Set formwork blocks on the foundation or in concrete

Hello everyone,

a pit is currently being dug for a pool. The pool will be built with 17.5 cm formwork blocks. One long and one short side of the pool are up to the top edge in the ground, the other two walls protrude about 2/3 out of the ground.

I will not completely pour a base slab but will pour it later into the pool once the walls are standing.

Do I now have to make a foundation with reinforcement and connection reinforcement for the outer walls on my gravel bed and then set the stones there, or would it be sufficient if I set the first row of the formwork blocks on the gravel bed in concrete and then equip the stones accordingly with reinforcement?

Is there a structural difference whether with or without a foundation in this case? It should hold from the pressure I suppose, but what is the difference whether I have a foundation and build on it or if I set the first row of stones directly in concrete?

Thanks for your answers

well.... pool construction do it yourself.... how big will the pool be? 6 * 6 meters? then there is considerable pressure on the walls

We also have a pool. A concrete slab was poured for us, just like for our house. I am an amateur, but how are the exterior walls supposed to withstand the earth and water pressure if you just place them on gravel? I wouldn't just start building like that, otherwise all the work will have been for nothing later. Can't you get information from a pool builder?

Best regards
Sabine

The pool will be 9x4 meters.

Filled with water from the inside and pressure from the soil on the outside... I thought more about the walls not being able to shift anywhere in the lower area.

Filled with water from the inside and pressured from the outside by the soil... I thought more that the walls can't slip anywhere at the bottom.

That's true! You only have the problem that a lot of time passes until your pool is finished. Until then, it presses diligently from the outside, especially if the walls are just loosely standing on the ground.

but where does it make a difference whether the walls simply stand on the gravel bed and are edged with concrete on the sides or whether they stand on a concrete base? I don't quite understand that

Shouldn't the version without a concrete foundation actually stand more securely?