.
So, anchor the base using a beefy simpson...
I learned a lot of my drawing skills in College and picked up the rest in the field but I would suggest doing what JedClapett said, just grab a set of drawings and sit down with it. A computer helps as well as most of the acronyms can be googled.
Are you looking for just section properties or actual design information? I know that some old AISC books and bethleham steel books have Z sections in them.
-MightyPirate, EIT
Huh, didn't know that about the old greenboard, good to know though (it's what I have in my house).
Anyway, after very quickly reading GP's page on Densshield board it seems that Densshield qualifies under the 2006 IBC as a direct 1:1 substitute for gypsum wallboard.
Just off the top of my...
Have you tried contacting the manufacturer of the cement board? They might have information on using their product as a braced shearwall panel.
Also, you could just spec out water-resistant gypsum wallboard (green board) and the tile installers shouldn't have a problem.
MightyPirate, EIT
Thanks msquared48, I'll check that. I was talking around the office and that seems to be the consensus as well. The only problem is that the roof rafters are 38' long and are not continuous but I think the chord forces will be small enough that I can get a splice to work for those.
No...
My recent project is designing a 3-story A-Frame structure in a high wind area (lake front). In addition the front and rear transverse walls are packed with windows.
So, my question is there literature regarding the design of A-Frame buildings? Mainly I'm looking for information on the...
The only thing I could think to add is that if you do reuse them make sure that the threads are oiled properly each time or it wont pretension properly with each re-use. I remember seeing this tip in an AISC magazine.
-MightyPirate, EIT