Basement plumbing

[rocklobster]

I have moved some roughed in drainage pipes in my basement and now have a large hole in the cement floor. What is the best materials to use to fill in this hole so that it adheres to the existing cement and doesn't crack, and so that it is nice and flat and moisture resistant?

 

[Markts30]

Use some concrete bonding agent (painted onto the old surface - is milky white) and then regular concrete...
If you are worried about cracking/settling/heaving, you can "pin" the seams with rebar - you will need a roto-hammer to do this...

Seal the surface after a few weeks for the moisture resistance (have to let the concrete cure for a bit first....)