Headed Stud Mislocated

[slickdeals]

Folks,
I have a situation where a contractor mislocated a cast-in embed plate with 1/2" dia studs x 4" long on a grade beam. This embed transfers wind shears at the foundation.

The contractor wants to drill a hole 1/16" larger than the stud head (1/2" bigger than the shank), fill it with epoxy and hammer the plate in at the correct location. I am concerned whether this detail even works because of exceeding epoxy adhesive specifications for hole diameters.

A crazy option I was thinking is if you cut off the heads of the stud, creating a smooth dowel. And then insert the plate as a post-installed plate, into pre-drilled holes filled with epoxy.

I have never used smooth dowels for epoxied rods, but was curious if others have any ideas/opinions.

 

[TXStructural]

You need to design a proper post-installed anchorage. It is doubtful that 1/16 oversized hole will be sufficient to allow setting the plate, and doing so with smooth dowels won't really do what you are trying to do.

Some adhesives allow oversized holes, with proper anchors.

Look at the proposed ACI 318-11 Appendix D for adhesive anchor design.

 

[MiketheEngineer]

Check out Simpson, Hilti, USP, they all have epoxied dowels with some pretty good values. Just abandon what is there and start over??!!

 

[slickdeals]

The problem is that it receives a precast wall and hence, I am trying to see if I can help the contractor....... IT needs to be flush mounted

Post-installed connections will stick up and have a nut. This would somehow interfere with the precast panel.

 

[TXStructural]

You can carve out some of the cover on the concrete, and can recess the nuts as needed using two steel plates laminated together with holes large enough for the nuts in the outer plate.

How far from the correct location is it?

 

[azcats]

How about installing proper adhesive anchors and then using a plate with holes to match the anchor pattern. Leave the anchors below the top of the plate enough to provide weld b/w the top of the anchor and inside of the hole.

 

[hokie66]

Countersunk bolts could be used for the anchors.

 

[Zambo]

What about just breaking out the beam as required to fit the original plate and then grouting the area. It might seem like a big job but you could start straight away with the breaking out and in the meantime select a good non-shrink grout and approve grouting method. It'll be finished by Friday.

 

[port125]

Some epoxy has good values for rebar, so I propose getting some weldale rebar (A706?) and welding it to the back of a new plate. this can then be set wherever you want in new or old holes. this way there is nothing counter sunk and you are still flush.

 

[a2mfk]

I like port's idea and have used it with weldable rebar. I'm working on an embed connection with a LOT of tension right now and am going to use a similar detail, only cast in place. The contractor just has to make sure he gets the holes drilled exactly right so all the rebar align with the drilled holes, I'd use a template myself.