Modified concrete reduces need for cement

Savita Dixit, Professor, Department of Chemistry, Maulana Azad National Institute of Technology, and Gajendra Dixit, Professor Mechanical Engineering Department, were granted a patent by the Government of India for the new discovery of “modified concrete structure”.

This is the sixth patent of Dixit, before that she had been granted five other patents for her discoveries. In this new discovery, she prepared a concrete structure with the help of silica, fibers, GGBs, fumes, etc. which can be seen as an alternative to the presently used cement concrete.

Both Savita Dixit and Gajendra Dixit have been working jointly for the past 20 years through their discoveries to re-use, unusable waste items so that our environment can be made sustainable. Therefore, for this research work, she choose silica, fiber, GGBs, fumes, etc. because this type of waste is the most emitted by humans in the modern world, which is causing a lot of damage to our environment and natural resources.

This will reduce our dependence on cement by about 30 percent. The test also shows that the quality and strength of these concrete bricks made of silica, fiber, GGBs, fumes, etc. is higher than the concrete bricks made of cement and their cost of manufacturing is also less.

https://www.dailypioneer.com/2022/state-editions/manit-profe…

Jaak

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GGBS

Ground-granulated blast-furnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder. Ground-granulated blast furnace slag is highly cementitious and high in calcium silicate hydrates (CSH) which is a strength enhancing compound which improves the strength, durability and appearance of the concrete.

https://en.wikipedia.org/wiki/Ground_granulated_blast-furnac…

The Captain
learned something new today. Thanks.

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If only we could rediscover how the Roman made their cement.
https://science.howstuffworks.com/why-ancient-roman-concrete…

Why are millennia-old ancient Roman piers still standing strong as veritable concrete islands, while modern concrete structures built only decades ago crumble from an onslaught of wind and waves?

Researchers at the University of Utah discovered that as seawater filters through piers and breakwaters made of age-old Roman concrete, the structures actually become increasingly stronger because of the growth of interlocking minerals — including some minerals that are rare or expensive to cultivate in lab settings.

So why aren’t we using Roman-style concrete? For one, we don’t know the recipe. We may think we’re at the height of human knowledge, but the ancients did possess precious knowledge that has been lost to time.

There’s also a load-bearing issue. “Ancient” is the key word in these Roman structures, which took a long, long time to develop their strength from seawater. Young cement built using a Roman recipe would probably not have the compressive strength to handle modern use — at least not initially.

Modern concrete takes 21 days to reach full strength. It gains half strength in 3-4 days. At least that is what I remember as my days of a concrete tester.

Why are millennia-old ancient Roman piers still standing strong as veritable concrete islands, while modern concrete structures built only decades ago crumble from an onslaught of wind and waves?

Maybe Roman concrete didn’t have steel rebars that rust and swell…

How come buildings from the Roman Empire needed no steel reinforcement, when modern buildings do?

The correct answer is, I believe, that Romans never used concrete in tension, only in compression.

https://www.quora.com/How-come-buildings-from-the-Roman-Empi…

The Captain

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They do tell us that ancient Roman structures were damaged by scavengers for their iron content. The church declared many of them holy shrines in an effort to preserve them.

They do tell us that ancient Roman structures were damaged by scavengers for their iron content. The church declared many of them holy shrines in an effort to preserve them.

================================================================

What parts of the structures used iron? Any links to your statement?

Jaak

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Thats from a tour of Rome years ago. No links. They do have crosses on some of the structures.

It looks like you’ve done your research! This is a fascinating industry to me. I’ve been following it for a few years and I’m amazed at all the products out there. Definitely at a precipice of technology replacing legacy materials.

Are you familiar with SCMs (supplementary cementitious materials)–

They reduce the need for cement by 40% and in-turn reduce carbon emissions of cement manufacturing by 40%-- a huge opportunity in the carbon-offset market.

U.S. Mine Corp is spinning-off their SCM business I’ve been reading up on it and I think it’s a big deal. It’s kind of a lot, but here’s my write-up…

Best–

Millennial Falcon

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Anyone remember use, in the UK of aerated concrete? Very popular, because it was cheap. The experts said everything was fine. Until the stuff started to crumble.

And in other concrete news…

DB2

Recent research (2023) has looked into this -

Lots of research is being done to make concrete more climate friendly as well.

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Any bets that anything they discover to make concrete more durable also makes it more expensive, so it’s a non-starter, because the only thing that matters today is cheap, cheap, cheap.

Steve

I’m sure testing in the 1950s was different— nonetheless SCMs are used everywhere already— this is not new— just a new source and player in the game.

I probably should have spent more time on the history of SCM use, but it is widely used today.

It’s more similar to the clay / pozzolan products used to build to Colosseum.

The news is not whether or not there is a market for SCM— there already is— it’s the fact that US Mine Corp is spinning off part of their business as public company— and they already have the material and permits to manufacture.

It is prudent to just wait for the re-IPO / uplifting— but I think this paints the path relatively clearly. It’s a $20k investment for me and I expect it to be worth over a million in 2-5 years.

It sounds silly. I know, but “Once in a lifetime opportunity” doesn’t happen often (be definition)

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Read my link above—

It’s cheaper because the clay is a byproduct of current mining operations.

Think of the fish meal industry. Chewy. Etc.

The raw clay alone is mined in Georgia for massive profits.

And all this time I thought that Jimmy Hoffa and the Teamsters had invented the ultimate concrete additive that reduced CO2 in concrete.

Mike

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OK, here’s a new cement that seems to accomplish something. Using a “phase change” of a component, it heats itself to keep snow and ice off the pavement.

That would alleviate billions of dollars of annual maintenance on highways for 70% of the country.

There are some downsides, as mentioned towards the end of the article. Another (unmentioned) is trying to defeat the asphalt lobby which has made itself the defacto standard for most of the miles of highway. The concrete guys get to do some on/off ramps and bridges because maintenance is so much less, but mostly it’s asphalt.

Anyway, “self melting” sounds pretty cool. No report on how it changes the longevity of the material.

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Dept of Energy just committed $6B to lowering carbon emissions— one such sector listed was cement manufacturing.

Specific project awards were named— no Purebase on that list— but more of these initiatives to come with lots of cost sharing available.