Concrete countertops: Using superplasticizer to increase workability without decreasing strength

This quick demo shows how superplasticizer makes a high quality, low water to cement ratio concrete countertop mix workable, without adding any water. A low water to cement ratio such as 0.35 is essential for the high strength concrete required for concrete countertops. Superplasticizers are simply high range water reducers that allow you increase workability without sacrificing strength. In this video, we use BASF's Melflux 2651 at a 0.38% dosage.

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• concrete countertop
• concrete
• countertop
• mix design
• superplasticizer
• water reducer
• high range water reducer
• concrete countertop videos
• concrete counter top videos
• concrete counter videos
• cement countertop videos
• cement counter top videos
• cement counter videos

[kris0390]

I'm thinking about utilizing a material as partial replacement for superplasticizer.. what would it be.. it's for my thesis any idea???

[ConcreteCtopInst]

There is no substitute for superplasticizer. Superp is a very high range water reducer. There are low range water reducers, but they simply don't have the needed strength. You can purchase superplasticizer from Fishstone Concrete Countertop Supply.

[ConcreteCtopInst]

Superplasticizers, like all admixtures, are dosed based on the weight of dry cementitious material in the concrete. A 0.5% dose, for instance, means 1/2 lb of superplasticizer is added to a concrete mix that has 100 lbs of cementitious (cement plus any pozzolans) in it.

[UrbanSculpture]

You know, I had a thought after watching this again, on a small batch, if one had a vacuum chamber, you could mix as you did, put the container under vacuum and pull all the air out, this method is used for mold rubbers and pourable casting plastics too

[UrbanSculpture]

Seems it can also be used in hydrocal, or at least a similar product can be used in it it seems, thatmight be nice to reduce water in that and increase strength.

[UrbanSculpture]

I spent most of the time since I first posted, trying to locate a distributor or even a place to BUY this stuff. Ya get on the BASF site and it goes round and round, it's geared more for heavy industrial and is not user friendly at all.

I found all kinds of product literature but no where to BUY, then I finally found the sample order form page but still no link to a "buy now" store, so I'll await a sample in the mail I guess from that form I sent in.

[UrbanSculpture]

I do use concrete in my sculptures, 1 pt Portland, 2 pts fine quartz sand and keep it fairly stiff. I work it in the molds by hand and get of the bubbles out of the details, but it's still a pain. Makign it more flowable would enable a lot more trapped air to leave as it does using this technique with hydrocal.

I'll have to look into this.

[UrbanSculpture]

Hmm, this is interesting, first time Ive seen a video of this being used, the effect is quite dramatic and not unlike the same effect observed with adding a defloculent such as sodium silicate (water glass) to water clay to make pourable slip, without adding water.

[btbarbobot]

How do you calculate the superplasticizer amount? By weight?