Supporting Steel Angle From Steel Roof Deck 1

[ChiEngr]

Hello,

I am trying to laterally brace an HSS column to the underside of steel roof deck (wide rib deck) via bearing against the vertical leg of steel angles on each side of the column. I am wondering if anybody has ever pre-drilled holes into the horizontal leg of an angle and fastened the angle to the deck, across say (4) ribs, with self-tapping screws. I have only ever connected thin steel to thick steel, not the other way around.

Thanks in advance for your help.

 

[KootK]

We've discussed this here before, I know. It comes up a lot in retrofit applications. My recollection is that Hilti has fasteners appropriate for this situation. I'd give them a call.

You didn't ask for detailing suggestions but, if I understand your situation correctly, My preference for something like this would be to run a length of C10 on the flat for a stretch off of the column and attached the deck to that. This doesn't change the fundamental problem of course. You could also fasten/weld some sheet steel to the channel and then screw that sheet steel to the deck.

 

[XR250]

I don't see why you could not do that as long as the holes are pre-drilled.
I would somehow fasten the angles together so there is only shear and dead load tension on your roof connection (no prying forces)
I did a similar connection for some really tall 6x6 wood posts in a Crossfit Gym for their pull-up racks.

 

[ChiEngr]

Thanks for the input Koot and XR!

I will give Hilti a call just to see if there are indeed specific anchors for this scenario.

 

[KootK]

Report back if I wind up not being full of shit on the Hilti thing. I could use a refresh on this.

 

[ChiEngr]

@KootK

I am sorry for taking so long to follow up on this. I called Hilti, and the rep said that she was not aware of any particular fastener other than screws or PAFs in pre-drilled holes. I just wanted to close the loop on this discussion. Thanks again for your input!

 

[dik]

Catch the copy...This came up on a recent project where the consultant was wanting to secure angles to the top of steel deck...

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1669669573/tips/Hilti_Fasteners_wmc37i.pdf[/url]

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[KootK]

Thanks for reporting back chiEngr, that's gracious of you. Sorry I led you astray on the special application fasteners.