pumped concrete

[Phil L]

Laid 3 cubic metres of this yesterday, pumped from a wagon 40m away, it was like piss. It found it's own level easy enough but I wasn't happy about the water content. It came through a 150mm diameter rubber hose with steel connectors, when they've finished (it took less than 15 mins to pump 3 cubes) they send a hard foam ball through which cleans out the insides of the pipe - it comes out like a bullet and makes one hell of a bang. We had to get it pumped due to width restrictions - we couldn't get a barrow through, but that said, I don't think I'll get it pumped again, the consistency was all wrong and when tamped, about half a cube of water was removed, this isn't good as it tends to leave the aggregate at the bottom, the cement paste in the middle and sandy watery s**te at the top

[dennis]

That sounds like operator error as they don't need it to be wet to pump. A decent pump will do an almost dry mix. Did you have a slump test done?

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[Rick Hughes]

I have used pumped several times ... it should not be too wet .. as this as you found will separate.

Did you specify that he mix was for pumping ? ... as there are specific pumped mixes.

A slump test would have quickly identified if it was too wet.