Aluminum Diaphragm and Shear Walls

[pmblair]

I am having a hard time finding on design values for aluminum decking as a diaphragm and/or a shear wall material.

I recently started designing Storage Sheds and the typical industry roof deck and siding is aluminum. I am looking for some design values for shear strength as a diaphragm and shear wall.

Thanks,

 

[MiketheEngineer]

Call the mfg. If they haven't or can't provide values - then find someone who can.

It really depends a lot on the screw patterns, girts, trusses, purlins, whatever makes up the diaphragm. The "good" companies spend the time and money to provide such answers.

Steel guys do it all the time!!

 

[Ron]

Agree with Mike, and add that aluminum sheet is a completely different alloy than structural members. It has relatively low strength and is so thin in these applications I would probably not consider diaphragm.

 

[pmblair]

Thanks guys, that is what i expected, but was hoping for some link to some data.

I typically design commercial structures and recently was offered to step on for an ailing elderly engineer who designs sheds and such.

These contractors are flipping out because i am changing "the way we have done it for 30 years" and "lets not reinvent the wheel".


The customers flip out over adding one screw to a connection, let alone changing the decks from aluminum to steel.

With as common as it appears in this market, I cant believe there isn't some data and testing on it.

 

[Ron]

pmblair...sheds get little attention from code officials. For that reason alone, poor practices, both in design and construction, have prevailed. It is hard, but not impossible to correct that.

 

[JoeBaseplate]

May be you can find some useful info in the Aluminum Design Manual by The Aluminum Association.

 

[ash060]

The ADM does not cover aluminum diaphragms, but they mention a reference

http://www.metalconstruction.org/pubs/index.cfm?pg=pubs_avail.htm

It is the primer on diaphragm design by the MCA

 

[MiketheEngineer]

And I hate to say it - they have been standing for thirty years.

With the code officials lacking work they are checking EVERYTHING!! In my county they are only working 4 days a week and take 2 or 3 weeks to get it through. In 2005 - it took about 3 days!!

When I get hit with that - I usually respond with -

"If you have been doing it that way for thirty years - you should know better by now."

OR -

"You should learned how to do it right by now."

Haven't gotten my teeth removed --- yet...

BTW - why not switch to steel? - usually much cheaper and the newer coatings come with some amazing guarantees...

 

[pmblair]

Thanks everyone.

I have the Aluminum Design Manual, but not the primer on diaphragm design by the MCA.

Does any one have this and can check if its worth the money. The only reason i would buy it is for the diaphragm and shear wall design in aluminum.

I also have "ALUMINUM STRUCTURES A Guide to Their Specifications
and Design Second Edition"

It references "While more research has been done on steel diaphragms than aluminum, Sharp (133) presented shear test results for corrugated and V-beam aluminum sheeting"

It actually has some test results that it tables from the "Sharp" reference but im not sure which book of Sharps it came from.

Hinkle, A. J., and M. L. Sharp, Load and Resistance Factor Design of Aluminum Structures, Alcoa Report No. 89-57-03, Alcoa Center, PA, February 1989.

Sharp, M. L., Behavior and Design of Aluminum Structures, McGraw-Hill, New York, 1993

Sharp, Maurice L., Glenn E. Nordmark, and Craig C. Menzemer, Fatigue Design of Aluminum Components and Structures, McGraw-Hill, Inc., New York, 1996.

Anybody have any of these and can look into them?

Thanks Again everyone....