Z Purlin Design Tools 3

[zrck99]

I am needing to check some z purlins for bending and combined bending and axial loading. Does anyone have suggestions as far as tables or calculators that I could use to get this accomplished? The other guys that I work with typically run a channel shape in Enercalc and tweak the section properties to get closer to the properties of the z shape but if possible I would like to either hand calc with actual z purlin specific equations or use a z purlin specific calculator. Is there a code or spec that governs z purlin design and clearly covers the equations used for design?

Thanks in advance for any tips/suggestions.

ZRC

 

[ash060]

AISI S100 - Cold formed steel code. They have a manual that has design examples within it as well. I am assuming that you are talking about light-gauge steel purlins used in metal buildings and such. Light gauge is a much different design than your standard hot-rolled design. Several analysis programs, such as RISA 3D have light-gauge modules.

 

[dik]

Also look for a program called CUFSM.

Dik

 

[ajh1]

CFS produced by RGS Software is probably the best CF analysis package out there.

 

[hokie66]

We get a lot of questions like this on the site, and they all seem to come from North America. I think what you need are load tables like the ones in the attachment below. Trying to calculate purlin and girt capacities is very time consuming. The tables we use in Australia, where most commercial roof structures use these systems, are partly based on calculation, but are confirmed by load testing.

Your problem is likely due to the proliferation of "pre-engineered buildings" there, resulting in proprietary protection.

Butler Manufacturing is now a subsidiary of Bluescope Steel, the Australian company responsible for the load tables attached. Perhaps engineers in the US can put pressure on to make the purlin and girt systems into commodities, similar to your open web steel joists.

http://www.cadtech.com.au/Products/LYSAGHT/Zeds_Cees_Manual.pdf

 

[robyengIT]

may be this too

https://mega.nz/#!hd1izBLR!m8Iuanx6xhlKlKkzF0Vs5uTXxbCCoMeF0STvh7uoOu0

 

[dik]

Great links, thanks... Should have added that my Italian is not great, but, the numeric information is there.

Dik

 

[robyengIT]

Welcome Dik : I usually pick-up from Your suggestion too. If needed I am ready to translate the main headers

 

[dik]

Roby... data appears to be in English... or maybe metric <G>.

Dik

 

[hokie66]

dik,
If you need help in translating the Aussie reference, I may be able to help with that.

 

[dik]

Thanks hokie... once you get passed the accent, it's almost like English...

Dik

 

[robyengIT]

just for Dik (language : data in italian dialect)

https://mega.nz/#!MAsUlAwR!gQ7wvt6f5LQcQXdxEd6RLgCNLy90yyNH1tx2apZeL0Q

 

[ajh1]

The challenge with load tables is that as soon as you get non-uniform bay spacing coupled with partial / patterned load conditions the tables get too voluminous to maintain. Butler used to have load tables when all we made were 20', 25', and 30' bays. Today almost anything goes as architects get crazy.

 

[hokie66]

ajh1,
We've got crazy architects in Australia as well. And we don't even have any standardized buildings. We work with load tables, just using our engineering judgment and conservatism.

 

[zrck99]

Thanks for all the comments. I've scoured the web and can't find any span tables with English units. Frustrating. Are we unique in having Pre-Engineered Buildings here in the states? I'm wondering why the metric tables are available but not English. Maybe just not worth the companies time to put together the English tables?