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How does CLEVA-crete change concretes behaviour?

CLEVA-Crete provides concrete with a greater quantity of C-S-H gel. Instead of the type of gel that is created from fly ash or silicon fume, this gel ‘sets up’ the concrete slightly higher but slumps well as while the concrete is in its plastic stage it enables the aggregate to rollover much easier.

This simple difference means that you immediately have plenty of working cream when you start screeding and using edging tools. There is little to no bleed water, so bull floating is made easier and the surface gets very flat, you can get on to finish it earlier with helicopters and final finishing techniques.

Does the MPa take a hit? Do you get earlier strength or is there a delayed setting time?

It starts curing from the inside out, not the outside in, so instead of waiting for a couple of hours CLEVA-Crete will decrease the set times by about 13 to 17%, allowing finishing work to start about an hour earlier. You should find that working with walk behind or ride-on helicopters, the concrete will get a lot flatter quicker than normal and you can be finishing up usually 1 to 2 hours earlier than normal.

In winter, where normally with most other technologies the slowdown of setting times are delaying finishing by hours, this will keep things on time and generally early if there hasn’t been too much H²O added in.

When CLEVA-Crete is in the matrix, does it make the concrete go off faster?

The concrete will set 13 to 17% quicker. There isn’t any need to be concerned about this, a shorter morning tea is all it usually takes. CLEVA-Crete just decreases the set time rather than increases it like crystal growth technologies do.

Are there certain projects or situations where CLEVA-Crete shouldn’t be used?

In a word-no. It gives a superior finish. It lessens the usual shrinkage. It lowers the heat of hydration. It reduces DEF and ASR and stops slab curl and surface dust. Then, over the structure’s life cycle, it also stops or reduces carbonation, chloride and sulphide ingress from destroying the concrete.

How does it compete or behave with similar waterproofing options?

CLEVA-Crete creates a beneficial gel for the concrete without turning into pots of jelly that take their time to go off. Compared to crystal growth options, finishing will occur 1 to 2 hours earlier as opposed to 2 to 4 hours later.

When compared to Caltite, it is different in the sense that it is not a hydrocarbon, is not toxic or carcinogenic and has no smell or odour that you might find offensive to work with.

What cost is it to buy per cube?

CLEVA-Crete deals directly with the major concrete ready-mix providers. On site and with large crews, there is room for margins of error and CLEVA-Crete must be dosed accurately through computerised batch plants or certified trained dosing operators.

Please call your concrete supplier today.

Does the slump stay the same when the concrete has CLEVA-Crete in it?

The slump is different from mix design to mix design, but it will generally increase the slump. The gel created causes the stone to roll over very easily when the concrete is in its plastic stage and because it is dynamic, it causes the mortar around the stone to be more even. It is also one of the reasons why the concrete is 4 to 11% stronger after 28 and 56 days.

Please be aware that when the concrete truck rolls up to the pump and the concrete slump appears low, it likely does not require as much water as you might ordinarily add. The slump is likely right where you want it, so be careful not to overwater.

What changes in finishing techniques will be evident when CLEVA-Crete is in the mix design?

As it cures from the inside out it is easy to get used to the change very quickly. On large slabs finishing can happen around an hour earlier than normal due to setting 13 to 17% faster. When you do get to finish off, you will seldom need any water to do so, even though there will be little to no bleed water.

There will be no need to work up a finishing cream and you will get the concrete very flat, in less time than normal. You can get a nice hard burnished finish on the concrete just the same and in many cases, on large slabs you can cut the control joints in on the same day as the pour.

Can you still get a nice burnt finish when CLEVA-Crete is in the concrete?

Yes you can. The reason end users often want a hard burnished finish is so that the concrete turns out a lot denser. CLEVA-Crete is a great densifier for concrete, more than many on the market.

The nano sized particles of calcium silicate hydrate that are produced fill any void in the concrete’s matrix with a resultant dense hard finish that you would ordinarily try to achieve by burnishing the top.

How old is the technology, and when was it first used in Australia?

The technology itself is thousands of years old. It was re-visited 100 years ago for the Hoover Dam project by the American Army Corps of Engineers. They used it in a powder form which worked very well for them, however with modern batch plants we have found that this technology in a dry powder form competes for the water at the batching process, so CLEVA-Crete was formulated in a liquid. This can go in with the head water or it can go in last just prior to being utilised on site.

This technology has been used in Australia for over eight years now, on projects including large scale warehouses, aquariums, hospitals, aged care facilities, levee banks, many schools and day care facilities and high-end residential buildings.

Why should we request the use of CLEVA-Crete on our products?

CLEVA-Crete is cheaper to buy than anything else, it pumps easier than anything else and drops the pressure in the lines by 35% on average, is just as easy to spread, makes the bull floating process easier, doesn’t produce any annoying bleed water and enables you to finish off 1 to 2 hours earlier saving time and money over and over again.

Does CLEVA-Crete help with delayed setting times?

Yes it does. When poured in limestone it can decrease the set times by up to 17%. It’s good to note that if customers request a rumbled top finish, which takes time to create and manoeuvre, you will find that if you get onto it straight away you will still have plenty of time to get great looking finishes.

If it is a concern to you, some have found that by using a very small amount of Super P in the mix, this gives them an extra hour or so to play with textures and desired results.

Do you have any further questions? If so, please contact us at info@clevacrete.com.au.

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