Urgent - Concrete pouring for support slab: volumne or weight ?

[Lucag]

Sounds reasonable, thank you very much! Will keep an eye for the consistency!

[fox]

You still should work out your proportions of sand to aggregate. For my money 6:1 is not strong enough for this application. Here is a guide for various concrete mixes.

http://structx.com/Material_Properties_011.html

Ha Ha very interesting, I have just built a three story house useing over 50 tons of 6-1 concrete ... I hope it is strong enough!
Of course I don’t really have much choice as building regulations define the mix.

[Lucag]

Tomorrow I’ll pour the slab finally! I have decided to go for 6:1 ballast/concrete and decide with my eye how much water to add. If you guy have any comment on how to put the net or the support i’ll Be glad to hear that. I really hope that everything will turn out fine

The wood on the inside will remain there, blended with the concrete. The external wood will be removed.

[fox]

Do you have a way to vibrate the wet concrete, if you can find a way, it will produce a much stronger end result.
Hiring a concrete poker would be one option if it is not too expensive, a wooden dowel in a hammer drill works to a degree as a virbrating sander does but a poker is by far the best way.

[david s]

Presumably the stool legs are to provide some drain holes in the supporting slab? If so, unless the legs are all perfectly vertical and well oiled, you will have extreme difficulty removing the stool. Casting around things like that, it is better to wrap plastic around it for easier removal. Or you could just cut each leg off flush with the top of the slab, leaving behind the embedded bits in the concrete, this could be handy if you want a nice low stool for a child , In either case you'll also need to drill through the ply under them if the holes are designed as drainage.

[Lucag]

Eheh the stool was there for when I covered the oven to protect it from the rain. Thank to the stool supporting the plastic sheet no rain stagnated inside the structure itself. The stool will be removed before the pouring


I did not know I had to make drain hole in the wood!

The internal wood: I will leave it bonded with the slab.

External Perimeter wood: I have a concrete release agent and I will brush it on the wood. It’s water repellent and this will allow me to detach the wood properly I think.

do you suggest me to create drain hole ? Where, and what for?

thank you