Posted on 01/06/2023 10:19:27 PM PST by SunkenCiv
It's a riddle that has left engineers scratching their heads for a very long time.
How is it that Rome's famed Pantheon has stayed intact for almost 2,000 years while many modern concrete structures crumble after just a few decades?
Now, researchers may have finally discovered the secret behind ancient construction methods – and it's all to do with tiny pieces of lime that come with 'self-healing' capabilities.
Close analysis of Roman concrete has revealed tiny, bright white mineral chunks called 'lime clasts'...
And they discovered the lime may actually help the concrete 'heal' itself when it cracks or breaks.
During the hot mixing process needed to make concrete, the lime clasts become brittle – creating an easily accessible source of calcium for the rest of the concrete.
This means that when tiny cracks form in the concrete, the lime clasts react with water and create a calcium-saturated solution, which can recrystallize and quickly fill the crack.
Initially, it was thought these were present as a result of sloppy mixing practices, or using poor-quality raw materials...
To prove that this was indeed the mechanism responsible for the durability of the Roman concrete, the team produced samples of hot-mixed concrete that incorporated ancient formulations, deliberately cracked them, and then ran water through the cracks.
Within two weeks the cracks had completely healed and the water could no longer flow.
An identical chunk of concrete made without the lime never healed, and the water just kept flowing through the sample.
As a result of these successful tests, the team is working to commercialize the modified cement material.
(Excerpt) Read more at dailymail.co.uk ...
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That is neat.
I'd like to see supercharged lime clasts that can eliminate driveway cracking caused by poor base preparation before laying down the concrete slab.
It’s still the largest unreinforced concrete dome in the world.
You put up the BEST articles!
Oh wow.
The saying is “Concrete always cracks” and that is certainly true of modern concrete...you just try to control where and how much it cracks.
But then I looks at that magnificent dome sitting there for 2.000 years with nary a crack or spall and its amazing.
The Pantheon is just a marvel. An amazing building.
Everyone should visit The Pantheon!! October will be visiting the Great Pyramids!!
Initially, it was thought these were present as a result of sloppy mixing practices, or using poor-quality raw materials
Reminded me of some of the things Thor Heyerdahl found out about the genius of ancient naval architects in his construction of Ra
Haven’t seen the pyramids in person, but have been inside the Pantheon. Absolutely incredible. Even in a city like Rome, filled with numerous awe-inspiring examples of the brilliance of Roman engineering, the Pantheon stood apart for its beauty and durability.
Good post. Thanks for posting all these types of articles.
The real mystery is how the Roman use of lime influenced a Greek structure that preceded it by a 1,000 years.
Never mind - dyslexic. Read Parthenon.
Very cool. Thanks!
Not bad...considering the Pantheon has a huge hole in its roof.
I agree. It’s an incredible building. A MUST see on any visit to Rome.
And it's adorable that Roman errors were seen where none existed, even though no one alive today, even now, could reproduce the Pantheon dome.
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