Recent discovery: the ancient Roman concrete auto regenerate itself. This was the secret the Romans used to make their buildings 2000 years ago!

Have you ever wondered how are the ancient Roman buildings still standing today while our modern buildings seem to deteriorate so much quicker and easier?

Thanks to a recent discovery of the MIT of Boston now we know: the ancient Roman concrete auto regenerate itself. This was the secret the Romans used to make their buildings 2000 years ago!

How does this happen?

When our modern walls crack, water and humidity go inside the crack, making the whole structure weaker.

In the same situation, the ancient Roman concrete instead repairs itself. How?

The Ancient Roman walls had grains of lime in them. When water goes into the cracks, the grains of lime melt and refill the cracks!

Environmental engineer Admir Masic and his team have been studying the Roman concrete for five years and this is what their studies led to.

They have found an answer during their researches in the archaeological site of Privernum, about 100km south of Rome.

This is where they took samples of the ancient Roman concrete, made of a mix of volcanic ashes and water. And this is where they started examining the lime. 

They observed that when lime mixes with cement, it creates some grains. When these grains are mixed with water they melt and fill the cracks in the walls which occurred over time.

These grains of lime are the result of the “hot mixing”. The mix of these substances in fact, at very high temperatures (up to 250° celsius) does not allow the lime to melt, but it creates these grains instead (This is what we understood by doing some researches as “outsiders” to the subject. Please forgive us if you see any technical inaccuracies!). Here you can find more in depth and technical details.

Researchers reproduced concrete with this same process and it appeared that the concrete did regenerate itself during the experiment!

This team of the MIT of Boston proved that these grains were not there by chance, but they were created on purpose by the Romans. 

This newly discovered type of concrete has now started to be produced to be used in modern buildings!

Will we ever stop learning by the Ancient Romans?

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