Concrete work after backfill

[Huskerfan-23]

I cut my basement slab (4 inch slab) open and roughed in a new bathroom (toilet, lav, and shower) and also basement bar. I tied into the existing PVC under slab for all work. I filled under all of the new lines with pea gravel up to the springline of the pipe and then backfilled from there with native soil that was taken out.

I am now ready to do the concrete work, but wanted to get everyone's input on if they typically dowel rebar into the old concrete before pouring the new? Keep in mind this is a basement so the temperature fluctuations wont be much and it seems like doing this could be overkill. That said, I definitely don't want to have to deal with brittle concrete in the future and have to tear a bathroom apart because I skimped.

Let me know how you guys typically do it!

 

[Breplum]

We only use road base backfill under pipe because simple pea gravel is unstable. Road base has fines and compacts tightly, preventing subsidence over time.
We always dowel some rebar pieces into each side of the slab cut, then ideally, bridge the dowels with a jumper piece of rebar. Epoxy not typically used for the doweling.

 

[Sponsor]

 

[Huskerfan-23]

I was going to originally use 3/4 crusher base under the pipe (which is PVC) but read others on this forum saying it was a risk because they had seen the crusher rock "poke holes" in the PVC pipe once the weight of the backfill was put on it so I went with pea gravel.

I am glad to hear you dont use epoxy... that stuff has really gone up in price!