Scientist believes she found the secret to Roman concrete used 2000 years ago

[Peter1469]

Scientist believes she found the secret to Roman concrete used 2000 years ago

Romans built roads 2000 years ago that can still be used today. We are lucky to get a few years out of our roads before they need major repairs. Why? The concrete.

Scientists have long puzzled over the elusive recipe for ancient Roman concrete, which has withstood the test of time better than any of the concrete that’s been poured in the 20th century. Now, Time reports that Maria Jackson from the University of Utah claims to have unravelled the mystery, and furthermore believes that the ancient Roman process could influence modern-day construction.

Jackson’s findings, published in American Mineralogist, claim the unbreakable strength of ancient Roman concrete is due to a rare chemical reaction that takes place when the mineral aluminium tobermorite is exposed to sea water. The reaction strengthens the mortar and prevents cracks from forming or widening.


The longer the concrete is submerged in sea water, the stronger it becomes, as a mineral mixture of silica oxides and lime grows between the volcanic rock aggregate, which in turns hardens all the components into a single, unyielding piece. Jackson explained how this is different from our current concrete to Time:

“Contrary to the principles of modern cement-based concrete, the Romans created a rock-like concrete that thrives in open chemical exchange with seawater.” She said, adding, “It’s a very rare occurrence in the Earth.”

This may explain the ancient observation of the Roman scientist Pliny the Elder, who wrote in 79 AD that the concrete, “as soon as it comes into contact with the waves of the sea and is submerged, becomes a single stone mass, impregnable to the waves and every day stronger.”


The Pantheon in Rome, still in use over 2,000 years after it was built, is a testament to the strength of ancient Roman concrete. Once a Roman temple, it has been in continuous use throughout history, and since the 7th century has been used as a church dedicated to “St. Mary and the Martyrs.”


Jackson notes that the Roman process was actually much more eco-friendly than our modern method, which is known to produce carbon dioxide. She believes that the old ways of concrete production could teach us a lot, but she notes that the ancient Romans had a greater access to volcanic ash, a primary ingredient, than most countries do today.

[Common]

Concrete comes in different strengths in the mix, highway mix is 5000, big construction companies are known to fudge on concrete strength when your pouring that much concrete the savings can be huge

I remember reading or being told residential concrete starts to degrade after 25 yrs, its a slow process. That doesnt mean cracks and breaks etc, just erosion.

The romans being able to overcome those shortcomings was a mystery until now, thanks for posting this

[FindersKeepers]

Concrete comes in different strengths in the mix, highway mix is 5000, big construction companies are known to fudge on concrete strength when your pouring that much concrete the savings can be huge

I remember reading or being told residential concrete starts to degrade after 25 yrs, its a slow process. That doesnt mean cracks and breaks etc, just erosion.

The romans being able to overcome those shortcomings was a mystery until now, thanks for posting this

It's fascinating, really. Too bad volcanic rock isn't available in quantities large enough to use on a regular basis today. Speaking of residential concrete, I've seen a lot of it start to degrade before 25 years, often because the crew pouring adds too much water to the mix to make it easier. And, they don't always take the time to cure it properly. I visited a friend a couple of months ago and her patio surface was spalling. She just had it poured last year. That's the problem, these crews can make it look nice right away, but it doesn't stand the test of time.

[donttread]

Scientist believes she found the secret to Roman concrete used 2000 years ago

Romans built roads 2000 years ago that can still be used today. We are lucky to get a few years out of our roads before they need major repairs. Why? The concrete.

I remember hearing something about ancient concrete being better. The scale of our concrete needs is huge, but perhaps this process could be mimiced in priority situations.

[Beevee]

In Montreal the concrete is as strong as the Mafia decides it should be.

[Hoosier8]

Very interesting finding.