Formwork stones - flowing concrete

Hello

I am going to construct a room from concrete formwork blocks. The floor slab is about to be created.
Now I will use concrete formwork blocks: 50x25x30. Reinforcement is clear. I would like to mix the flowing concrete myself. A concrete mixer is available.
Now the questions: What grain size of concrete gravel should I use? What is the mixing ratio (gravel to cement)? What additives are necessary to obtain flowing concrete? Is the concrete actually "self-compacting" or do I need to assist with a rod or a vibrating bottle?
I need 200 liters of concrete per m² of wall surface.

Steven

Funny, I'm currently dealing with that too or rather I ordered today because I'm using it to step down our light well.

But it's a bit different because it has to withstand earth pressure here - we used 0-32 grain size for that, since the foundation is also poured with it.

It's not pure gravel - but the mix ratio remains the classic 3:1 plus corresponding water (by feel). It’s still not self-compacting, so either a vibrating plate or a tamper, although the latter isn’t that great. But you pour/compact every 50 cm, so a tamper could also work.

0-32 I find quite coarse as a layman. For the concrete, we actually always used 0-16 gravel. With 3:1 or 4:1 you normally can't go wrong. Better to use a little less water at the beginning and add some more just before finishing. Best with a small bucket, then you quickly get a good feeling for the amount at which the concrete "flows".

Hello

I process about 600 block stones. So I really need proper ready-mixed concrete. Otherwise, I will tire myself out stamping.
Can I actually mix it myself in the mixer? Or do I have to have it delivered in the silo?

Steven

Yes, of course flow concrete - hardly earth-moist

But this is going to be quite a story for you - it seems to me that you are underestimating it a bit. That's well over 6 cubic meters you need there - doing it yourself will be cheaper but quite labor-intensive.

I would have the stuff delivered...



Well, it depends on what you want to do - sure it's coarse, but it holds accordingly. You don't mess around with earth pressure, so I'm playing it safe here.

That will be a lot of stuff. What are you planning to do with it? What kind of room is that supposed to be?