Bricks, Masonry, Asphalt and Concrete - concrete question

Hi all, I have a concrete floor that needs about 10' by 2' of it that needs to be broken up inorder to run some plumbing lines. The finished floor of choice will be tile. How I am to fill the hole with concrete inorder to prevent vertical or horizontal movement of the new slab adjacent to the old without cracking the tile. The concrete slabs need to be joined well. The plan right know was to drill holes 6" deep at a 3/4" diameter in the concrete slab at angles spaced about every 10" on the thing long ways and 8" the short 2' way, then insert 1/2" rebar in them. Ill have to epoxy in the rebar or something of course. Next I was going to pack the dirt below with a very good ram rod and then fill with concrete mixed with alittle more additional strength (1 cement, 2 gravel, 1 washed sand) What do you gyes think about this. Thanks alot for helping. :)

I have a similar situation and I'm doing the same thing except for using 1/2" rebar. There really is no horizontal movement just the potential for vertical drop, but the rebar should stop that.

Another issue is the new concrete cure time (30 days min.) before tiling and cracking under your tiles down the road. The best way to prevent that is with an uncoupling membrane like schluter ditra.

Good luck! :thumbup:

Are you using 3/8" rebar, did you set them in with epoxy, thinset etc.. What spacing is yours from one rebar to the next. I am sorry for have so many question. Don't want it to fail ya know ;)