What is your base for concrete and your reasons?
Figured I had some questions to ask and see what others had thought about them.
I'm in St. Louis area. So, lots of freeze thaw cycles.
Dig in 6in usually, depending on sight and put in 4in of 3/4 clean gravel.
Depending on location, will also put a pipe in the low area of the gravel, so any water under pad comes out of pad and doesn't build there.
Never use sand, it hold water.
We have a lot of clay and it will heave.
Never pour on dirt.
Our pads are basically floating pads. Floating on the gravel. Walkways the same.