What is mix for no fines concrete - Ned help with nix

[Rick]

Want to mix up some no fines concrete ... anybody know correct mix, I have done a bit of Googling around and found
6:1 8:1 and 10:1

I have put in a struts to support shuttering, these are fixed to an 'on edge' timber. (As per drawings on this site)

I had to cut a slit trench for the timbers (struts run at 60 degree to top waler of shuttering)
I want to back-fill behind the timber to provide full support when concrete raft is poured.

I can leave the concrete in place afterwards as it is well below ground level.

Rick

[Tony McC]

No fines concrete is specified by the quantity of cement per cubic metre. Anything from 200-300kg/m³ would be 'normal', depending on what use you have for it.