Concrete gone off a bit quick

[Wigeon]

Laid some c40 with fibres on Tuesday onto existing concrete to bring the levels up. Only had 80mm to deal with, so not ideal.

Anyway, it went off seriously quickly -walking on it within 3hrs. Will it be OK, or is it likely to be knackered? It against a wall so won't have much traffic. Should I have put a membrane under it? Everyday is a school day round here...

Thanks

 

[br jones]

Give it some water

 

[Wigeon]

Thanks- even now 48hrs later?

 

[MrA.G.]

Thanks- even now 48hrs later?

Yes

 

[Hotbed]

My experience of someone giving concrete water, don’t do it with the sun on it. It will crack.

 

[Pan mixer]

Plastic under would have been a good plan

 

[multi power]

My experience of someone giving concrete water, don’t do it with the sun on it. It will crack.

It didn't get enough water

 

[John Chance]

Was the cement in the concrete pure cement (OPC / CEM 1) or was it a blend (slag and cement or ash and cement) ? C40 will go quick if its pure cement esp. when it's warm. Always spray water on.

Setting quick won't cause problems unless you tried to move it or compact it after it had started setting.

Edit: It is much more prone to cracking in first few days though.

 

[Northeastfarmer]

I hosepipe new concrete for 4 days after laying