Substrate for garage floor slab

Good morning everyone,

in the next few days I would like to complete the garage floor slab.
As a base, I have clayey soil, with about 30-40 cm of compacted recycled material on top. Are 10 cm of well-compacted gravel sufficient here, and then about 20 cm of concrete on top?

Best regards

What type of garage is it? A prefabricated garage always comes with a foundation recommendation. We have a strip foundation on the two short sides, which goes 80 cm deep. (80 cm always because of frost risk) Maybe someone else who knows more will get in touch here!?! Regards Yvonne