Concrete crumbling in between paving

[utterlydiy]

Approx a month ago I did some filling of the gaps of my paving and found today to be crumbly.

The gaps were cleaned of soil etc and brushed free of dust etc. and to the the depth of the slabs of 50mm.

The mix was 5:1 and wet enough to hardly squeeze any water from a fistfull. The mix was compacted down in the gaps and spooned the surface to the desired shape and water could be seen to glisten on the surface.

Only a bucket at a time was made to do an area at a time.

Any clues why the crunble.

thanks

 

[SittingBull]

Was the cement in date - did you mix 100% perfectly well?

 

[utterlydiy]

To be honest, it was out of date by a few months. But it was still as dusty as you would expect as I kept it in an air tight container.

Didn't realise date was a factor.

So from what you are saying, I'll have to remove the crumbly concrete and use a new mix with fresh cement with a 'use before' valid date.

Thanks

 

[SittingBull]

Ah, I'm speaking from past personal bad experience. It's frustrating doing things twice! Perhaps make your mix just slightly wetter next time as well to prevent it drying too quickly. Good luck!