drilled and epoxy rebar into 3" concrete slab on NC metal Deck.

[torres_303]

Hi everyone. Hope someone can shine some light on a project I'm working on. Project is located in the USA, and I'm using the ACI 318-14 for reference.

I have a mezzanine designated for mechanical equipment. The mezzanine floor is existing, consist of a 3" concrete on top of NC metal deck. The slab has some floor openings for some old MEP equipment and those need to get filled and covered. There's 14k steel joist at 5 ft o.c. and my plan is to get some formwork (either same type of NC deck), and pouring concrete on top, with some embedded rebar which would be drilled and epoxied. My problem is that being 3" thick, I don't meet the requirements for the critical edge distance for the reinforcement (assuming I'm using a Hilti HY-Hit 200 adhesive). The ICC-ES ESR Report indicates that connection capacity can be reduced if the critical edge distance can't be met, and refences to ACI318-14 17.7.4. I've gone through the ACI chapter 17 and can't seem to find what the reduction factor would be for an adhesive connection. Can anyone give me their opinion for this type of scenario? I appreciate the info.

 

[JedClampett]

That calculation is a pain in the backside. It can be done, but I'd get the free version of Hilti Profis (don't pay for it and encourage them) and give it a spin. It's on their Website.

 

[torres_303]

free version of Hilti Profis

I've ran the calcs in there and I get issues with the edge distance between bar and edge of concrete. Can't seem to have a option to reduce capacity due to smaller critical edge distance.

 

[dold]

Is the existing opening framed with steel? Misc angles, etc? Or was the opening just kindof cut into the slab at some point?