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[Sosokrates]

So im laying some new paving slabs in my garden.
As the mortor im planning on using about 35% gravel and 65% of some kind of building sand as the aggregate in a 5:1 cement mix. Your meant to use just sharp sand but you can use a gravel and sand mix.
I made a test batch of concrete with the recycled materials and after 48hrs it has dried hard but if i scratch it with my thumbnail you can scratch of dust.
So my question is, how hard is a 5:1 concrete meant to dry after 48hrs? Is it meant to dry rock solid or will that take longer?

 

[Maiden Voyage]

So im laying some new paving slabs in my garden.
As the mortor im planning on using about 35% gravel and 65% of some kind of building sand as the aggregate in a 5:1 cement mix. Your meant to use just sharp sand but you can use a gravel and sand mix.
I made a test batch of concrete with the recycled materials and after 48hrs it has dried hard but if i scratch it with my thumbnail you can scratch of dust.
So my question is, how hard is a 5:1 concrete meant to dry after 48hrs? Is it meant to dry rock solid or will that take longer?

What does the package say for cure time? I think 78 hours to be safe.

 

[Sosokrates]

What does the package say for cure time? I think 78 hours to be safe.

It says something about 7 days curing on the technical data sheet, but i dont know if its what your talking about.

This is the product I have.

Multicem® cement in plastic bag

Multicem® cement in plastic bag

www.hanson-packedproducts.co.uk

 

[Maiden Voyage]

It says something about 7 days curing on the technical data sheet, but i dont know if its what your talking about.

This is the product I have.

Multicem® cement in plastic bag

Multicem® cement in plastic bag

www.hanson-packedproducts.co.uk

7 days it is then.

 

[Sosokrates]

7 days it is then.

It says this


"CONDITIONS OF USE
• Methods to prevent loss of moisture from exposed surfaces of concrete, known as curing, should
be employed for at least the first 7 days after casting"

So this is just a more complex way of saying "its got to be kept dry for 7 days?

 

[Maiden Voyage]

It says this


"CONDITIONS OF USE
• Methods to prevent loss of moisture from exposed surfaces of concrete, known as curing, should
be employed for at least the first 7 days after casting"

So this is just a more complex way of saying "its got to be kept dry for 7 days?

Yep. Curing in this case is the hardening process. 7 days is more than I’m used to but my limited experience is with quick curing mixes.

 

[Sosokrates]

Yep. Curing in this case is the hardening process. 7 days is more than I’m used to but my limited experience is with quick curing mixes.

Outside it will be even longer if it rains.
I will check my test after 7 days, but I will be surprised if it ends up grinding down my thumbnail instead of the other way round.

 

[Tschumi]

I'm not sure scratching off dust is an indicator of strength or curing, i think it's an indicator of your mix's water and cement content.. that might have implications for permeability though.. just do things by the book, imo, better a sure thing than concrete cancer

Edit: sorry i was walking around a crowd while i wrote this, it isn't totally relevant, my bad

 

[Maiden Voyage]

I'm not sure scratching off dust is an indicator of strength or curing, i think it's an indicator of your mix's water and cement content.. that might have implications for permeability though.. just do things by the book, imo, better a sure thing than concrete cancer

Edit: sorry i was walking around a crowd while i wrote this, it isn't totally relevant, my bad

Poetry in motion