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Unistrut P1000 (or other) esr report 1

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OUe

OUe

Structural
Feb 14, 2007
47
I'm working on a project in Anaheim, CA involving cable trays and unistruts. My boss, the structural principal at our firm, recently mentioned that we should mention the evaluation report since it's in California. Well, this put a monkey wrench in everything I was doing. Not only has this been done many times before (the project is in Disneyland) with the same client, but it's also an application (a channel strut) where I can't seem to find ANY manufacturer that provides a tested ICC report for a channel strut system. Can anyone help me on where I might find such a thing or if it's even needed?

Thanks,

OUe
 
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Good luck. Let us know if you find anything. You can get some old CA seals on strut technical info if you look for unistrut seismic but no testing reports.

Oddly, the strut capacities assume 42 ksi yield strength, but AISI would require specific member testing for strut shapes made from ASTM A653-33 steel to get above 39 ksi (by my calculations based on bend radii on the P1000 shape). Further, the max yield for a metal with Fu = 45 ksi, is 41.7 ksi (42?).
 
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I just searched the internet and ICC and found no references to Unistrut in any of their ESR's. What's with that?! How do you spec them on OSHPD jobs??
 
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I've used them for probably many more years than some of you have been around and never thought of this. In their literature they say that their member allowable loads are based on AISI. This doesn't help for the connectors, but is that enough for just the shapes?
 
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Teguci said:
Oddly, the strut capacities assume 42 ksi yield strength, but AISI would require specific member testing for strut shapes made from ASTM A653-33 steel to get above 39 ksi (by my calculations based on bend radii on the P1000 shape). Further, the max yield for a metal with Fu = 45 ksi, is 41.7 ksi (42?).
Click to expand...

Did you include the little reverse 180 bend length inside in that theoretical calc for strength?

These have been standard for electrical and instrument mounts for years - Why would there be questions now?
 
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I only question it because the building authorities question it and they hold the cards.
 
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They do not have an ICC- But they provide section properties so you can calc the capacities yourself. No ICC report needed then
 
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OUe:
What would happen if you actually designed the damn thing to do what it is supposed to do, instead of picking it out of a table? That’s what engineers used to be able to do, and did.
 
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Unfortunately, many Authorities Having Jurisdiction will require the reports regardless of engineering design.

But I have other fights to win right now.
 
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racookpe1978 said:
Did you include the little reverse 180 bend length inside in that theoretical calc for strength?
Click to expand...

It's actually 2 90-deg bends. Inside radii are, from the slot, 1/32", 3/32", 1/32", and then symmetry.

STRUT_PROPS_gaiu9d.jpg


41.7 ksi may be appropriate for the effective yield, but, in order to get there, someone needed to have done (and hopefully published) tension tests and stub column tests per AISI. In any case, don't forget the reduction factor for lateral bracing.
 
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dhengr - I guess if I didn't care if we made any money on the project, I would say that's a great idea (sigh). Call me lazy, but I'd love for them to have some kind of reporting in cad form like the fellow above has done. I'm not sure an FEA would be required where long-slotted holes are concerned (on 1 face or 3 faces), but that's another can of worms that little projects like these usually don't have in the proposal hours (if you catch my drift)...
 
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OP,

Has the jurisdiction commented on the need for ICC report yet or are you doing this preemptively? We do a lot of cable trays, ladder racks, and such here in California for OSHPD jobs and they usually don't questions the capacity of the structs themselves. They mainly comment on the bracing system, i.e. brace connections like the channel nut, expansion anchor to structure. For OSHPD projects, Mason Industries have an OPM approval from OSHPD for ducts and conduit seismic bracing. OPM 0043-13. Check that out and see if it helps.

Regards

DS
 
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Thank you dougseason. I try to make a preemptive effort to show it on the drawings. It can also be of help to the installer as the icc reports often have a few vital tips for installation (ie drill bit size for post-installed anchor, etc). Thanks for the info, nonetheless.
 
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You also have to apply a reduction factor based on hole pattern style.
 
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