Powder Actuated Fasteners

[stevenspm]

Has anyone heard of using p.a.f.'s in the top of a cont bond beam to attach something like a light gauge track as opposed to using an anchor bolt or an expansion anchor.
Thank you.

 

[CANPRO]

Yes. Hilti has a fastener called the X-U Universal Knurled Shank Fastener. They list allowable loads in concrete, steel, hollow/grouted CMU and in the top side of grouted cells.

 

[jayrod12]

as long as the PAFs provide documentation for what loads you have to resist, i.e. pull-out and shear, I don't see why you couldn't use them. The dilemma comes because PAFs could very easily punch right through your light gauge track or not embed enough into the concrete.

 

[XR250]

It is done all the time. They don't work very well for uplift in this case (if you have any)
If you do, you are better off with an anchor bolt and a Stiffclip CL (from the Steel Network) as needed.

 

[civeng80]

IMHO PAF dont work well and are very dangerous.
Had some bad experiences with this in the past and will not touch them again.

 

[Jerehmy]

I've used them but aren't particularly fond of them. They seem pretty weak for something punched into concrete. Used Hilti for a bottom track of CFS wall.

 

[XR250]

They are used in 100% of any construction that has light gage steel. The design values in concrete and masonry are pretty low to account for spalling etc.

 

[stevenspm]

Thanks for the information, I have used them before but mainly for attaching interior partition walls to a slab or occasionally exterior curtain walls. Being able to use them at bond beams solves some problems that using ancgor bolts would cause.

 

[CANPRO]

civeng80, can you expand on your bad experience? I specify these fasteners for light gauge all the time, I haven't run into problems yet. If there is something I should be watching out for I would appreciate the insight.

Thanks.

 

[civeng80]

I had a contractor using PAF attaching timber on a steel column (vertical), there were glazing contractors not far away and the pins were going through the steel and timber and the ends were breaking off and shooting out behind the steel like bullets. I was lucky no one got killed. Bizzare, but dangerous.
I for one will never touch or specify them again.

 

[XR250]

If you are designing light gage and "don't" specify them, expect to be out of a job

 

[Ingenuity]

civeng80,

Seems like the PAF in your situation were used with incorrect powder charge type and the contractor did NOT do a test before proceeding with production fastening.

 

[civeng80]

The steel was not light gauge steel, it was hot rolled and about 8mm thick.
It was a licenced and Ramset recommended sub contractor doing the job.

No one realised the pins were breaking and shooting out, because most of the pin was doing the job.

Bullet holes were appearing in the glazing in front of the building and police were called because we thought someone was doing drive by shooting or something like that.

Then my father (a retired builder) and I went there on the quiet Saturday morning, and worked out was was going on. Found part of the pin about 1/4" in the rubble near the bullet hole in the window.

PAF not for me under any circumstances.

 

[XR250]

Maybe it was a bad batch of pins. Stick with Hilti next time :>

 

[TDIengineer]

Shot pins are used extensively for interior metal stud construction of light gauge framing in my region. Typically used at a composite type floor. Shot pins are in shear only, for the top and bottom track connection. Any suspended light gauge soffits are hung with wedge anchors not shot pins.

The ICC reports I deal with exclude seismic and wind loading from the "scope of the report". With that said, I limit it to non-structural interior items only and in shear only.

And yes, if you didn't specify them for this type of construction, and showed all wedge anchors, you would look very silly.

 

[XR250]

@TDIEngineer - you would look silly if you did not specify them for exterior wall construction as well.

 

[TDIengineer]

@ Excel-
In California that doesn't meet code actually. The exterior wall will be subject to wind and seismic. The ICC-ESS reports for powder actuated fasteners are beyond the scope of the report.
So if you're getting away with it, it is due to lack of enforcement. For California hospitals this would get your project stopped. And this is because healthcare construction enforces every part of the code you can think of.

 

[TDIengineer]

I didn't say that very well. See attached for the exception. This possibly does not apply to your region.

 

[XR250]

@TDIEngineer
Makes sense in CA. In NC, seismic load is minimal on curtain walls.