Posted By ICFconstruction on 04 Jul 2012 10:57 AM
Dowels are good. Key-way footings are better as there is the added benefit of a harder path for water to follow. But without either, you can remove 6" of eps 2' oc to allow the concrete floor to flow to the concrete of the ICF. This was an option a MN engineer had in their packet for all users of NUDURA locally. Easy fix, not a big deal at all.

If backfill on both sides we only put dowels 6' oc.

Good point, STATICCLOVER you should probably do this when you run the rebar on your fix. Remove the interior EPS in those areas so that the slab concrete can go against the concrete in the wall, along with the rebar attachments.

This 'just' happened. Have you already paid them in full?

I drilled the holes for 60' of the wall tonight and it hasn't been bad at all, it was more work to get the excess concrete off of the footer than the drilling. The engineer backed off on the number and size of the dowels Monday after visiting the site. We're using 1/2" rebar now and we're starting one foot from the corner with one in the wall and footer and then alternating one in the wall and then one in the footer every 2'. So that puts us 4' on center for the wall and 4' on center for the footer.
The engineer said the work looked good when he visited, except for leaving out the dowels of course, but the need for them appears to be reasonably debatable. I know that I will feel alot better about the house now that they we have accounted for them. He was not concerned at all about the vibration method and so far I found solid concrete in the spots I have removed the foam to put the dowels in. I'm still debating on rather or not to remove the 6" strips of foam every 2', would that have much affect on my slab insulation or would it be worth the extra concrete contact?

I went back and looked at the engineering I was referring to. It says use #4 dowels every 2' OR dowels every 6' and remove 6" of eps every 2'.

Your engineers fix is good. I don't see why you would have to epoxy the vertical rebar. I would remove the foam 3" each side of the horizontal dowel and skip the epoxy there too, but the dowel could also be skipped.

The epoxy would be if you have insulation between the two concrete pieces you are joining with the rebar.

Your slab will have a lot more contact with the footing than the wall concrete. Are you planning on having insulation between the slab and footing, or the thickened edge as shown on the engineer's drawing?

I don't see why you would have to epoxy the vertical rebar.

What is that based on, Brad?

An alternative to the epoxy for setting the rebar dowels is non-shrink precision grout. When mixed to a fluid consistency it still has a compressive strength of ~8000 psi. Mix some up to fluid consistency, put it in a grout bag (similar to a cake decorators bag but heavier duty), and pump the holes full before driving the rebar in.

I used the Quikcrete listed below to relocate some dowels in my ICF footings.  It worked great and was far less expensive than epoxy.

http://www.quikrete.com/productlines/NonShrinkPrecisionGrout.asp

http://www.lowes.com/ProductDisplay?partNumber=209-286-158500&langId=-1&storeId=10151&productId=3024210&catalogId=10051&cmRelshp=rel&rel=nofollow&cId=PDIO1

http://www.wrmeadows.com/588-10k-mi...ion-grout/

Posted By staticclover on 22 Jun 2012 03:59 AM
... Also when we started pouring the walls, no concrete vibrators were used, they used a rubber attachment on cordless impacts on the outside of the walls...

Did the "rubber attachment" you mentioned above look like the vibrator shown in the link below?  If so, that is the "Wallbrator".  I have one and used it on my ICF basement and ICF main floor.  It does a good job of consolidating the concrete.  You can watch the concrete flow under windows and at the top of the wall when this is used properly. 

I have many interior and exterior anchor bolts set in my walls at varying heights.  I cut 2" round holes in the foam and attached the anchor bolts to scabs of OSB that was then screwed to the ICF ties prior to the pour.  After the pour and after the OSB was removed, the concrete had flowed through the 2" hole in the 2-1/2" of foam and was flush with the OSB on the outside of the foam.  This indicates to me that the Wallbrator does a pretty good job of consolidating the concrete.  And many of these anchor bolts are on the outside of the wall and all vibrating was done on the inside of the wall at the tie locations.

http://www.youtube.com/watch?v=J6DAFaG5ABU

Yes, I believe it was the Wallbrator.

You guys realize that it's a BIG no no to use a vibrator to "move" concrete under windows, into corners or anywhere else, right? You're supposed to place it where you want it and vibrate it to consolidate.

I wasn't implying that we intentionally moved or placed the concrete under the window sill with the vibrator, just that it was easy to see it move there, like at the top of the wall. The concrete at the top of the wall and under the window sills would drop an inch or more when we applied the vibrator.

Posted By ICFHybrid on 05 Jul 2012 08:39 AM

I don't see why you would have to epoxy the vertical rebar.

What is that based on, Brad?

I mean if the dowels are just for shear, why would they need epoxy. Just like if dowels are not wet-set, and drilled into the footing.

It's amazing to see how much the concrete drops down after it is vibrated. I've seen videos where it sank another 6-12" after being vibrated.

Did you peel the ICF to install dowels?
If then Your slab is touching to the walls without expansion pads.
It also on the footings.
This design does not look like perfect.
???

I've seen videos where it sank another 6-12" after being vibrated.

If it drops that much, then whoever placed it wasn't watching closely enough.

If then Your slab is touching to the walls without expansion pads.

What is going to make it expand?

I tried to upload a picture of the fix, but I couldn't get it to work. Installing the dowels wasn't too bad, but the turn downs soaked up a good bit of concrete when we poured the slab. Thanks for everyone's help.

Posted By staticclover on 06 Aug 2012 11:59 AM
I tried to upload a picture of the fix, but I couldn't get it to work. Installing the dowels wasn't too bad, but the turn downs soaked up a good bit of concrete when we poured the slab. Thanks for everyone's help.

If you don't mind me asking, what did it cost you to do this fix??

Lbear it's kinda hard to say,for the rebar and epoxy and drill bit around $250. If you want to include the drill add another $300, but I'm going to need it for several other things on this project and I really couldn't say for sure on extra concrete but I'd say it took at least 3-5 extra yards. Labor was all on me. I'm just really glad to have it all sorted out and moving on to the rest of the project.