Self-Healing Concrete: What Ancient Roman Concrete Can Teach Us

Hackaday ^ | April 3, 2023 | Maya Posch

[Texas Fossil]

Concrete is an incredibly useful and versatile building material on which not only today’s societies, but also the ancient Roman Empire was built. To this day Roman concrete structures can be found in mundane locations such as harbors, but also the Pantheon in Rome, which to this day forms the largest unreinforced concrete dome in existence at 43.3 meters diameter, and is in excellent condition despite being being nearly 1,900 years old.

Even as the Roman Empire fell and receded into what became the Byzantine – also known as the Eastern Roman – Empire and the world around these last remnants of Roman architecture changed and changed again, all of these concrete structures remained despite knowledge of how to construct structures like them being lost to the ages. Perhaps the most astounding thing is that even today our concrete isn’t nearly as durable, despite modern inventions such as reinforcing with rebar.

Reverse-engineering ancient Roman concrete has for decades now been the source of intense study and debate, with a recent paper by Linda M. Seymour and colleagues adding an important clue to the puzzle. Could so-called ‘hot mixing’, with pockets of reactive lime clasts inside the cured concrete provide self-healing properties?

Concrete Recipes

[Brass Lamp]

Did the Roman concrete makers do this on purpose, or was it a fortunate result of imperfect manufacturing methods? it’s remarkable either way.

I've always admired Roman engineering, but there is simply no way any craftsman of the time would know how his work would withstand the millennia. Nor could he have relied upon the examples of deeper antiquity, as there was no communication of information from his occupational predecessors. There is a type of survivor bias with which we moderns must contend when evaluating what remains of a (previous) variated subject of study. Structures which remain are remarkable for having survived, while those which did not last are somehow NOT remarkable and not held as evidentiary.

[VastRWCon]

Earlier this year I was in the keys and did the pigeon key tour at the old 7 mile bridge. They said the concrete used on the old bridge will out last the concrete used on the new bridge. That concret recipe from germany for the old bridge could stand up to the salt water but the recipe was lost. They said the old bridge will still be standing when the the new bridge will need to be replaced. Cool stuff.

[HartleyMBaldwin]

Exactly so. The stuff that wasn’t extraordinarily good is long gone. That’s exactly why I tend to question the notion that the ancients knew so much and could do so many things better than we can now. They got lucky sometimes, just like people in every era, and the rest of their works went to ruin.

[Vermont Lt]

1900 years is a long time. What happened to all of the other Roman concrete?

[Bethaneidh]

In ancient times, those who experimented and generally followed their version of the scientific method, tended to keep their research to themselves, and not proclaim it to the Unwashed much less to other possibly competing experimenters. It is disclosure that is a modern invention.

[DesertRhino]

Exactly...

[DesertRhino]

I would be open to the idea that some fairly advanced civilizations did exist before the last ice age, and what we see now is a human resurgence after the glaciers receded.
But nobody is flying UFOs out there... nobody.

[supremedoctrine]

thanks great real life recounting....my father was a concrete contractor and I helped him on his jobs many times. That was enough to scare me off wanting to do that in the building trades.

[supremedoctrine]

thanks great real life recounting....my father was a concrete contractor and I helped him on his jobs many times. That was enough to scare me off wanting to do that in the building trades.

[wgmalabama]

I did a few years doing aluminum pin & wedge basement forms and concrete. Hard work. Them forms were heavy 4 foot by 8 foot sections.

[cp124]

We build things to sell, not to last.

[TStro]

The Antikythera mechanism ( / ˌæntɪkɪˈθɪərə / AN-tih-kih-THEER-ə) is an Ancient Greek hand-powered orrery, described as the oldest known example of an analogue computer [1] [2] [3] used to predict astronomical positions and eclipses decades in advance.

Explain that anyone

[Lion Den Dan]

Yes. Gifts are given......................

Gee, Tex, I thought they were gifted.

[SunkenCiv]

The rest of the keyword, sorted:

• MIT, Harvard, Italian, and Swiss scientists re-discover why Roman concrete structures last millennia while modern concrete doesn't [01/10/2023]
• How the Pantheon has stayed intact for almost 2,000 years: Study reveals how small chunks of lime gave Roman concrete 'self-healing' capabilities [01/06/2023]
• Why was Roman Concrete Forgotten during the Middle Ages? [11/14/2021]
• Sinkhole opens near the Pantheon, revealing 2,000-year-old Roman paving stones [05/13/2020]
• Science reveals improvements in Roman building techniques [10/30/2019]
• Paleomagnetism Study Supports Pyramid Man-Made Stone [02/19/2018]
• Finding a new formula for concrete [05/28/2016]
• Back to future with Roman architectural concrete [12/19/2014]
• To improve today's concrete, do as the Romans did [06/05/2013]
• The Riddle of Ancient Roman Concrete [09/02/2011]
• Volcanic ash may have preserved Roman ruins (Good cement) [05/14/2009]
• Is the Roman Pantheon a colossal sundial? [02/05/2009]
• Researcher investigates ancient geology to understand human development, climate change [10/11/2008]
• Ancient Rome's Earliest Temple Reconstructed [03/15/2008]
• 'Caesar's superglue' find [12/04/2007]
• Research team recreates ancient underwater concrete technology [04/09/2005]

[Captain Jack Aubrey]

They were as modern then as we are today, but without refrigeration or air conditioning. Imagine.

[Romulus]

You are aware that the Roman Empire that “fell” was universally Christian?

[roadcat]

I think the ones who insult them the most are the archeaologists who insist that they worked solely with sticks and stone chisels to carve out giant granite obelisks and things of the sort.

I agree. Too many sophisticated tool marks left behind on ancient artifacts. And Egyptian archaeologists that will destroy or hide artifacts and tools that predate Egyptian peoples, that show the Egyptians came upon the artifacts later and their culture were inferior in regards to building. Newer construction was inferior, ancient construction can't be duplicated.

Tool marks show signs of lasers, computer-alignment, diamond drills etc. I believe a cataclysm many thousands of years ago happened world-wide that wiped out knowledge and talented artisans, except for monolithic builds such as the pyramids etc.

[minnesota_bound]

Dump Truck Help 😁
https://media.gab.com/system/media_attachments/files/134/666/805/playable/526cde4119f97597.mp4

[alternatives?]

Like our last congress was 88% “Christian”?

[minnesota_bound]

#20 they had to have cooling pipes inserted to keep the concrete from cracking plus all them bodies are still encased.... : )