We're located in a seismic area where PT decks are to be considered cracked concrete for the purpose of hanging and bracing. We see a lot of the Dewalt Mini Undercuts and now the newer Hilti HDP-TZ inserts being used to hang up to 4" pipe from the concrete decks. The data sheets show them with pullouts of under 240lbs.
How can these be used to hang ANY sprinkler pipe if the minimum required capacity of the hanger assembly is the weight of the water filled pipe plus 250lbs?
Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe
5/13/2019 10:33:24 am
Hey ! How are you ?
5/13/2019 02:50:17 pm
You are correct. You can't use them. For the hangers, there's a Sammy swivel SH-CCST-516, which is a concrete screw 5/16-14 x 2 1/2"... 857lb pullout for cracked concrete and seismic zones A-F, but it's not FM approved. They're expensive, but they save on labor b/c no pre-drilling.
5/13/2019 02:52:09 pm
Correction- the sammys require a pilot hole, but still easier than setting an anchor. Sorry, it's been a while since I used them.
5/14/2019 03:12:05 am
Drilling in PT slabs is not a good idea. The tendons could be cut and many time the structural engineer will not allow it.
5/14/2019 03:16:30 am
Sammy CST 20 for 3/8" rod is FM approved at 1,475#
Leave a Reply.
Subscribe and learn something new each day:
Top April 2023 Contributors
Get 100 Days of Free Sample Questions right to you!
PE PREP SERIES