[davischevy]

Originally Posted by 1976gmc20

The way we used to do it was with pieces of angle iron, about 1" or 1.5" ? There were holes drilled at intervals right in the corner of the angle iron. So after setting up the 2x6 forms, we would nail these angle irons to the forms with the two edges against the wood. After the slab was poured and the forms came off, a V-shaped groove was left in the edge of the slab, which was of course a mortise for the concrete that would be poured next to it.

When doing a truck apron for a major chemical outfit, you can't begin to pour it all at once. We poured in strips about 20' wide and a few hundred feet long, since our vibrating screed allowed that width. And we formed and poured every other strip so the ones in between could be poured without forming.

It was a horrible job and I never want to do that kind of work again, but that is how we did it if it helps any ...

We have nailed a V shaped piece of wood on the inside of the form to create that notch.