ACI Slump Test: ASTM C143 Concrete Slump (Newer Version Available, Click Top Right Corner)

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Slump
ACI Technician Workbook CP-1 (13)

[sicerts]

Great question. I've heard contractors say a 5" slump is the "perfect" slump for workability but stiff enough to suit most applications. But there isn't really an ideal range. It just depends where it's going. For example, a parking garage ramp with a significant climb would most likely take a 4 to 6-inch slump. Any higher and the concrete slides down. A load transfer beam with heavily congested reinforcing steel needs high slump (8 to 10 inches) to fill in all the gaps.

[matthewgsteel]

Taking the test for the first time soon. Thanks for the help.

[PursuitOfParfection]

almost like an scc mix haha good video, I just got my level 1 aci/mca certification last week.

[NstSmt]

Depends on the specs for what the Engineer calls. Depends on the type of concrete, or any additives and where it's going.

[yahyatere]

A collapse slump will generally mean that the mix is too wet or that it is a high workability mix, for which slump test is not appropriate

[sicinfo]

Hey Rakib, we have an updated video on this FYI. But to answer your Q, there's not really a standard diameter, or we don't think of it that way. The cone dimensions are standard, which makes the diameter of the material inside consistent. What varies is the height of the fall or slump of concrete, and that's what we measure to record the slump.

[sicerts]

@JSSTyger - Magic. Actually, he had his left hand still on the handle and held the entire cone down. Not always so easy but he renewed his gym membership.

[sicerts]

@Wray - Can you share 2 and cite references from C143?

[makesumwake]

measuring it when its that wet is pointless.  its obviously too wet by just looking at it in the scoop.

[JSSTyger]

What the hell was holding that slump cone down at 2:41 when he decided to take both feet off and one hand?

[nidilian]

this should of been tested om a flow plate

[colonelmusket]

Collapse slump, i.e.,  not a true slump.  As well, the concrete partially flowed off the board.  I don't understand, unless you were doing this purposely to incite discussion, why would you use such a "wet" mix with coarse aggregate to demonstrate the slump test in the first place? 

[serenaucsc]

That's a significant amount of slump.

[winston]

Not a slump, but a slosh.
Either it is way too wet, or somebody got enthusiastic with the HRWR.