We solved Roman concrete

Hosted by: Hank Green (he/him)
Lucas Principe: Writer
Heather Hess: Fact Checker
Amy Peterson: Script Editor
Madison Lynn: Videographer
Faith Schmidt: Script Supervisor
Stefan Chin: Editor
Savannah Geary: Associate Producer
Daniel Comiskey: Editorial Director
Sarah Suta: Producer
Caitlin Hofmeister: Executive Producer
Hank Green: Executive Producer
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[@Mr.b0nes]

Many people do not give ancient people enough credit for how smart they were

[@jpheitman1]

Can't shake the feeling this was an accident. Do you really think they compared concrete with quicklime to concrete without, or contrasted freshwater to seawater concrete? ...I would actually be fascinated if it turns out they did, so if you can find evidence for it, *please* post the source. The idea of Roman materials scientists is fascinating.

[@RomesPompeii]

​@@jpheitman1i mean they didn't just randomly drop concrete with quick lime into see water.

[@435cyberteam9]

@@jpheitman1 I'm fairly certain science as a whole is filled with happy little accidents. Especially back in a time where people didn't look to discover things too much, everything new came by accident. Most things we know came from an accident. Or doing something wrong and ending up with a completely different, but still interesting, result.

[@frozen7550]

​@@jpheitman1I mean the way they cured small pox. They experimented. They had the time.

[@cnacma]

@@jpheitman1I mean they may not have had fully fleshed out the scientific method but they were fully capable of process of elimination and experimentation with different materials. Humans have always done that as far back as we have records. The Roman republic (then empire) was around for a very long time. They had a robust record keeping system and written language. It’s really not that far fetched that they were constantly experimenting with materials until they discovered this mixture. It was the same process when humans discovered fire, the same process when humans discovered metallurgy. We’re not the strongest or the fastest of the animals on this planet but we have huge brains and an uncanny ability for pattern recognition.

[@techpriestmac]

Fun fact: Togas were a ceremonial attire, like a suit. The everyday wear was more in line with Tunics. So yes, they had sleeves.

[@FullMetalAlphonse]

Only in late Rome, it was commonly used as a simple garment for warmth and comfort in the early days of Rome, and was generally made of cheaper materials than it's later counterparts

[@janewright315]

Came here to say this but you were already here

[@bas-tn3um]

this depends on the era dont be anachronistic.

[@TheAllcreatorLiveArchives]

Most tunics don't have sleeves. They go over long/short sleeves, but they themselves don't have sleeves. They were more like ponchos with something to tie them around the waste. If anything people would wear togas more because they were easier to make. You gotta remember they were pretty lazy people when it came to personal image. People like to fantasize about meeting beautiful people dressed in fancy clothing in the past, but in reality even homeless people today dress better then the richest people of the past.

[@bas-tn3um]

its an anachronism anyway they only wore togas when greek culture became popularized. we even have roman writers complaining aboiut roman men wearing togas and silk clothing to escape the heat not like proper romans in their linen robes.@@TheAllcreatorLiveArchives

[@benlarge1984]

I swear every few years they have found out how to make Roman concrete

[@TeddGCM]

Right? I was thinking this myself

[@emcd]

i mean this video is a year or two old so it could just be algorithms feeding old news back to us

[@p24p14]

But they wont use it because, yknow, capitalism

[@MrJenssen]

​@@emcd considering how he mentions a 2023 study, I have my slight doubts that this video is two years old.

[@rycycle413]

​@MrJenssen march of 2023. It's kinda close to 2 years 🤷‍♂️ but he literally stated that we found a NEW ingredient for it. We first found out they used salt water. NOW, they've found quicklime. It could be an addition to what you guys remember before. Just throwing thoughts out there

[@-Kal-]

Modern masonry does use slaked lime, especially in mortar mixes. Slaked lime is hydrated quicklime (CaO + water). It's reacts more slowly and is less caustic than quicklime. There are many good reasons to add slaked lime to mortar, like increased slump with less water, less water seeping out during curing, and a lower compressive strength. Lower compressive strength may be needed to match the compressive strength of the bricks, blocks, etc. to prevent damage. Slaked lime is not typically added to concrete where high compressive strength is important. Source: masonry contractor specializing in repairs

[@FuryOfTheSwarm]

for those who don't know, while it can self-repair, its ability to resist kinetic force is far less than modern concrete.

[@Nanook128]

Do you think it would potentially be advantageous to build a structure out of conventional concrete and then top it off with a layer of the regenerating Roman concrete to protect it?

[@FuryOfTheSwarm]

@@Nanook128 no, the regenerating roman concrete then becomes redundant. The existing concrete will still decay naturally, eventually leaving only the roman concrete. Unfortunately, the two types of concrete are different and will not mix. The only forseeable benefit would be if a company were to research a method to hybridize the properties of modern and roman concrete, but that new mixture would be very niche, perhaps as a submersible steel wall, or in certain regions with considerable rain fall. The benefit is just not worth the cost though.

[@Nanook128]

@@FuryOfTheSwarm I see. I would think that the Roman concrete would protect the modern concrete underneath. Is it an issue of the water soaking past the Romen concrete and getting to the stuff under it before the Romen stuff finishes regenerating?

[@carlsiefkas4235]

I'm curious about what about the old vs the new makes it better or worse against kinetic energy. Also could that be improved with steel reinforcement. Idk that's why I'm asking

[@FuryOfTheSwarm]

modern concrete is much more compact, and has stronger binding, making it harder to separate the particles of concrete. Roman concrete is much looser, permitting kinetic force to cause more alterations that overall decrease structural stability. You can reinforce it with steel, but that makes the roman concrete redundant. Overall, modern concrete is much stronger, and its more cost effective to just repair/replace the concrete as it gets older.@@carlsiefkas4235

[@pokemfan951]

I cannot begin to explain how badly I needed to know how Roman concrete was 'self-repairing.' A book series I love used the stuff, but didn't explain what made it so unique. So thank you. Very much.

[@kenhammscousin4716]

Same

[@HighLordoftheBathroom]

Would you mind sharing the series?

[@sebastianfalcone5046]

kzbin.info/www/bejne/p32Tc3VohbeMbc0

[@GreatOrigins]

What's the book series?

[@Happy_Biker]

I'm not certain, but I'm guessing that, when exposed to heat and humidity, the quicklime is reactivated to allow for stress fractures to fill in, thus "healing" them. (That's a quick guess.)

[@disappointedfather5114]

It's been known for a while. The issue with Roman concrete is it doesn't allow you to build anywhere as tall or as strong structures at what we have, even if wtv you build will last longer.

[@abarette_]

it also doesn't go well with Steel.

[@1truthseeking8]

​@@abarette_ don't take what isn't yours

[@Kero-zc5tc]

@@1truthseeking8dawg mad over the fundamental of learning 💀 💀

[@Shade01982]

The Pantheon is 43 meters high and has stood for almost 2000 years. I think that beats pretty much anything except maybe skyscrapers...

[@disappointedfather5114]

@@Shade01982 Literally said it indeed will last longer, so I don't get your point. Yes, the point is skyscrapers. If it was better than today's concrete, we would've already switched to it back when we studied it. Thing is, it doesn't really allow you to work with rebar for strengthening, so again, you can't build structures as tall and safe with it than the modern stuff.

[@CowboybubPercussion]

There is a little misinformation here, just because yes, although Roman concrete can self repair and things, it does not make the concrete stronger, or better in some applications. Our modern concrete columns can withstand ranges from 4000-5000 PSI, Roman concrete only can withstand 1160 PSi. Modern Portland cement is made through a process to make a product called Clinker, which is made from baking lime stone and clay like materials into a kiln at extremely high pressures, much higher then the Roman’s could’ve ever done. Then the Clinker is ground up and adding 2-3% Gypsum to make Portland cement. We then mix this with aggregates like rocks and sand as well as fresh water for use in making concrete. The Roman’s concrete is a much more primitive hand mixed mixture consisting of unbaked, hand mixed lime, ashes shells, and aggregates. Being it was hand mixed, it wasn’t mixed thoroughly. What you get is a weaker structure that still has unreacted lime in the mixture, and being it lacks clay and harsh pressures, it was weaker as a result, but when it does crack, the concrete heals itself in contact with water. So, choose your poison.

[@jillthompson1248]

Then how did their stuff stay up usable functioning still today or does it get stronger better with age or something. Or do we not have the real recipe for it or could sea water actually be the secret I don’t know

[@Kero-zc5tc]

⁠@@jillthompson1248…because it self heals, the thing is that they aren’t as strong, you wouldn’t be able to drive cars over them without causing damage (which may heal but it can’t heal limitlessly). They stay standing because Roman monuments either are only walked on or are abandoned

[@jillthompson1248]

@@Kero-zc5tc I thought they were driven on like bridges in England

[@jillthompson1248]

@@Kero-zc5tc ok I didn’t know just knew Roman’s were there

[@smockboy]

@@jillthompson1248 The oldest bridges in the UK that can be driven across (as opposed to only allowing foot traffic or equestrian traffic) date back to the medieval period which starts around 600 years after the Romans had left - and most of them are from toward the end of the medieval period almost a 1000 years later. It's further worth noting that all of those bridges had significant adaptations made to them in the modern day to make them suitable for vehicular traffic so we're not driving over the original construction.

[@andrewpierce5065]

Note from a Civil Engineer: Engineers have known this for years. One of the main reasons modern concrete doesn't use this method, are the chlorides within the saltwater hasten the degradation of any steel reinforcement within. Unreinforced concrete is uncommon in anything apart from mass foundations, and DEFINITELY wouldn't be used in the bridge he showed.

[@TheGameChallenger]

Damn that's really important to know. He made it seem like the current engineers were all just stupid

[@J.petty124]

Modern engineers would build the pantheon with steel reinforcement & claim it would fall apart without it

[@edg3818]

There are ways around this though, different materials for the reinforcements could be used or use rod or mesh that've been coated. Also degradation of modern concrete can expose the reinforcements to corrosion as well, I see it all the time in Detroit.

[@theguitarist1703]

⁠​⁠@@edg3818What material(s) would you suggest using? Is there another material that has the same (or similar enough) properties as steel to ensure the structures you build don’t collapse under stress? What would it cost compared to steel?

[@andrewpierce5065]

@@theguitarist1703 you've nailed it. It's all about the cost. Stainless steel reinforcement can be used, but it's really expensive, and for this reason is uncommon. There's also this phenomenon called bi-metallic corrosion, which means if you use stainless for one thing, you're locked into it for everything. It's really interesting actually, it's because the stainless steel forms a half cell with other metals which are in/around the concrete.

[@G4NG5TABR01Y]

Roman concrete really says "NANOMACHINES SON"

[@mptran217]

“You can’t erode me Jack.”

[@jakkakasunset5485]

"I have a dream! That one day, every building in this nation can self heal its own concrete. A concrete that's truly free, dammit! A concrete with Quicklime, not rebar! With sea water, not just fresh! Where durability is improved greatly, in the Roman Concrete!"

[@curple3]

"THEY HARDEN IN RESPONSE TO AQUATIC TRAUMA"

[@notusneo]

Love this reply section

[@nicholausedwardwijaya8822]

You win, you win

[@lukechapin5563]

This is right, but we don't use it because the salt rusts rebar that's put inside, so it's overall weaker.

[@lisabek72]

So they didn't use rebar.....buildings are still standing

[@lukechapin5563]

@@lisabek72 True, their buildings are still standing. But we don't use their concrete recipe for a reason, and it's not because we recently discovered the recipe. The difference between our concrete and theirs is that their concrete lasts much longer, but has less capacity for weight. Our concrete can handle much more stress, but lasts less long, due to not repairing itself. The rebar reinforces concrete's main weakness. I forget what the word for it is, but concrete is weak to being pulled apart, and is strong against compression. Rebar reinforces the concrete, making it stronger at withstanding being pulled apart.

[@SirMuffin1]

​@@lukechapin5563 You should build the Yap temple Tldr ; they dont use the recipe because it 2x the price and they cant charge you 5 years down the line to redo it and make more $$$ So greed is the reason they don't use it.

[@lukechapin5563]

@@SirMuffin1 True, I didn't take money into account.

[@kingol4801]

@@SirMuffin1 ? That is just typical conspiracy theory stuff. In actuality, practical applications are the reason

[@grace52775]

You know, it would also reduce everyone needing to wait at construction zones. We can prevent all the idol cars from giving off emissions (and, save us all time and a headache!).

[@jonathanboutell8767]

As a road engineer, I feel that I should say that the reason that specifically roads crack is usually not because the concrete has degraded, but because the ground beneath it has. Self-healing concrete can only go so far in this case because it doesn't help the underlying issue

[@1Adamrpg]

True, but self-repair working for 1000 years is way better than having to petition the govt to fix roads every 50 :D

[@somepunkinthecomments471]

Every fifty? They repave the roads every year here yet there's still somehow potholes everywhere.

[@BreadAccountant]

​@@somepunkinthecomments471 ... it's cause of cars. Romans didn't have 2 ton machines going at 40 all day every day

[@BreadAccountant]

​@@1Adamrpg cars are the reason why the roads get destroyed

[@ericbeaudry8118]

Road degradation is caused by two things: repeated dynamic load measured in terms of ESALs (equivalent single axle loads) and freeze thaw cycles from the changing of the seasons

[@JCDofNYC]

As Caesar famously said, "I came, I saw, I concreted."

[@witchhunter6755]

He never said that >:( I demand one concrete source that states as much

[@nahommerk9493]

​@@witchhunter6755😂😂 nice

[@JCDofNYC]

@@witchhunter6755 it has long been said that "all roads lead to Rome", and that those roads were made at Caesar's direction, and he insisted they be paved with concrete. 😐

[@FarisYKamal]

I came 😏

[@Obelixlxxvi]

😂

[@darksavant3571]

Well, the reason that the Roman structures are still up is that there have been initiatives to maintain the structures. Many of the structures would not exist currently if over the years there has not been repairs to them.

[@CharliePryor]

Yes. It does help with not having to repave stuff all the time… which is probably why it’ll never be mainstream in America - because the shortsighted will acknowledge a huge threat to their constant annual work contracts and budgets.

[@justme42300]

Even in death, the Romans still flex.

[@ventithedrunk9506]

With all those muscular statues they left behind, they definitely still do

[@marbelentertainment4761]

After they stole Greek architecture and design

[@kreebzz]

​​@@marbelentertainment4761man.. the nice, simple, and funny joke is ruined now.

[@garthdrewl9879]

@@marbelentertainment4761bahh you suck, they did it better, Roman’s flex again.

[@garthdrewl9879]

@@marbelentertainment4761bahh you suck, they did it better, Roman’s flex again.

[@rue6914]

OMG! I just came back from a trip to Italy. The ruins of ancient Roman buildings showed the horizontal texturing of some pillars and they had that same quicklime pattern so cool

[@xxtoxii9615]

it may just be breccia if it were pillars. it looks similar but its rock

[@Jamesah]

It's most plausible that this "Roman" concrete is a derivative of Egyptian concrete. The Romans learned to make concrete from the Egyptians... See the pyramids, there's a theory they were made similarly to concrete.

[@skelitonking117]

@@Jamesah my guy, the pyramids are quarry cut stone lol

[@girl6girl6]

@@Jamesah that's not "some theory"... that's YOUR theory bruh. And uh...no. The Pyramid stones were quarried.

[@Jamesah]

​@@skelitonking117 Welp a scientist Charles Bremner believes the pyramids were built with concrete rather than rocks. I can't post the link so you can google it.

[@lkdominator4088]

Issue is.Salt water has declared war agaisnt almosy ALL metals. Yea. Not just iron. So it can and will degrade any metals put inside it

[@navarrjenkins7648]

What’s crazy is they probably came by this naturally and accidentally. I’m not taking credit away from them, but it’s crazy how something so seemingly simple can go unused for so long.

[@kingol4801]

It is unused for a reason. Modern concrete can withstand much greater pressures, that it is not even a contest. Likewise, Roman concrete would not support metal within it at all, which is 101 of modern architecture. Concrete is all well and good, but the moment you need the building to withstand stress and build higher…. Or have vehicles run over it repeatedly… Roman concrete just falls flat

[@navarrjenkins7648]

@@kingol4801Would it not be better for road than the assault we currently use? I feel like potholes would occur less with a concrete that can repair itself.

[@ALittleMessi]

​@navarrjenkins7648 as previously stated, roman concrete cannot take nearly as much pressure as required. Have you ever seen a semi truck? They would crack it immediately. It would also be prohibitively expensive compared to asphalt, and take an enormous amount of time to install, fix, and re-install. This is all while roman concrete can sustain about 800 psi, and modern concrete 4000. There's a reason we don't have concrete roads everywhere.

[@mikec63136]

The DOT have perfected a modern concrete that breaks down in 3 years!

[@Quasar0406]

😮

[@pinkpugginz]

that's on purpose so all the contractor companies keep getting paid to redo it 😂

[@Mason32800]

Also takes 3 years to install

[@A-ii5dp]

I don't think the Romans had 80,000 pound carriages running at 70 mph on their concrete though.

[@LamNguyen-fj2op]

@@A-ii5dp It has not been tested yet.

[@JadenYu]

Bro enchanted the brick with mending

[@Anon_y_mouse_the_only]

Yes. Just yes.

[@thewhate2294]

You win

[@Imperial_Squid]

Play. Literally. Any. Other. Game.

[@CheeseMiser]

​@@Imperial_Squidwhy.

[@KidNamedBlue_]

​@@Imperial_Squid. Literally. Nobody. Asked.

[@desertvoyeur]

So true, and kudos to them. Left out is the fact that they didn’t use steel reinforcement. As the minute cracks occur, water gets in and an exponential increase of rust corrosion begins, the expansion of which causes even further cracking, eventually destroying the structural integrity of the structure. I believe that we still haven’t found a non carcinogenic reinforcement material to replace steel. Could be wrong, though.

[@0rbnotacus]

The sad part is that it's going to be years until this is actually used, if at all. Change costs money, and companies cut corners so hard anymore, they can find the corner of a round room.

[@daveharrison84]

Salt will corrode steel. Romans had unreinforced concrete, which works for compression-only structures like domes. You need steel reinforcement that doesn't rust to make beams and slabs.

[@Eduardo-wd3dv]

that's interesting, though surely this is still a breakthrough for those applications of compression.

[@ihcend]

@@Eduardo-wd3dv not really roman concrete has a compressive strength of around 1100 psi, while modern structures require concrete with 2500-4000 psi.

[@fx-studio]

Stainless steel rebar or Basalt rebar is the answer.

[@Ghalaghor_McAllistor]

Now we need to discover an alloy that is as strong or stronger than steel while at the same time rust proof when it comes to sea salt.

[@drkclshr]

@@Ghalaghor_McAllistor it also needs to be as cheap

[@XPI888]

"Just because people are dead doesn't mean they are stupid." - David Pye

[@gibbsm]

it does mean they lack ones of years, to thousands of years of missing data to use in making anything. So I say time does matter.

[@robertbrodie5183]

most stupid people i meet are the alive ones

[@erinjaeger6169]

except those idiots on tiktok getting killed cuz some stupid challenge

[@peterkilbridge6523]

Archimedes, Galileo, Leonardo, Newton, and Richard P. Feynman are all dead, last time I checked. ✔️

[@gimmedataids]

​​@@gibbsm lol @ "ones of years". And that missing data and experience does not mean they were stupid.

[@VladTepesh409]

One of my buddies at a concrete testing facility, who's enamored by all things concrete, flipped his wig when he heard about this. Absolutely amazing!

[@caylya7869]

Many of this has been known by engineers. It’s just isn’t used because it doesn’t really work for the structure of bridges. Also it affects the structure of the steel that’s reinforcing the concrete.

[@milohdd]

There's another overlooked aspect to this: they didn't use steel. Steel reinforced concrete is much much stronger, but also degrades far faster thanks to rusting creating tension in the concrete. Because they mostly used rocks and pebbles as aggregate this doesn't happen in the Roman stuff.

[@nocare]

Add to this, that all roman structures had to be built in compression since concrete doesnt work in tension without steel reinforcement. And that roman structures saw much lower levels of general use, compared to what we demand modern structures to endure. Along with their climate being rather forgiving to structural integrity. As well as most roman structures having still been destroyed long ago. It's kind of like saying all old lightbulbs are better by looking at the handful of examples that have lasted 100 years and ignoring every reason they survived and perform worse.

[@BLAQFiniks]

​@@nocare on lightbulbs: as I've heard, even first bulbs were made to last very long time... but it wasn't feisable for profits, therefore, bulbs were down-engendered to be replaced more often, aka more money for the manufacturer~

[@nocare]

​@@BLAQFiniks the oldest ever light bulbs are all older than the lightbulb cartel by about 20 years. The cartel agreed all bulbs should have lifespan reduced from the best at, 2500 hours to 1000 hours as a form of planned obsolescence. however either age is nothing compared to the 100-120 year lifespan of the oldest incandescent light bulbs which were made before the cartel even existed. The cartel fell apart when world war II happened. Yet the 1000 hour limit was kept because the limit was not out of greed. They set the prices out of greed and would happily have charged 3 times as much for 2500 hour bulbs if those were the best design. 1000 hour light bulbs produce more light per watt of energy they consume and so are more efficient than 2500 bulbs by enough to be significant. You also needed multiple 2500 bulbs or bigger more expensive ones in order to get the same brightness from them. So just like concrete there are tradeoffs to be had between diffrent characteristics. Lifespan is not the end all be all and a long lasting product is not necessarily the best product. We can make 100 year incandescents but they aren't nearly as useful as a 1000 hour one is. Roman concrete isn't better its just diffrent and doesn't meet today's needs.

[@TheAnantaSesa]

​@@nocareI didn't know this. Nice to know it wasn't as bad/corrupt as everyone thought all this time.

[@nocare]

​@@TheAnantaSesa Yeah, it makes a nice story to have them do it for purely corrupt reasons but thats not exactly how it went. Still, its not like they didn't benefit, especially from no price competition.

[@Kimmie6772]

People also underestimate how much care goes into trying to preserve these historical landmarks. The pyramids in the Yucatan, for example, are having problems with too much foot traffic over the steps, causing it to erode over time. If there is a rule surrounding a display or building, there is a reason for it.

[@Dollightful]

This is awesome!! I hope we can all switch over to the Roman concrete recipe! 😀

[@stoptryingtomakemeusemynam7829]

We can't. He left out several of the weaknesses of Roman concrete.

[@KroganCharr]

In short: Modern concrete is usually reinforced with steel rebar to make it stronger. The roman formula relies on salt water which would degrade the rebar. So, this "self-repairing" property only really works in unreinforced concrete, which is not suitable for most modern applications.

[@warrmalaski8570]

The reason buildings last 50 years is the rebar we add to it. The rebar makes for a lot stronger structure. But as it rusts the rebar expands cracking the concrete. The centuries-old structures are pure concrete. Which would fall apart under the modern lodes required today.

[@user-up7nb6id1f]

And we nowadays put MUCH more stress and usage on our roads and structures than before - as well as having a mandate for it to be as cheap as possible while also just strong enough - which requires efficient usage of concrete. Romans basically overbuilt everything and that’s why it holds up for eons. A famous engineer joke is that anyone can build a bridge but it takes a modern mechanic to build a bridge that barely stands. Which is fair enough. Ofc also we now have 2 ton vehicles and hundred-story skyscrapers, not a requirement the ancients had to deal with.

[@networknomad5600]

50 years? Dude we’re lucky if reinforced concrete structures last 10 years without significant repair.

[@BaeBunni]

Yea but there are plenty of things we can make that crack often but wouldn't have a loadbearing structure like sidewalks and such. Unless you are tending to handcart several tons of tungsten around

[@Connie_cpu]

​@@BaeBunni sidewalks usually crack due to tree roots, I don't think even Roman concrete will stand up to the relentless pressures of life finding a way.

[@christianwiese9887]

still, the self healing effect can possibly delay the rusting of the rebar. and why is tebar made from iron? can't you use tensioned polymer threads? or polymer coated iron?

[@wiisportswithtea.3736]

POV: Romans come in clutch 2000 years later:

[@urgneos]

they flexing on us from the grave bro

[@thepsychoticone615]

@masterblaster9091 u need more school

[@rynxuz]

when is greek fire’s turn i wonder

[@willyb7353]

​@@rynxuz Basically Greek Napalm, Right?

[@justanotherrandomdude2441]

@@willyb7353 It might just be napalm for all we know. We’ll probably never rediscover Greek Fire *knowingly* cause we know nothing about the recipe unlike Roman concrete.

[@abhilashsridhara6343]

Concrete with quicklime is still used in parts of rural India. There must definitely be some others Asian countries that still use this. This can't have been "lost to the ages". It has a lot of drawbacks. It can't be used with rebars that reinforce concrete making it only suitable for small structures unless we build everything with large stones. Doing so requires so much stone that mining for it would cause many times the pollution

[@markhackett2449]

Problem is- for highrise structures steel i-beams are required, the salt water will deteriorate the steel , so this won't work for construction that requires steel gerders and beams.

[@dy7296]

"Nanolimes, son. They harden in response to rain corrosion."

[@kingking-ci1gf]

Making the mother of all concrete here, cant fret over every cement

[@pirilon78]

Lime, its the DNA of the concrete

[@okayboozy]

Read this like Tay zonday singing chocolate rain

[@Bootystank99659]

This made me go ahehe gigl 😊😊

[@fx0001]

"You cant hurt me, erosion" Proceeds to try to wear "What did I just say?" **Launches the rain into the atmosphere**

[@Volelemo190]

Better for weathering, worse for heavy construction

[@corgamargetokodra7056]

Wanted to say that. Because the salt in this mixtures let the steel components rust away

[@CalmClamFam]

Yeah I always think the cons of using Roman concrete depending on the build. It definitely is unique and should be considered in certain situations

[@Life_is_miraculus]

​@@corgamargetokodra7056 I have a question regarding that, if Roman buildings made without steal can withstand for thousands of years then can't we just eliminate the steel in construction and just use Roman concrete for bridges etc. (I'm not an engineer just a curious guy)

[@ericm5315]

Our modern structures need the reinforcement due to their size. In smaller buildings, yeah you could get away without rebar but in larger buildings, no freaking way.@@Life_is_miraculus

[@Life_is_miraculus]

@@ericm5315 I see so roman bridges are a no go then 😮‍💨 (btw thanks for the reply)

[@13jorino]

I am so glad you found out a very effective way that won't be used. In fact, somebody might now dye for it.

[@JigsawSaysHello]

Ancient people weren't stupid. It's time people give ancient people the respect they deserve.

[@Rudilsa80]

Now, time for me to builed a roman wall in my garden. Been contemplating how to do it. Glad I waited.

[@FullCircleTravis]

You can write hot gossip on your wall.

[@mewv3]

​@@FullCircleTravis lol!

[@commenter621]

For real?

[@Rudilsa80]

@@FullCircleTravis hell yeah, the Romans also invented graffiti. Keeping a theme real . 🤣

[@jasonbrecht8572]

@Frau Haertner Are you perchance related to Hadrian? 😉

[@raygagnon4809]

Just imagine a fallout scenario happens and the only hint of how society was like pre war is some regeneration concrete

[@aceman0000099]

That's stupid

[@ds3356]

From thousands of years ago 😂

[@oliviatilleman8055]

​@Chimpin Out ?

[@beesaregreatittheyprns2875]

​@@scoobert69 "green propoganda"?

[@aceman0000099]

@Chimpin Out nuclear apocalypse is not the same as climate change

[@lt2143]

There's no question that ancient civilizations were very accomplished and knowledgeable! Their creations still exist and inspires the modern world!

[@xxsgt_tomaxx8432]

Good to see you’re uploading again!

[@Vernas_R]

And in that same exact study, for I read it, there's the small issue with how heavy our vehicles are.

[@jare2067]

yea i wonder if it can withstand a million cars driving over it a day

[@Vernas_R]

@@jare2067 Yeah.. now using it in buildings might have some merit, but only the smaller ones.

[@manohousing5237]

​@@jare2067you dont drive over a garden shed's walls do you?

[@jare2067]

@@manohousing5237 you realize they use it in construction of bridges and highways right

[@sveltergamer5934]

It would be great for a small home 🏡🏠

[@Breadmaker332]

Hearing someone say everybody in Rome wore togas is like somebody from the future saying that everybody in the modern world always wore three piece suits.

[@sadroses2]

really? what did they wear day to day then? togas look comfy, like lounge wear!

[@kellydalstok8900]

@@sadroses2 a tunic

[@Breadmaker332]

@@sadroses2 Roman's would more often than not wear different types of tunics which are far more comfortable and easier to wear. A toga would be too hard for someone to get around the streets of Rome in, too much having to worry about dragging robes.

[@miladragon]

Also, togas like kind of have sleeves? At least one, that is

[@miladragon]

​@@sadroses2 they wore tunics. The problem with togas is they're not so much worn as balanced. They were certainly more skilled than us, but still they fall off, drag, etc. Not to mention, it takes two slaves to put the thing on

[@myfaceismyshield5963]

Most Romans actually wore tunicas, which had short sleeves. Togas on the other hand were A) only for rich people, and B) only for parties or official or ceremonial events like court hearings or marriages. Even rich senators mostly wore tunicas, which are practically a t-shirt style short dress, especially when working on something like concrete or asphalt (which they also had, but not for roads), or even just going to the forum to get groceries or something. You didn't want your toga to get messy, and a toga isn't a terribly practical outfit in the first place.

[@MathematicalMan]

Something to note. 1. Roman concrete self heals. There are chunks of limestone deposits in the concrete that will break down when the structure cracks, somehow molding itself into the cracks, which allows the structure to naturally repair itself. 2. This was no accident. The romans were notorious for perfecting pre-existing tools and materials. 3. It's too expensive to use nowadays.

[@ogsemsniper185]

“hold on, i need to water my house”

[@mrpablomx]

Rain?

[@ogsemsniper185]

@@mrpablomx What if you live in a place that rains rarely?

[@benjaminthejump5484]

​@@ogsemsniper185then it's just going to be normal concrete bro

[@ogsemsniper185]

@@benjaminthejump5484 Do you not understand what jokes are?

[@benjaminthejump5484]

@@ogsemsniper185 Yeah bro but its not a very good one

[@killrbunn3]

A lot of coastal towns have had this figured out for a while. There's an old quicklime plant near me that was in use in the 1800s - quicklime was most commonly used for flooring around here.

[@rubbishprophet]

They knew quicklime was great, but probably didn’t know why exactly.

[@Ezullof]

@@rubbishprophet And that's exactly what this study is about. We knew that the Romans made concrete like this, but also in various other ways depending on the needs and the available materials. But we didn't know how exactly it worked. Knowing how it works makes it possible to imagine alternative materials with the same behavior so the process can be industrialized and adapted to modern constraints. It's basically the same thing as with Damascus steel. Understanding the process meant that we could use the knowledge to make cheaper and more varied Damascus patterns.

[@davidtuttle7556]

@@paulgauthier7033no but understanding how wootz/Damascus was produced adds a lot of understanding to the materials science behind steel production.

[@asome457]

You think they just figured that out? All the major governments know this stuff, but how could they take more tax money from us if they only ever had to replace a road every 100+ years?

[@strhaivenswr]

It's not specifically the use of quick lime because we have always used it too it's the fact that it's not mixed in as a powder like we do they add it in as chunks and powder so its not 100% dissolved into the concrete mixture in the beginning as is with .modern day comcrete

[@emily5902]

I’m going to send this to my middle school art teacher. She’ll be so excited!

[@BifMcAwesome]

Fun Fact: Greenhouse gases have infinitesimally negligible effect on climate. Global climate was warmer in the Roman era than it is currently.

[@germanomagnone]

is really incredible to think that the Romans had this "self -regenerating" concrete.

[@begintothink]

Every concrete structure for the last 50+ years has had that same ability.

[@oddkill3539]

@@begintothink I wish that were true. I see so many things falling apart in my area that are made of concrete

[@daniellaytonmusic9865]

​@@begintothink noooo it has not.

[@cocknball2732]

People were 10x smarter than we’ll ever be

[@ESSBrew]

@@oddkill3539 THats cuz they are 51 years old.,

[@hi14993]

From what I, a layman, understand, it is able to continuously heal itself but sacrifices some structural strength to do so. Good for long term structures with moderate loads/traffic but bad if you have a need for heavier use.

[@ethanharman9584]

Beyond just strength loss, the Lime that lets it heal also corrodes metals, meaning you can’t use rebar reinforcements. Further, when the Lime activated it leaves small pockets In the material, risking creating structural weaknesses, since the distribution of the lime pockets are more or less uncontrollable, if you made a building out of it you could get unlucky and the entire thing falls down killing everyone inside during its first rainstorm because one section of the foundation had extra lime. (Or you have to make it with so little extra lime that it’s not worth loosing the benefits of modern concrete)

[@NazadusVoldure]

Yeah, there's a million reasons we wouldn't want to use the ancient stuff. It's nifty for it's time period - but for modern uses it's practically useless. People like to fantasize about how ancient folks were somehow magically smarter than us and used better things but in reality - we've advanced considerably. The majority of people's examples of this are almost exclusively when cities do something too cheap and go against recommendations (such as using cold asphalt instead of hot asphalt only to have the cold keep breaking down over and over). Or not using appropriate grades and then wondering why it always seems to break.

[@night8285]

How about roads, sidewalks, pathways etc?

[@stlchucko]

@@night8285 Roads need strength. “Roman” concrete would likely break away faster than it could repair itself.

[@night8285]

@@stlchucko Doesn't seem modern concrete is much stronger than Roman concrete tho

[@ismeal231]

Saltwater being used for Roman concrete seems like the main reason why modern buildings shouldn't use it. It's great if you build everything out of wood and stone, the rain will repair the concrete and ensure the building stands almost indefinitely. Buildings nowadays, however, have not so insignificant amount of steel and other metals in them. The rain reactivating the Lyme inside the concrete will corrode any metal near it way faster than modern concrete. It would be interesting if you could create a layered composite concrete, though. Like have a layer of roman concrete sandwiched in between 2 layers of high grade modern concrete.

[@CavemanJim11]

The coolest part of this is that all the companies have agreed not to patent it

[@winters4147]

I direct you to Veritasium's video on concrete, explaining that we've known this for a while, and don't employ this on large scale for economical reasons.

[@AlphaWolfShade]

If I had a penny for every time someone shouted about unlocking the secretes of Roman concrete, then I would have a few dollars already.

[@jacobrosenzweig6994]

They don't care, it's just for views. That's the unfortunate state of media today.

[@ryucartel351]

Modern humans choose profitability over quality. As long as it works well enough and makes as much money as possible, good nuff.

[@davidtuttle7556]

@@ryucartel351it’s less about profitability and more about the greater availability of Portland and other types of cement over quicklime.

[@gorenewable]

@@ryucartel351 It must because it looped like 5 times while I read this thread 😅

[@Ajibolaa]

They also crushed up sea shells and added it to their concrete and you might ask why. Cause sea shells also acted like a quick easy version of quick lime and also sea shells have some minerals in them that also helped strengthen the concrete. ❤❤

[@aaronhumphrey2009]

The shells were likely burned and crushed into the mix to add quicklime

[@HunterAnsorge-ok9jk]

Calcium not lime... seashells are made of the same stuff as our bones.

[@ymir8607]

Seashells are made out of calcium carbonate, guess what limestone contains. Ding ding ding Calcium Carbonate from tiny fossils, shell fragments and other fossilized debris.

[@Fun_Dips]

This roman concrete superiority is popular science bs. It takes decades to centuries OF CONSTANT AND REGULAR water saturation for it to gain its full strength. If you plan on rebar reinforcing that concrete, or god forbid...using it in a location that freezes regularly, saturation is the last thing you want. And before you argue that it's self-healing, said healing takes another few decades for the concrete to re-crystallize. In poor conditions, said roman concrete will be gravel by the time that healing comes into play.

[@hypno9022]

@@HunterAnsorge-ok9jk Moron

[@AndrewElgert]

All concrete is strong in compression, but weak under tension. That means that any forces pulling it apart would degrade it and cause it to crumble. We reinforce modern concrete, typically with steel, to keep it strong under tension as well. Roman concrete wasn't reinforced and its chemical processes would be caustic on steel. If we wanted to bring back Roman concrete for modern construction, we'd need a strong & durable reinforcing material that didn't rust so easily like steel does.

[@jamesmyatt354]

If you just go back to the 1920s and 30s they made almost indestructible concrete by having cleaner sand in the mix. It’s too long of a process to get it that clean since after WWII.

[@UberTheRandom]

Part of our issue is that we use rebar in ours. Makes the concrete stronger and gives us more applications, but also gives the concrete a much shorter life span due to rust.

[@GoldenGearGrinder]

We can use modern concrete in large scale buildings, like skyscrappers and the like, but use roman concrete for smaller projects, like roads, sidewalks, schools, basiclly anything that is no higher than three stories tall.

[@justingould2020]

We tend to use a lot less concrete because of this too, where as Roman structures were often overengineered. A big mass of concrete is gonna last longer than the useful life of the project.

[@nathanielbowman8034]

Fiberglass rebar might help

[@girl6girl6]

@@nathanielbowman8034 🤦🏾‍♀️

[@stringlarson1247]

Hence the green coating on good/expensive rebar.

[@BaxterAndLunala]

Big Concrete: "Why won't you degrade!?" Ancient Roman concrete: "You can't hurt me, Jack. Nanomachines, son."

[@corsomaximahu69]

STANDING HERE, I REALIZE

[@psf_dioufmaulana3040]

YOU'RE JUST LIKE

[@mutebro7523]

DAMN BRO TOOK ME 2 SECS

[@corsomaximahu69]

@@psf_dioufmaulana3040 TRYING TO MAKE HISTORY

[@koathekid8255]

@@psf_dioufmaulana3040ME, TRYING TO MAKE HISTORY

[@GlenBradley]

You’re the first person in one of these videos who actually explained why it was self-repairing. Thank you.

[@AmazingAutist]

They all mentioned that it has something to do with limestone in the mixture. Which videos where you watching?

[@angterrastriker6535]

I heard it first from the distractible podcast

[@zeddybear257]

When it’s necessary, humans can be exceptionally resourceful.

[@EvaSadana-dd7vs]

Are we just overlooking the fact that it uses saltwater instead of fresh water?! Like yes it's going to in general reduce carbon emissions and that's awesome. It also means we're most likely going to have to replace concrete less. How ever the fact it uses the most accessible form of water is kinda awesome for conserving freshwater for consumption.

[@SurjeetKumar-cl7xj]

Self repairing concrete : Politicians' worst nightmare.

[@child7482]

Was looking for this comment

[@rudmillahnowrin9151]

kzbin.info/www/bejne/nKndomSeqLWli5Isi=Z96jiy_nngFh7sfO

[@Rock_Appreciator]

BuT wHaT aBoUt ThE jObS

[@clifftrieling6052]

Belgians foaming at the mouth at the mere notion of self-healing concrete😂

[@JackCrossSama]

A product can be good but not too good.

[@kal2598]

The idea that Rome is and has been healing itself for so long is insane

[@mrtoast244]

Rome wasn't fixed in a day

[@mfsusanoo7238]

Right

[@alyssa09485]

When they say "nature is healing" this is what they meant

[@TheAnnoyingBoss]

They figured out comcrete really well yet couldnt figure out how to stop their entire civilization from collapsing due to rampant degeneracy and satanic behaviors eroding away their societies structure as it slowly sunk into the abyss

[@JoseRamirez-yh2ll]

Sadly, it'll never make a full recovery

[@user-pq5hq6rd2j]

Wow! I remember reading that roman concrete was still a mystery to us! So clever

[@johnwyman6126]

Cement is made to go through the lime cycle. The first part of that cycle is heating limestone to the point that carbon dioxide exits the stone. This is now called quicklime. When you add water to the quicklime, It takes carbon dioxide back out of the atmosphere to turn the cement back into limestone. I wouldn't doubt if the people that accounted for the greenhouse gas emissions only counted the first part of this cycle and not the second.

[@TrainsandRockets]

As a civil engineer I would like to point out few things: 1) They were made with many times more budget w.r.t. the utility and couldn't be economical today and today construction is done with low factor of safety. 2) They were long lasting in static loads, but modern construction is also good in dynamic loads like fast moving trucks on a bridge, heavy machines and wind vibrating the tall buildings etc. 3) They were made to last untill they expect their empire to last, today they made buildings for 50 to 100 years in mind. 4) If Engineers now were given similar budget and similar time, we will build more efficient, more strong, longer lasting, and more earthquake resistant structures. But they ask to make faster and and in less budget. Some points may sound redundant but read again. 👍🏼

[@allyperfectcosima5472]

If it's good for static loads would it possibly be a good solution for single/double home residential foundations? Or for single story building foundations in general?

[@TrainsandRockets]

@@allyperfectcosima5472 For a single storey building its more than enough... Only tall buildings need extra care while considering wind and seismic loads and hence, flexibility comes into play.

[@allyperfectcosima5472]

@@TrainsandRockets oh cool! Do you think it would be worth it in these sorts of applications? I'm thinking especially in areas that might experience a lot of erosion/moisture?

[@TrainsandRockets]

@@allyperfectcosima5472 if there is moisture present there must be lots of dissolved chemicals also. So a study must be conducted on the soil in the construction area to decide if it will be able to resist chemical corrosion involved.

[@allyperfectcosima5472]

@@TrainsandRockets oh, cool! I never would have even thought about that being an aspect that would be factored in! Thank you so much for taking the time to share a little bit of your expertise with me 🥰

[@aitzi6732]

We use reinforced concrete, that adds steel bars to the equation, increasing the flexibility allowing the material to work not only by compression, but with traction too. Lime and steel don't work well together (lime corrodes steel), that means we cannot use it in the structures we do today. We could use it in structures without steel, designed to work by compression and they will need thick walls, will limited in high and the layout will be very compromised. It is good to check it out and see when and where we could use it still. To find another material to reinforce it? 🤔

[@armi999]

Definitely worth exploring potential uses. It is definitely important to remember it doesn't have the same properties as the modern stuff, so it can't be used in the same way.

[@LuckyBaldwin777]

Think stainless rebar and welded wire mesh. The problem with that is, the cost would be astronomical.

[@andyrwebman]

Well, given that I've been hearing about the potential of carbon nanotubes for so long, I decided to Google "Carbon Nanotube Reinforced Concrete". I suggest folk do the same. It certainly exists as a concept.

[@g3heathen209]

Carbon fiber rebar?

[@kellysmyth2337]

Bamboo?

[@zerokiryuu3387]

That's CRAZY! I was just doing research on this some years ago, and was hoping when we'd get the mixture. This is gonna be revolutionary! Spread the word!!!

[@O2F2]

It would be great for roads and such, but due to it hurting rebar you couldn't build a skyscraper out of it or anything

[@ALittleMessi]

​@O2F2 It's not really great for roads. Roman concrete couldn't handle the pressures of our vehicles constantly driving over them. It would be great for something like sidewalks, which at least in the USA, notoriously get cracked and broken and are left like that.

[@O2F2]

@@ALittleMessi That's true. I wonder if you could edit it somewhat to make it more similar to modern concrete but with the self-healing properties. That might be better for actual roads.

[@ALittleMessi]

@@O2F2 there's also the issue that the self healing means three things. 1, the original was brittle enough to break. 2, it's likely to get pressured by whatever did it the first time. 3, the healed concrete is even weaker than the og. It sounds great to have "super healing concrete" but it's not like some sci fi material, it's more similar to filling in a crack with some glue. It's water tight, but not really healed

[@O2F2]

@@ALittleMessi Yea. Looks like our cities are gonna have to step in and *gasp* actually fix their roads. It would be nice to have some kind of build-and-forget road material, either self-healing or just really strong. Not today though.

[@IonizedComa]

Ancient romans: "See what they have to do to replicate a fraction of our power"

[@drewirvin5620]

I talked to a concrete expert at the engineering firm I work at. He told me this wasn’t new information lol

[@user-nn5yn4fv5m]

That's what I thought. Not sure why people are saying " just discovered" , because this stuff has been known for awhile.

[@brrjohnson8131]

Someone just said the other day this information is still unknown. I thought....did we lose the information again already?

[@tonybablony2041]

@@user-nn5yn4fv5minternet clicks is your answer

[@Goblinkatie]

The fact that they created an extremely hot endothermic reaction by using sea water and quicklime which creates a crystalline structure within the concrete (which heals itself from the expansion/contraction damage that all concrete experiences) whenever the quicklime gets wet, is what’s new. Your coworker is probably remembering the discovery of pozzolanic materials in the mix, which was a major breakthrough several years ago. My credentials: A professional building exterior expert (19 years in the industry) who is also a massive nerd. 🤓

[@charlesthomas135]

It's also not better

[@sneakyfox4651]

German WW2 concrete bunkers on the Danish west coast were so strongly cast that they couldn't be blown up with dynamite after the war. Nobody really knows why they became so strong, but it has been speculated that adding crushed flint may be the cause of the additional strength. Most of the bunkers are still scattered along the Jutland west coast, some decorated with cut-out steel plates resembling animal heads and tails of f.x. horses.

[@anadaere6861]

Combine the two and we should have Holy Roman Concrete lol

[@sneakyfox4651]

@@anadaere6861 Yeah. How about this slogan: We shall build this only once!

[@Biped]

Turns out that low buildings with 10 times the material strength they need last a really long time.

[@anadaere6861]

@@sneakyfox4651 The Thousand Year Build lmao

[@sneakyfox4651]

@@Biped Yeah, ancient Roman (concrete) structures were grossly over-engineered, and that helped them last so long. Modern structures use only the concrete amount necessary which makes them cheaper and faster to build.

[@charlieinabox1164]

It can’t hold the same amount of weight as modern concrete by quite a large margin. This is why ancient building had such large blocks.

[@JoostVanKommer]

I recently saw a video about how New York became the largest city in the US because they were able to use a new and stronger form of concrete to build the Erie Canal. This gave them access to the Midwest via water allowing them to become a major shipping port and grow in size. Otherwise Philadelphia may well be the largest city now due to their rail network at the time. They were trying to figure out how the Romans did it but couldn’t and used local limestone to build their own version. If only they knew at the time :)

[@BaseyCrown]

Might have missed the part where the compression strength is about 1/5 that of modern concrete. So the modern applications for this style of concrete are very limited, unsure it would be allowed to be used in anything beyond small private projects.

[@johnreinhardt9349]

@@feature.of.jarjar24 I think you misunderstand how important compressive strength is lol

[@kornelzsebe6989]

​@@johnreinhardt9349He misunderstood that the main point of concrete is the compressive strenght 😂

[@spamcan9208]

​@@feature.of.jarjar24yeah, they wouldn't have to be replaced every 30 years because they could never be built in the first place

[@terranovarain6570]

Roads Never seen potholes in concrete roads Because of cracks 😂😢

[@terranovarain6570]

I mean yeah not gonna build a skyscraper with it But they did make some pretty big buildings with it Pretty sure roads account for most wastefulness with concrete though

[@tanelehala6422]

Planned Obsolescence has entered the chat

[@kevinducharme1263]

nailed it. if they made stuff that outlasted the company, who would they get to buy their product?

[@nootnoot6404]

Planned obsolescence is trully an issue in hardware manufacturing. But in civil engineering, the 75-100 years life of concrete is due to the properties of the steel rebars we use. No matter how well protected the steel is, it's still going to be affected by either humidity or air, producing rust that will slowly degrade the surrounding concrete. Roman concrete was more durable because it didn't rely on steel. But the romans also didn't have to bear the loads and stress our modern concrete is supposed to hold. If you put roman concrete in a modern skyscrapper or on a highway, it would crumble in months

[@hermeticascetic]

you say planned obsolescence, i say that's keynesian economics in a nutshell

[@vinusuhas4978]

with corruption in politics

[@jessewest3523]

😫

[@brandonvacchio7614]

it’s so annoying to think that the whole reason it took so long to figure out the seawater thing was because, back then, it was just so universally understood among Roman engineers that you needed salt water for it to work, that none of the recipes specified “sea water”, it always just said “water”

[@danielkrcmar5395]

Modern concrete only degrades so quickly though because it's reinforced with steel that rusts and breaks apart the structure from the inside. Remove the steed and it lasts far, far longer.

[@kelvinle8662]

The only downside is you can't use rebar as the salt water will just rust the iron. But that seems like a possible fix. Edit: Since some people seem to be confused as to how steel rebar can corrode when encased in concrete - Concrete is never really "dry" (the water is still retained during the curing process). Steel needs oxygen to rust, and water has oxygen disolved in it (every fish in the ocean would be suffocating right now if that wasn't true). Cracks will eventually form in concrete, and although concrete made with salt water can self repair, the rebar will still be exposed to moisture and even more oxygen. In fact, salt water will accelerate the rusting due to the salt, specifically the chloride part of salt. But isn't NaCl its own chemical compound that has no properties of the elements that make it? Yes, but no, since the ionic bond between Na and Cl is broken when disolved.

[@cdntrooper3078]

True but with the concrete formed with sea water, the salts should dissolve with the acids of the quick lime. Meaning the re bar should be fine

[@stonewalljackson2734]

Galvanized rebar?

[@kelvinle8662]

@@stonewalljackson2734 that will slow down the process but the steel will eventually rust when the zinc coating deteriorates.

[@NoIwont]

One adds water, whether it's salt water or fresh water to make concrete...your precious rebar won't rot within.

[@smh9902]

Use basalt rebar or fiberglass rebar. Done.

[@Master_Of_The_Void]

Roman concrete: repairs itself A 2 ton heavy machine going over it every few seconds:

[@notoriousbig3k]

And still auto repairs

[@RadekZielinski.]

More like 50t if it’s a lorry. Cars and vans weigh around 0.5-4t. Either way they still have to pour tarmac and they come with holes if you like it or not. Structurally modern structures should last a lot longer anyway than his 50 years as we have rebar, something romans didn’t have.

[@Mwuff7775]

Do you think they built roads to not use them? Marching massive armies, horses, carts, etc over them isn't use? Do you drive heavy machinery over concrete buildings?

[@Saddutchman]

This stuff isn't suited for roads unless you enjoy aquaplaning.

[@n00b1n8R]

​@@Mwuff7775 concrete roads are everywhere mate

[@lukeuehling3794]

I like the makeover you gave your channel. I think it still has some high spots you have to level out, but other than that, it’s looking smooth and I appreciate your effort by improving our viewer experience.

[@gabrielthompson3853]

If you add graphene at .1% of the total mass of concrete it increases its structural integrity by 30%. You can obtain this graphene by electrifying tires eliminating a massive amount of waste for about $100 per ton of tire. It’s a perfect cycle that’s affordable to drastically in improve our roads and bridges. You can look those numbers up too.

[@Aquaopifex]

Unfortunately Saltwater doesn't mix with steel very well. Romans might not have to worry about that but rebar is very important for modern construction. Making modern construction without rebar is not very practical and therefore having saltwater present is not going to work for new construction. Also on the topic of Roman construction lasting so long, there is a very heavy survivor biase involved there. It was much harder to estimate engineering margins of safety so some construction fell apart and some lasted much longer than planned. We also tend not to try to make structures that last into eternity now for a variety of reasons. It is absolutely fascinating to see the history of engineering though and I am very glad we have this insight into this piece of the puzzle. Thanks for making another great video

[@icarusbinns3156]

Yes… but sidewalks. That’s all I gotta say

[@angrypastabrewing]

Maybe rebar is no longer necessary because of quicklame

[@Aquaopifex]

@@angrypastabrewing So the reason we use rebar is because it allows concrete to withstand tensile loads (pulling apart). Without rebar, concrete can only withstand compressive loads (pushing together) and it is really good at that. The Roman structures were made with designs that had to be very inefficient because it could only handle compressed loads. If you look at the Pantheon, it is absolutely huge compared to the internal volume. That is because there needs to be a complex series of arches to maintain compression throughout the structure as it distributes the load outward. It is a marvel of engineering and very interesting but a bad way to make a modern building. I recommend watching Stephen Resslers great courses video series "Understanding Greek and Roman Technology" if you want to learn more about historic construction and how buildings need to be constructed without rebar. Quicklime and the "self healing" properties don't solve the core problem of being unable to handle tension.

[@Aquaopifex]

@@icarusbinns3156 Sidewalks don't use rebar which would make it more relevant but also this is meant to be relevant for repairing small cracks. Sidewalks typically fail because the supporting ground has moved. If that happens the difference between .3 mm of healing and .6 as suggested in the article is not going to be enough in almost all cases. If the ground underneath is no longer flat it will crack with or without this technology

[@icarusbinns3156]

@@Aquaopifex you’re attempting to make this point to someone who lives in an area massively affected by shrink-swell soil. But all the arguments kept going back to rebar, making it sound like rebar is used in everything, when it isn’t. Like sidewalks! If the roman cement mix is used in sidewalks, it would cut down on repair time and repair projects

[@homelesseevee4310]

As a new yorker... we need this

[@NoIwont]

as a New Yorker, you needed that 200+ years ago...same with my town.

[@Subreon]

Why are you homeless eevee QnQ

[@lilnutt5580]

absolutely love the pfp and name

[@r1hgaming]

as a Californian.. we need this

[@skeletonsinyourcloset]

THE ENTIRE USA NEEDS IT, THAT CHICAGO LOOP NOT LOOPIN AN THE 405 AINT FIVE'N

[@johnmansell5097]

Sodium salts can’t be used with untreated rebar as it rots them, secondly NaCl increases early strength but slows down the strengths at 28 days. From my ancient memory Roman concrete was quite slow in hardening compared to current concretes.

[@user-jw9kl4qd9t]

FYI: One of the secrets of the great wall of China is that they mixed rice flour into the mortar between the stone blocks. It also had self healing properties.

[@drunvert]

What's funny is that in 1976 I did a science experiment for the science fair on making three different concrete blocks and testing the strength. Seawater, tap water, distilled water.. My hypothesis was that distilled water would be the strongest, but I found that seawater was noticeably stronger.. I got second place.

[@gaztellprime]

Was first place a baking soda volcano? Edit: It's only been a week so wasn't expecting much and forgot it afterward, but I was expecting a Phineas and Ferb reference from my comment.

[@DarkMatterX1]

​@@gaztellprime Always. It was also the Principal's nephew.

[@drunvert]

@@gaztellprime No but I did that for a class project

[@somewhat1007]

I was taught (in college) that the presence of salt in concrete makes it weaker and causes efflorescence

[@mrman1536]

​@@somewhat1007salt damp isn't much fun either.

[@YourCapyBruv_do_u_rmbr_3Dpipes]

Whoever came up with self-healing ancient concrete was a serious galaxy brain

[@markusgarvey]

The secret ingredient was hemp.

[@andrewheagwood5950]

​@@markusgarvey or mooshrooms

[@val.6724]

​@@MrBooblo086 It was most definitely not by chance. You seriously underestimate the prosperity and wisdom of ancient civilizations. Maybe watch some documentaries about it.

[@stephenodubhlaoich]

​@@MrBooblo086 Who knows..Eratosthenes, a Greek, calculated the circumference of the Earth using some measuring sticks, 800 kilometers, and studying the moving shadows cast under the sun

[@YourCapyBruv_do_u_rmbr_3Dpipes]

@@stephenodubhlaoich yeah fr.... And then for many 100s of years during the long middle ages in europe and who knows where else many continued to believe the earth was flat. Those silly rubes. Some of the ancients were serious chad brains.

[@TookAHikeNowWhat]

For-profit construction companies: "Oh ha ha, ya, ok, ha ha... ya... ha very nice, ok... Gee whiz look at that"

[@atomblack2093]

Did some research on this awhile back. It’s super interesting looking at how we built back then. Much of the architecture was built with very clever and precise masonry, but I was unable to find good descriptions of what kinds of concrete forms were used. I assume timbers and rope. Couldn’t find a source, but I got to thinking that in order to make the iconic Roman pillars, that the vertical motif was caused by the nature of strapping the timber forms in place, and later carved to uniformity.

[@RamblinPhoenix]

In slight defense of modern concrete: It is infact 10 time stronger than the Roman stuff. So, a modern concrete bunker can take a rocket better than a bunker made of ancient stuff. But in 50-100 years the modern stuff will have degraded and the Roman stuff is still there.

[@bernier42]

Unless we shoot rockets at the Roman stuff

[@cyancyborg1477]

​@@bernier42 Hey you wanna?

[@kintamas4425]

We probably don’t need the durability to take a rocket for the roads.

[@cyancyborg1477]

@@kintamas4425 No no I wanna see something.

[@Loj84]

@@kintamas4425 but it may have a problem with fully loaded semi trucks driving over it 24/7. I don’t know the actual numbers though, so maybe it doesn’t matter.

[@user-pc7kt6kb3p]

I also heard that part of the process is to mix the quicklime chunks with volcanic ash and the other components of the mix, dry-roast it and only then add the seawater. The chunks of quicklime would be activated, but can't completelly react with the water, because of the size of the chunks, leaving enough leftover to react whenever the concrete needs to heal itself down the line.

[@cristiewentz8586]

Must be an alien recipe. We KNOW that ancient man couldnt figure it out 😂🎉

[@omranhashim1028]

⁠@@cristiewentz8586 How do you KNOW that lol Not sure if you’re being sarcastic

[@cristiewentz8586]

@@omranhashim1028 sorry. Tried to make the sarcasm very broad. I know too many believe that ancient man= less smart than us modern hoomans.

[@omranhashim1028]

@@cristiewentz8586 ah I’m glad it was sarcasm. Sorry for missing it but as you obviously know there’s plenty who think we’re smarter than our ancestors because of the technology we have. The funny thing is the vast majority of us didn’t contributed to the knowledge or inventions, we just happened to be born in this age. Whoop-de-do what an accomplishment lol

[@Hi-vd8lr]

Most likely they stumbled upon that due to an inability to get a method to crush the lime fully efficiently

[@Celibrimbor]

Unforunately theres too many companies making too much money from the current versions to want to change to a more lasting version

[@hellstromcarbunkle8857]

Also, don't forget that Roman concrete was based not on sand but on volcanic fly ash, rich in alumina. When alkalized, the minerals cross link on the silicon-aluminum metals, creating an actual polymolecular bond.

[@JoeySedik]

you should also mention that using sea water nowadays is prohibited due to the rebar introduced in the structures.

[@allowmi]

You wouldn't need rebar if the roman recipe is as good as they say... Or there's glass fiber, or some composit/polymer etc.,

[@footpac]

And like, sidewalks lmao

[@itstheweirdguy]

He's a clickbait artist, of course we have better technology now and nothing was better with their concrete thousands of years ago. Total total BS

[@krawc0]

​@@itstheweirdguyHow do you explain all those ancient roman constructions that are still standing today in pretty good condition vs anything modern and abandoned is crumbling to dust?

[@tobyhouston9939]

@@itstheweirdguyone takes loads better and the other lasts longer. Its like have one or the other

[@chairde]

The Roman’s were genius level engineers.

[@wlfrndz8743]

they were ahead of their time in many regards

[@stever3425]

​@@wlfrndz8743Apparently, they were even ahead of our time.

[@santouchesantouche2873]

​@hiooxkrmagkis9323 one of!? Wowwwwwww. One! A solitary person. One, the loneliest number... I suppose the exception proves the rule in this case and this case only.

[@jmac6055]

@hiooxkrmagkis9323 This comment was about their genius level engineering. Not a singular middle eastern architect. Roman engineering catapulted Europe into the future.

[@knova7597]

Not entirely, they had steam engine components that they never figured out how to use.

[@iSaac-kp5lk]

Ancient people really knew the "how" but struggled with the "why"... we however know the "why" which leads us to the "how" but sometimes when there isn't a "why" to get us started, we struggle with the "how".

[@410cultivar]

It was never a secret, concrete manufacturers are well aware of this. The issue is size. After so big you need rebar. Rebar gets destroyed to quickly when using the ancient mix