Tangentially related to this, one of my hobbies is to explore old long abandoned ghost towns and mining camps in the Southwest US. It is really impressive how well many of these structures have held up in harsh climates. One of my favorite parts is seeing how repairs were improvised in the wilderness using whatever supplies happened to be available.
The standard approach to trash back then was to throw it in a pile nearby. Picking through those dumps can be really fascinating and a surprising amount of items are still in good shape. A simple heuristic for how old a glass bottle is is how thick it is. A modern beer bottle looks paper thin compared to one a century old.
Looking at old structures and tools really makes vivid how disposable many modern items are.
Depends on the material I'd say. Large temperature swings like common in the desert certainly don't help. Wind/sand abrasion could also be an issue. But in general you're right, desert climates can be good for preserving things. The only thing better would probably be a permanent ice cover.
If they are under cover away from UV and heat, they can be well preserved. Modern material tend to degrade in Phoenix sun, and 110° and sometimes 120° summer days.
Same thought. Where I grew up...if water didn't kill it, tornados would. The only barns that stood the test of time were made from the now nearly extinct chestnut. They turn grey and get knotty and twisty as they age but are nearly indestructible. Everything else rots away in the humidity.
One rather interesting memory...I remember my father rebuilding an old barnish structure with railroad ties for the frame. Apparently they soak those suckers in tar...out in the sun each day they'd start sweating some black tar stuff again that's nearly impossible to get off your hands. Those haven't aged a day in 20ish years. Makes me curious why more structural wood isn't treated this way.
I think this is one of the saddest aspects of the progression of our current expression of Civilization as we forge through time:
The lost knowledge and, even more importantly, the fundamental resource depletion/extinction caused by our activities which result in both the knowledge of *how* to do/accomplish/build/mend/heal, as well as the actual natural resources required to execute that knowledge in a meaningful or impactful way on your life...
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However the Chestnut appears to be largely wiped out by two separate blights
Correct. They've had some success crossbreeding them with a Chinese variant, but the jury is seemingly still out if they'll actually repopulate and how good the wood will be. The wood from American Chestnuts is legendary, and I can personally attest to that. So much so that old barnwood can be sold for good money. Shame nothing else has replaced it properly.
So I had some experience similar to this with an awful substance called cosmoline. Russians used it to store old guns, and they did the same thing really by sweating some chemical every time they heat up.
After some reading and thinking, I decided just to bake the thing at 250. It sweated tons of that awful red jelly out, then never again.
Don't get me wrong, I'm definitely not for polluting the groundwater, but seems it can be mitigated with proper heat treating prior.
Well, the idea is to just heat them past any temperature they'd experience naturally such that they don't bleed anymore. The wood itself would still be saturated in awful chemicals.
For railroad ties specifically, I imagine it would be deemed way too much cost. But for say, house framing lumber... guaranteed termite free forever, I think people would pay for it.
Usually, tar-like substances still sweat out a range of volatile aromatic compounds which aren't good for your health. Yes, heat-treating them would get rid of 99% or more, but that's not good enough for housing.
As someone that does swing dancing and with quite a lot of people into vintage stuff there has been this talk of "survivor" bias whenever we talk about how stuff was made better back then.
Naturally the cheap stuff didn't tend to even remotely make it this far.
Curious what your opinion is as I haven't heard much about tools etc.
The transition to "everything plastic" definitely was a big jump in term of quality in general. If you look at cameras from example, "cheap" old (pre 1960s) cameras were just as reliable as expensive ones, if not more, they were just simpler in design and built with less tolerance. When they started building consumer grade cameras in the 80s they almost exclusively used cheap plastic and cheap electronics which inevitably die (LCD screens instead of mechanical displays, undersized rewind motors instead of manual advance levers, autofocus vs manual focus, &c.).
The transition from hand built to machine built and the general miniaturisation of most mechanical/electronic systems since the 80s also means it gets harder and harder to fix. I do believe stuff was made better in term of repairability and simplicity, simply because they didn't have any other ways.
That's why you can pick up virtually any pre 1960 camera and repair it but cameras from the late 80s early 90s are incredibly finicky. I just picked up a camera from 1950, opened it, cleaned its lens elements / shutter mechanism and it works just as good as when it came out of the factory. It took me an hour and two screw drivers to go from "unusable paperweight" to "fully functional", the most advanced pieces of machinery in there are metal gears and springs.
There are a couple factors that would result in a longer lasting tool of Yore...
There were no plastics and other ephemeral materials, and so tool handles were wood, leather or metal.
There was no 'mass production at global scale' - effectively every tool was hand made, or made by machines that were made by hand to make the tools -- and all of which were done without aid of computational mathematical prowess-by-proxy...
So, smaller batches of potentially longer lasting product because everything was continually being crafted by hand and observed by human eye...
In terms of building I remember hearing how in the distant past (anything before the last 200 years or so) the buildings that survived to this day have just used way too much materials in a way that would seen as wasteful today (e.g. double as much stone as was needed because they couldn't calculate it as precisely as we can today).
Would you be willing to pay double for your new home to make it last 300 years instead of 100?
When answering that question, note how much effort is needed to retrofit to modern needs. Electric, running water, closets, all things modern humans demand that you would need to retrofit.
My great-great grandfather argued this exact point to my dad in the late '50s: the buildings in Switzerland (and, later, Indiana) that "stood the test of time" were built to a different (far more expensive) standard.
I think modern day goods are better at being just durable enough to serve their intended lifetime, but no more than that.
Also, I think every generation has products that last a really long time. My personal example is that 30 years ago I saved up my allowance to buy a casio keyboard, which after a few years moved into an unheated attic, and then some more years after that to a cold and damp basement. Recently I dug it up out of the basement, wiped off a thick layer of gunk, put in a fresh set of batteries, and aside from one status led not working it works as well as the day I bought it, and even the plastic hasn’t discolored much.
I don't see how you can call the climate "harsh" with a straight face since it never rarely get moist enough for long enough for water and bacteria to do much to wood and masonry.
There's a reason you pretty much never see 100yr old unmaintained wood and masonry structures in New England, midwest, the PNW, etc.
> I don't see how you can call the climate "harsh" with a straight face since it never rarely get moist enough for long enough for water and bacteria to do much to wood and masonry.
Most modern products/methods/coatings deteriorate very quickly in the extreme temperature swings of the desert. If they're exposed to the sunlight, most things can't handle the UV in combination with the extreme temperatures.
I own a desert property and do a lot of DIY construction/maintenance. To argue it's not harsh is extremely uninformed.
Minnesota routinely sees 90 days in summer and -20 days winter. Water plus 110 degree temperature swings destroys a lot of things quickly. Plus vegetation, mold, animals
I never said nowhere else is harsh, I just strongly object to arguing the desert is not a harsh environment.
My parents are in the midwest which is where I lived into my 20s, and my dad did a lot of DIY maintenance on their house which I helped with. There was no comparison in terms of how quickly things deteriorated there vs. here in the Mojave where I have property. The "15-year" Behr brand exterior paint I put on a refinished shed ~2 years ago is already cracking and peeling off, simply because the substrate undergoes such extreme thermal expansion and contraction daily between the day-night cycle, with the UV quickly embrittling the skin.
The main problem we had back in IL was ice-heaving of roads and patios/sidewalks. But asphalt-shingled roofs easily lasted over a decade, barring some exceptional tornado-style event ripping them apart. Asphalt shingles quickly become embrittled in the desert, and the frequent gale-force winds break them off. It's why you find Terracotta/slate/metal roofs so common in the desert; the environment is too harsh for the cheaper asphalt shingle stuff you find across the country.
And it's not like deserts don't get freezing temps or snowfall. My last camping trip in Joshua Tree National Park concluded with my tent collapsing on me under a snow load.
Airlines and the military parks aircraft in the desert for storage because with a little bit of prep work at the beginning the aircraft will stay in good shape. Constant rain would be far worse.
The thing is desert structures still have to deal with water ingress.
It does rain, and when it rains it's often a blowy monsoon of doom, assaulting desiccated wood structures which more often than not have developed some leaks from the year-round wind/sandstorm/thermal/UV abuse and complacency promoted by deceptively always-dry conditions.
And when lumber that has been dry and 120F+ for half a year abruptly gets soaked in water, its dimensions quickly change in non-uniform ways; it twists, bends, splits, and softens. If any of this moistened wood juice finds its way down into the ground, subterranean termites discover the food source in a veritable food desert. I think you can guess what follows.
Every climate brings its own challenges, of course, but it still seems true that that's better than dealing with constant precipitation, freezing, and so on.
If we're talking about the PNW, it doesn't take a genius to look around and see nature alone manages to build towering long-lasting structures in that environment. Some of those redwood trees are older than the oldest buildings in the entire nation.
The desert's evolved long-lasting structures are shrub-sized and endure by retreating underground. Otherwise there's rocks.
>>nature alone manages to build towering long-lasting structures in that environment. Some of those redwood trees are older than the oldest buildings in the entire nation.
Yes, and they are continuously maintained by the living tree's processes, building everything from new roots, bark, branches and leaves. The question you need to ask is how long a dead redwood stays standing in the Pacific Northwest? What is the proportion of standing live to standing dead trees? How long does a fallen redwood trunk last, even starting out 20 feet thick?
>>The desert's evolved long-lasting structures are shrub-sized and endure by retreating underground
Yup, due to the same processes - the high heat and low humidity make very large transpiration loads, evaporating water very rapidly from the leaves, so tall structures with huge capillary capacity are unsustainable. It isn't because they wear out fast from the wind.
You seem to be mistaking attributes of biological growth processes for attributes of mechanical wear processes.
We can see the difference weather makes in the case of Cleopatra’s Needle, which in its short stay in New York has seen some weathering it avoided for thousands of years in Egypt.
The desert is very harsh for life, but much more gentle on structures. Even when it does rain the arid environment evaporates it away quickly.
It's not even a close comparison, you find structures from the 1960s in the southeast that are far more deteriorated than ones from the 1860s in the southwest.
Are there really sites undisturbed enough for you to see how they did repairs or disposed of their trash? That sounds amazing.
SW-America is definitely on my bucket list and I love ghost towns. In Western Europe it's hard to find any abandoned place older than a couple of years that's preserved well. I guess it's because the next city is never very far and there's always uncultured idiots whose idea of fun it is to vandalize places for no reason.
You’re in for a treat, it’s within a timescale of 200 years or so, but definitely. The climate, terrain, distances, ownership, and uselessness of most of the land involved really encourage preservation, albeit rotted out and rusting.
It's incredible what's been left behind and still in decent shape. As you've found, any place with a lot of human traffic tends to get destroyed by vandals but fortunately the SW deserts are massive and hold a shocking amount of old mining roads that lead to well preserved locations. A spot that requires a modest amount of effort to reach tends to filter out the idiots.
Another favorite site I didn't mention are the old mining structures. Image search for something like "old mining headframe" to see the sort of thing I'm talking about. There are a lot of those structures still standing from many decades ago.
This does even change vintage car prices, certain places out west (Arizona, Utah etc) vintage cars typically are less rare (and therefore cost less generally.) Whereas snow, the salt used to treat roads and rain will wreak havoc on the frames and bodies in other areas.
Which is just a scapegoat problem, shifting the mind away from the original problem - disposable containers creating large amounts of waste that mostly end up in landfills, or worse, scattered in nature.
The energy use of washing bottles was never a concern. The energy use of transporting heavy bottles was largely offset by globalizing beverage production.
In Sweden we sort them by colored or translucent, they'll be smashed and reheated to be made into brand new bottles. Haven't seen used bottles in quite awhile, not sure if it's good or bad.
Germany has a bottle return scheme. It's common for your (glass) bottle of beer or sparkling water to have significant wear marks where it's been rubbing against neighbours in a crate.
We used to have it as well, I remember from when I was a kid. It says on Wikipedia that we replaced the glass bottles with PET mostly. So I guess we have the same scheme, but not on the same scale anymore (one bottle supposedly gets reused 40 times on average).
Though the rare ones I get I just throw in the glass recycling that'll be crushed, made into new bottles and insulation material.
I was collecting some bottles and after trying 5 grocery stores who all told me they don't accept bottle returns (happy to collect the "deposit fee" though!) I gave up and threw them away in the regular recycling bin.
It may also be down to better sugar/carb content and fermentation control, and/or better temperature control during storage. If yeast remains active in the bottle, the CO2 buildup causes overly high internal pressure, as could high temperature - so either the top blows off or the bottle becomes a glass grenade.
It's struck me, reading roman authors, that they were considerably more obsessed with building a legacy than we are. Not just getting powerful or famous in life, but entering the history books, to become big name like Scipio Africanus.
May be that it comes with living in an "eternal" city that's been the same as long as anyone can remember, with generations coming and going and most human activity washed away like sand castles on the shores of oblivion. Making some form of lasting mark seems almost urgent when you look at it from that perspective.
Hard to know if their culture was different, it could easily be a case of survival bias. Those obsessed with creating a legacy for themselves were more likely to create a legacy that lasted.
Think about all your contemporaries, unless they're incredibly famous their story will be lost in time.
I read on here - and I hope someone can find the link because I just spent 20 minutes looking for it and now I can't find it - an economist or similar academic grousing about a rail bridge in the UK that had been upgraded for the first time in an [arbitrarily long amount of time] to support heavier trains. The complaint was that, surely, a bridge should not last that long without needing an upgrade; you should build a cheaper bridge and replace it, because whatever gains you can make from investing the difference will outpace the replacement cost.
I guess the point is that building a legacy of infrastructure is, generally, not economical and therefore should be foregone in favor of building a legacy of financial holdings.
Rome wasn’t very old by the standards of 1 AD. Elsewhere in Greece, Egypt and Middle East, cities had been inhabited for several millennia.
But Rome’s founding just 750 years earlier was mythological because the place was too remote to even have written history until much later. Virgil had to invent a Trojan connection to elevate the national epic.
Being obsessed with building a legacy is not so uncommon. Machiavelli comes into my mind, for whom future fame is one of the most important motivations for rulers. Or think of Pericles, who states in his famous Funeral Oration: "there are mighty monuments of our power which will make us the wonder of this and of succeeding ages".[1]
Renaissance writers like Machiavelli were very influenced by the romans, to the point where some were even into Roman LARPing: Wearing togas, refusing to speak vernacular, etc.
Maybe there's survivorship bias in that sample. Are ancient authors we still read more likely to be obsessed with legacy-building than the ones we've forgotten?
Capitalism has no legacy. After all, time preference can't be negative. Implying that destroying the earth is a perfectly viable idea because the discounted future value of earth is $0 to many people after their death.
A time preference of 0 is equivalent to never consuming (e.g. never consuming the earth in its entirety).
Did the Romans really know that using certain volcanic rocks would make their concrete structures last longer? Or did they mostly just use whatever aggregate was convenient and the structures that have survived are the ones that used the right rocks? The latter sounds more plausible to me.
Of course we can still learn valuable lessons from these surviving structures.
They famously shipped the right kind of volcanic ash to e.g. Spain rather than using local materials. They didn't know the chemistry for why (otherwise they could have found the materials with the right characteristics locally), but they definitely knew that particular aggregates lasted better than others.
> Did the Romans really know that using certain volcanic rocks would make their concrete structures last longer? Or did they mostly just use whatever aggregate was convenient and the structures that have survived are the ones that used the right rocks?
Why not both? How do you think you discover that certain things work better than others?
Humans are clever in any time.
For example, the Pantheon has a very specific profile (thick at bottom to much thinner at center of rise) to the dome in order to allow unreinforced concrete to be used. That's a case of very deliberate design.
Pompeii is in a highly volcanic area. So, digging is difficult and expensive. This put a wrench in the standard formula for Roman building. So, instead, they elevated everything slightly. That's on the spot ingenuity and convenience.
Finally, there is a survivorship bias--structures specifically built with longevity and durability in mind and maintained by people are the ones that survived.
The Colosseum was also built with lead rebar for earthquake resistance. And that lead rebar was extracted and stolen over the years because the lead was valuable.
Taking the rebar out of a building tends to make it a touch less durable.
It is very interesting. Certainly there are holes where people have stolen iron. But more importantly, the materials in the Colosseum are massively pillaged by christians for use in other buildings.
The Pantheon was turned into a church, and thus was off limits. In Rome they call it "recycling".
The Pantheon was not completely off limits. Pope Urban VIII. (Maffeo Barberini, pontificat 1623-1644) had the bronze cladding of the Pantheon taken down to have 80 canons cast from it. He has had a cover-up story spread that the bronze was used for St. Peter's Basilica.
Jonathan Blow makes a bunch of great points about our simplified view of ancient people, versus the reality of their complex achievements which could only be brought about by lots of ingenuity and iterations.
He started off well with the history of civilization collapse but then he got the heart of his presentation with the misguided idea that modern software is more broken recently. He showed some incomprehensible bugs in Visual Studio.
All I have to say is that on Windows the Blue Screen of Death was a prominent problem for many years. On the original MacOS that was non-preemptive multitasking and no memory hardware protection, any program could cause a denial of service or take down the whole computer. These are 30 year old technologies that were clearly worse in many ways than modern equivalents.
Has software improved recently? No, I would say it has gotten somewhat worse recently but if you look at where we are today versus say 1998, things are clearly better. It isn't really possible to know if we are in a major decline or a minor local minimum.
I think software will never feel like it's improved because as technology improves and changes, new features will be expected of software and so while some parts of software improve, other new parts will bring down the average quality.
It reminds me of Shepard Tones which sound like they are infinitely increasing in pitch which is impossible because the human ear can only hear certain frequencies. (https://www.youtube.com/watch?v=BzNzgsAE4F0)
Microsoft is not a legitimate standard of comparison.
Their business model was (and to a degree still is) predicated on getting people used to everything having bugs, and not complaining or, more importantly, returning it for a refund, angrily. They succeeded beyond their wildest dreams, and now everything else works almost as badly.
The BSOD is kind of actually the opposite in reality. The software is worse, the hardware is better, so we are running more software to containerize those bugs. Software is more buggy and bloated than in the past it's just that the failures are silent and we don't have to reboot the entire system we just reboot pieces.
win 9x was absolutely worse and a lot less stable than the NT lineage (that we're currently in). classic macos was absolutely worse and less stable than the NeXTSTEP lineage we're currently in. I used linux for the first time in 1998 with Red Hat 5.2 and it was an absolute pain to get working/install and a lot of hardware was unsupported. At least it didn't crash as much as windows 9x!
Even for reasons other than Rome's history, this is one of the best talks I've ever seen. IMO every software engineer should watch it and I recommend it to colleagues all the time.
The lack of writing probably impaired things greatly. I know the Romans had writing. But did they ever write manuals? It was not like Gutenberg's printing press, which put progress on a steep upward trend.
Not sure what you have in mind with "manuals", but I believe there were treatises on every subject, e.g. Vitruvius' On architecture (~20BC), "a guide for building projects. As the only treatise on architecture to survive from antiquity, it has been regarded since the Renaissance as the first book on architectural theory, as well as a major source on the canon of classical architecture. It contains a variety of information on Greek and Roman buildings, as well as prescriptions for the planning and design of military camps, cities, and structures both large (aqueducts, buildings, baths, harbours) and small (machines, measuring devices, instruments)"
Ptolemy (100-170AD) wrote treatises on many subjects, and his works on astronomy and geography "never ceased to be copied or commented upon, both in Late Antiquity and in the Middle Ages" https://en.wikipedia.org/wiki/Ptolemy
Vegetius wrote a military manual On military matters, extremely influential until about 1500.
(So much ancient writing hasn't survived, e.g. none of Aristotle's many writings survived - what we know as his writings are just his students' lecture notes.)
The fact that any books would have to be copied by hand would disastrously limit their spread and influence. How many people could learn calculus if only 5 copies of the textbook were created?
So many being lost is an inevitable consequence of very very few copies ever existing.
Using volcanic rock in concrete was done to lighten vaults and domes, e.g. the Pantheon. This is distinct from using volcanic ash in the concrete mix which was essential for the long lasting strength.
Arguably Roman concrete was discovered by accident when someone mixed a batch of lime plaster using the volcanic ash around Pozzuoli instead of regular sand.
In fact it was, but on the second day, it would no longer compile. After a long debugging session, Romulus realized Remus had unpublished the hWall (or aMoenia) function in the night. Romulus then murdered his brother.
It’s not just the monuments. Everywhere you go in Rome there are fountains with cold, clean drinkable water. The combination of the roads, rivers, infrastructure, and monuments leaves you feeling like we kind of aimed a little low, at times.
They're not the same fountains, nor the same water grid (through the modern grid might use portions of the Roman one). There were centuries where Rome was completely abandoned and reduced to a collection of villages and feudal holdings. They used wells for water access.
Super interesting, ok I think I just assumed otherwise but thanks for the explanation.
One follow up though, did ancient Romans have fountains? Maybe not the same ones that exist today, but more or less did they, ancient Romans, have these public water services as well?
Yes. “For more than two thousand years fountains have provided drinking water and decorated the piazzas of Rome. During the Roman Empire, in 98 AD, according to Sextus Julius Frontinus, the Roman consul who was named curator aquarum or guardian of the water of the city, Rome had nine aqueducts which fed 39 monumental fountains and 591 public basins, not counting the water supplied to the Imperial household, baths and owners of private villas. Each of the major fountains was connected to two different aqueducts, in case one was shut down for service.” -Wikipedia.
One other explanation is that many of these monuments didn't stand around undisturbed for 2,000 years, a lot of work of hundreds of generations of humans went into these monuments.
The Porta Nigra is a great example - it's an ancient Roman city gate in Trier, Germany, still standing since it was built in 170 AD. The ground floor was buried for a long time (>800 years?) preserving it. The gate was a ruin for a few hundred years, around 1000 AD a church was built around the gate keeping the construction in place. As part of a general de-'churchification' 1802 Napoleon had the church-part taken off and had the gate and its insides fixed up (while the ground floor was still buried!).
So the gate didn't have to survive on its own.
Native speaker (Brit in USA) here. Either one is fine, although they have subtle differences in meaning and implication (to me) in this context.
The first thing that struck me before I gave this any real thought is that "How" here connotes a little incredulity or even amazement (to me). There's an implied, rhetorical sense of unlikelihood of the fact. ("How are Rome's monuments still standing?! Shouldn't they have fallen down by now?")
"How" also implies (to me) that we seek an explanation of processes, means, techniques, or methods. It invites an answer that's somehow more dynamic and more detailed. "Why" is asking "for what reason(s)?" The "Why" version of the question feels more direct, but the answer space is broader and more abstract. "How" feels, forgive me, more concrete here than "Why" :)
How -> explain the processes, techniques, or workings. Why -> explain the reasons/causes. Obviously, there's overlap there, and the distinction is subtle, so perhaps some of this is only in my head :)
How and why sound to me like slightly different questions and the best one might depend on the answer.
"Why is something still standing" could be circumstances related - eg all the other ones got demolished except this one for reason x, or y group of people stepped in to maintain it etc
"How is something still standing" sounds more like the method for it standing - eg the structure had some extra cross bracing on the lower level etc
one very impressive feat is the Pont du Gard, this thing has been in disuse for 1500 years, and lots of stones have been looted over the centuries. And its aspect ratio is somewhat thin.
How many of these have undergone serious repairs? I've seen multiple news stories about colosseum repairs and renovations during my lifetime, and I'm sure there were plenty of earlier efforts. Rome has burned or been hit by major earthquakes multiple times since these things were built.
I’m currently wrapping up a trip touring many ancient monuments during winter (aka off-season), and nearly all of them were having some kind of renovation work being done. Usually it’s a combination of whatever ancient stone is left from antiquity, combined with new material of the same type that would have been used originally (though not in all cases, there is some form of “artificial stone” that is used at times, not sure of what that is).
So, my guess at the answer to your question would be all of them, many times over.
I saw an article a while back about the unique properties of ancient Roman cement. It seems that the sea water hitting the walls created a rare mineral when due to a chemical reaction.
I often wonder about how things are built without preservation/archival in mind. We live in an age where so many things are built in so much faster than the past but, with the expectation that they will be replaced even faster than in the past.
The Romans had no arabic numerals and no arithmetic - that's why the statics of the buildings were not calculated. So some were over- and others under-dimensioned.
You only see the over-dimensioned ones. They are still standing today.
> Roman concrete, on the other hand, is a simpler mix of quicklime made from baking and crushing limestone rocks and, most importantly, volcanic rock aggregates of various types, which were abundant in the region surrounding Rome. In contrast to the aggregates used in modern concrete, these volcanic materials used by the Romans are highly reactive and the resulting concrete remains chemically active for centuries after it first hardens.
By the way, I don't buy this entirely. Let me tell you why.
The Pantheon is mostly stones and bricks, and "some" concrete to keep the bricks together. These large stones are held together by simple force of gravity, very much like the Pyramids in Egypt (~4,000 years old, or double the age of the Colosseum or the Pantheon).
I'm not a materials engineer (just a software engineer). Can someone with more knowledge comment on my view?
We use reinforced concrete, concrete with steel bars inside. This allows us to built really thin and strong concrete bridges, balconies, roofs, etc.
But the steel rusts after a couple of decades.
Rusted steel is marginally larger than new steel.
So when the steel bars expand by rusting, it pushes against the concrete from the inside, causing cracks. Then lots of water can get in it rusts faster.
Eventually chunks of concrete fall off and structural collapse follows.
If we built like the Romans, it would be more expensive, but would last 1k+ years.
Plastic coated rebar is a product. In theory it can solve the rusting problem, but in practice the coating will get some nicks during installation that can concentrate corrosion leading to point weaknesses. There are additional concerns with the bonding between the concrete and the coated bar.
Steel and concrete have similar coefficients of expansion. Most other choices don't and so as temperature changes something has to bend or give which reduces life.
epoxy coated rebar=1.1-1.3 <- terrible in practice
zinc coated rebar=1.2-1.4 <- good
stainless steel rebar=3-4-5 <- very, very good
carbon fiber rebar=? <- AFAIK not used in new buildings, as it has a series of issues in practice, used in some rare cases of consolidation/repair of old buildings, mostly not as rebar but rather as mesh/net.
What is used, not as "main" reinforcement but to have a (much better) mass strength are fibers, they can be either steel or plastic.
I think I do not understand the numbers. You wrote "costs/duration" so higher the number the worse solution (bigger costs or worse durability), yet the descriptions suggests otherwise.
Sorry, numbers are cost only (1 is "normal" rebar steel) order and text are duration ("normal" steel no text, base duration, the terrible in practice means that it doesn't offer longer duration, and may have issues in adherence to concrete).
Not so surprisingly the higher the cost the longer the duration.
There are stainless steel rebar and epoxy coated rebar for structures exposed to the elements. Stainless steel rebar appears to be kind of expensive so its use is limited.
Or, is there any promising technology that allows to use steel bars that have some space inside, so that when they rust, they don't break the concrete?
I think we’re missing another key factor here. Most “well preserved” buildings are ones that are in continuous use. So they get maintained and repaired. A temple in south India is about a 1000 years old. It has seen repeated damages - some intentional during conquests - but survives to this day because the damages were patched up within a few decades. The “few decades” it can go - even with damages - is likely from the material and construction. But the centuries that add up comes from regular maintenance.
Well, while this is true, there is some level of survivorship bias here. Plenty of comparable South Indian temples were torn down, and the ones that survive are mostly quirks of chance. Even the ones that do survive have seen many of their gopurams (monumental gates) collapse after a few centuries due to political apathy in modern times - the one I recall most recently was at Srikalahasti.
It is both..... so both the author and you are correct.
Modern concrete has rebar, which eventually gets rusted, and corroded, and fails (in 150-200 years). Also, roman concrete was just thicker/used more material.
Also simple stone survives forever, while brick a bit less, and 'simpler mud bricks' and wood a lot less.
SO, from Roman times, really only the strongest buildings survived, and everything else is gone. So, there is a survivor bias. We are only looking at the strongest buildings, and not the average one.
And as their wealth was staggering, they could afford to build 'strong' more than most ancient civilizations and most of the conquerors just were assimilated rather than wanting to tear it down to the dirt.
The Romans weren't any more significantly wealthier than other contemporary Old World civilizations/empires - China, Persia, or India, for example. Conquerors being assimilated is a common theme that runs across most of these civilizations as well. However, monumental buildings that survive invading armies just tend to be dismantled/repurposed by the locals for the building material over time. I suspect that part of the reason for Roman monuments surviving is that the fall of Western Rome lead to an overall decrease in the urban population & subsequent demand for building materials. China, India, & Persia likely saw no such population decreases.
Using survivor bias to our benefit though. Evolution for buildings as it were.
While the article title is a blanket question on ALL Roman monuments
- which clearly didn't all survive - the article is about people investigating how the long lasting ones do what they do.
You're right to not buy this entirely. Roman concrete was great because it could harden while in water. And waterworks was probably the primary reason why Rome was such an early superpower (for multiple reasons: hygiene, stronger ports and also mechanical force, as "free" energy give you productivity increases. But it had less tensile strength than our current concrete.
The reason why multiple structures still hold today and will hold longer than most of our structures is more simple than that: they over-engineered the shit of everything that still hold today. Also for the same reasons, multiple bridges, castles, church or structures built between the low medieval era and high med/renaissance will likely last as much as roman structures did.
The explanation in the article is fascinating, but I wonder how much the Romans knew about the durability of their concrete at the time, and to what extent they just got lucky by the mix of material that happened to be available in their area.
I feel like a single human could trial and error their way to a very good paper airplane over the course of 2 or 3 days. It seems pretty obvious that a large group of people would trial and error products in much the same way, especially those so essential to their civilization. Especially with the large trade networks that we know to exist back then.
Aliens are incredibly unlikely. The Egyptians had grain money with demurage fees which encourage hundred year+ projects. Anything they did had a discounted future value that was higher than present value. Building something that lasted 4000 years was economically viable for them.
Right, of course aliens are extremely unlikely. The reason it is even talked about is because there are few convincing explanations how the Egyptians could theoretically have built the pyramids at that time.
I spent a few months devouring information on geopolymers. This theory seems very likely. But, Davidovits is the only researcher that has published on the subject that I have seen.
Does make me wonder what we’re building today that will last. I suppose the engineers who worked on Voyager or Pathfinder have the best shot of having built something enduring.
Sure, but the fact that some monuments have held that well is impressive.
It might have been a happy accident, it most likely was, but the valuable insight here is that we know that there is a recipe for concrete that lasts for thousands of years in real world conditions. We probably can do better today, we have a much better understanding of chemistry and computer simulations, but what we can't do is conduct a thousand year long experiment, and that's the Roman empire have done to us.
I wonder if there will come a time when society decides it's better to fix ruins such as the Colosseum and the pyramids instead of letting them just rot away.
With the Colosseum at least, it didn't just sit there untouched for two thousand years. The locals have repaired it after disasters. And also partially torn it down. And then rebuilt it.
About 150 years after it was built, it was partially destroyed by fire. And rebuilt. Another 200 years later there are inscriptions from late emperors who did more repair work. In the medieval era it was stripped of marble and suffered serious damage from an earthquake. In the 18th century it seems the Popes started to appreciate that it was historically significant, and various repairs and preservation activities have gone on ever since. One of the largest cleanings and repairs ever has just started in the last decade.
How much to repair though? At a certain point you have to start taking out original work to replace the ruined interior, and I can understand the extreme reluctance to do that.
As to the Pyramids, they've been rotting for 4300 years and they're still there mostly intact. The most severe damage was intentional acts in relatively recent history. As long as we don't decide to start tearing them down again for free stone, they'll probably outlast humanity.
It blows my mind that the Great Pyramid of Giza was the tallest building in the world for 4,440 years (give or take 10), until the Eiffel Tower finally dethroned it.
IIRC there was a protective limestone layer with a gold cap (removed for use in other buildings by later civilizations) on top of the pyramids versus leaving them as is, they originally did not look like unfinished stone. There is constant wind erosion on the exposed stone layer now. I don't know what a good solution to this now.
I think it would be cool to imagine ourselves as part of the process of civilization that created these buildings and restore them to their former glory. If the Mona Lisa was ripped in half we would surely restore it back to a single piece. Why should we not rebuild ancient Rome and host pop-up shops and events in the Forum?
It is an interesting thought, but I think your example doesn't work. In that we have two complete halves in need of minor repair. For ruins, we have parts left, and don't really even know for sure what it's supposed to look like. I mean, a very good idea, but not for sure.
And especially, over time, you can end up with a bit of a ship of theseus.
Also interesting -- if some day one of the earthquakes there knocks down part of the colosseum, will we rebuild the ruins to their ruinous state?
They’re not. The Romans built a huge amount and much of their artistic architectural works remaining today were purposely preserved, even if reused for some alternative purpose.
Yes, there are some construction techniques they used that contributed to better survival rates than some other structure types. But mostly we’ve ended up with what was lucky enough to survive. Replay the historical tape again and we might be surprised by what didn’t survive war, fires, other natural disasters on the second go round.
> for the same reasons we preserve Victorian era buildings.
Not really, christians destroyed a huge amount and ruthlessly, and tons of marble was 'repurposed'. The best chance of a building to survive was being used as a church
What’s crazy there is that by the mid-1800s, sketches would only show a portion of the column due to the rise in ground level over the intermediate period.
Destroying symbols of a previous rule was (is) commons practice. Constantine realized that some building and monuments were worth preserving and repurposed them as "Christian", thereby ensuring their preservation for hundreds, or even a thousand of years.
I suppose I just don’t find that substantially different than the National Trust repurposing say Ickworth into a hotel. I understand that contemporary society places a higher value on a certain type of “accurate” preservation than many societies that came before but if people had truly wanted historical Roman buildings gone, they would be.
Those garish colors probably aren't the real colors either. The researchers found one speck of paint and assumed the whole surface was the same color, when in reality the paint probably had complex gradations of color, like any normal painting. There is no need to assume the painting was less sophisticated than the sculpture underneath it.
I agree? My original reply’s point was we have a very small minority of what the empire constructed. And much of that is because it was purposely preserved, if for alternative reasons.
You respond to an article detailing the superior durability of Roman concrete with "they just chose to preserve these buildings" and "they just got lucky", cite no sources, and this is the top comment on this thread?
Seems HN quality has gone downhill since what I last remember.
Perhaps because there are enough people here who have been around for the dozens of comment threads we’ve had about the Roman concrete meme and how the notion that it is A. superior and B. a recipe completely lost to time is very much an extreme simplification of the situation.
Rather than spend my effort fighting a battle others have fought, here is an older HN thread with good commentary on the topic and links to countless previous discussions as well. https://news.ycombinator.com/item?id=22580920
I thought I'd find a lot of references to it not being (A) superior in that thread, but I actually didn't find much of anything supporting your point. Maybe it's deeper in the dang linked threads but I'm not that motivated to find evidence supporting you.
Here’s a thread from 6 months ago where there is significant discussion about why concrete is used the way it is today. Those parameters/considerations differ from those that the Romans would have faced. And, again, we only have the best examples of Roman cement today available for analysis versus the very wide range of construction quality that occurs today.
The very article linked also explains some of the limitations/ways in which Roman cement isn’t ideal/superior - for one, the massively longer curing time.
I don’t have the energy to revisit the arguments about Roman concrete that come up every time it is mentioned on HN. Needless to say, the notion that their “superior” method was “forgotten” is a massive oversimplification of what actually happened.
Another comment made my point better than I did - which was that Roman buildings that remained standing did so because they were useful for some purpose, often an alternative one (such as a church). It speaks to their value specifically as architecture and is mostly orthogonal to their construction techniques. There are plenty of old buildings (such as Hōryū-ji, Ruwanweli Maha Seya, Mousa Broch, etc) that don’t use any kind of magical construction techniques but have stuck around because of their value to the surrounding society and active efforts at preservation and/or repurposing.
> There are plenty of old buildings (such as Hōryū-ji) that don’t use any kind of magical construction techniques but have stuck around because of their value to the surrounding society and active efforts at preservation and/or repurposing.
This is true, but rather misleading. Hōryū-ji burned down and is probably around 80-90% new material.
The Roman concrete structures on the other hand survived this long with their original construction materials.
> which was that Roman buildings that remained standing did so because they were useful for some purpose,
that's a fallacy.
A lot of buildings were useful back then, it wasn't easy to build them nor cheap.
But most of them collapsed, because they weren't strong enough.
You get roman buildings everywhere in Europe and Northern Africa, a lot of civilizations lived there in the past 40 centuries and their remains are scarce at best.
It is like saying that Amazon beat many other startups of its times because they got lucky, it's simply because their execution was better than the competition.
There are very few Roman buildings that had survived intact. Besides the theaters and aqueducts there are basically none which were not later turned into churches. While Roman buildings might have been stronger than those built by the preceding civilizations (then again in the case of Europe (outside of Greece) and Northern Africa Roman there was very little competition, who else built massive coliseums at the the time?) most ancient buildings did not just simply collapse due to age but were destroyed by people who wanted to reuse their building material.
Trust me, the Domus Aurea was never a church, Villa Adriana has never been a church,they are both UNESCO's World Heritage Sites.
I think the misunderstanding comes from the fact that romans built several Basilica (for example the Basilica of Maxentius and Constantine), but for romans basilica meant a different thing: from the Greek word "stoà basileiós" the term basilica refers to the function of a building as that of a meeting hall. In ancient Rome, basilicas were the site for legal matters to be carried out and a place for business transactions.
Most of them never became religious buildings, they remained public places to meet other people.
> most ancient buildings did not just simply collapse due to age but were destroyed by people who wanted to reuse their building material.
that happened to roman buildings as well, Colosseum is maybe a third of what originally it was made of, but it's still standing and survived a massive earthquake in 1349 that opened a huge crack in it, but didn't destroy it.
Yes there are plenty of relatively well preserved Roman ruins, neither Hadrian's Villa or Domus Aurea had survived intact.
I'm not denying that Roman construction techniques were advanced, but it's not like we have much to compare them against. Sure, there aren't as many well preserved Etruscan or Greek ruins in Italy, but they preceded the Romans, had way less resources and not as advanced technology. And the same happened to the Romans who were eventually surpassed by medieval and renaissance Europeans. There magnitudes more surviving medieval buildings compared to Roman buildings, just like there are magnitudes (I would assume) more Roman ones compared ones built by Etruscans/etc.
But that does not mean that Roman architecture was somehow inherently superior. For example had the Carthaginians or some Greek state conquered the mediterranean instead of the Romans (obviously that was unlikely due to various non architecture related reasons) and had the resources to build as much as the Romans did would less of their buildings have survived or would they have been of worse quality everything else staying equal?
> and had the resources to build as much as the Romans did would less of their buildings have survived or would they have been of worse quality everything else staying equal?
Thanks for the question.
It would be a very long discussion to have in details, starting from the fact that even in ancient Rome there was some culture of preservation, like the restoration of 82 temples in the programs of Augustus (see “Preservation Practices in Ancient and Medieval Rome”), but it wasn't until 15th century that a real program of preservation and protection of old buildings was created by the papacy.
Rome was, more than any other city of its times, subject to invasions and destruction of its ancient monuments, used as construction material for new buildings and churches.
The need for churches was actually more a detriment than a a blessing.
The capital was moved to Constantinople more than a century before the sack of Rome and the fall of the western Roman empire, its monuments, its marbles, its travertine, its bricks, have been for more than a millennium up for grabs, by many conquerors.
In Greek cities, for example, there were no monuments to steal from, because they had been ruins for centuries already, Rome almost disappeared during the middle ages and, but the need for materials and the sacks never stopped, making new buildings, every time larger and richer, was the new normal, it was probably the most prolific period in history.
The fact that so many Roman buildings survived despite most of the original material was removed and used somewhere else, it's kinda miraculous.
Take for example two great historical figures: Alexander the great and Genghis Khan, their empires were immense, some of the largest in history, but buildings of their era are virtually non existent.
It wasn't their strongest trait, they were not builders.
Compare them to the Mesopotamians or the Egyptians and it becomes easier to see the difference.
Greeks influenced a lot both Etruscan and Romans, but it was more of a style.
Advanced construction techniques in Etruscan region were brought directly by Greek natives, but only the most privileged classes built proper houses, the rest of the population was living in villages made by tents or wooden shelters.
In East Asia, Japan in particular, most "old" buildings are reconstructed fairly often. They might reuse a lot of the old supplies, but many are very much a Ship of Theseus. Roman structures are, for the most part, preserved as they were--not fully disassembled and rebuilt.
One thing is that most places with extremely old structures have them far and few between. A 2000 year old building that wasn't rebuilt from the ground up is often a symbol of national pride for a country and seen as somewhat of a miracle that it's still standing. What makes Rome unique is the city alone is full of such structures, and it's a living, active city. In other countries that had a Roman presence, many of their oldest structures are remains built by Romans.
Most Egyptian structures were buried under sand for millennia and well-preserved as a consequence of that. I have to wonder how they'd hold up if they were in a different climate and with humans bustling about constantly into the modern era.
Either way, Romans were clearly doing something special.
The Roman period was followed by general population contraction and a total collapse of urban centers. The city for Rome itself did not reach the population it had in the 200's AD until the early 20th century. Of most ancient Rome was an abandoned or sparsely inhabited ruin (much like many other Roman cities) which is why so many buildings survived.
If Rome had remained a densely inhabited city most of the ruins would had likely been completely destroyed and built over (besides a few temples which were converted to churches). If we look at smaller Roman cities like Cadiz, London, Paris, Milan etc. there aren't that many traces of Roman times there because their population levels eventually rebounded during middle ages.
This is probably a rehash from your linked thread, but... perhaps it's both? Better construction materials used in buildings that had the most value in their architecture and/or purpose?
The article did bring up some ways modern concrete is superior in the shorter term:
"Among the biggest obstacles to wider adoption of the Roman recipe are its long curing time – it can take up to six months to reach full strength, compared to standard concrete's' 28 days – and lower strength (Perucchio said it's approximately 10 times weaker than modern concrete),"
Some of this is likely due to high lime content, which is self healing. Generally lower strength, longer cure time, but does not get attacked as hard by water due to remineralization. It is similar to how limestone naturally forms (think stalactites).
There might be some truth to Roman concrete still being reactive leading to its longevity, but I'd be really careful about dismissing survivorship bias.
> but I'd be really careful about dismissing survivorship bias.
I completely agree, we can't dismiss survivorship bias.
But let's imagine we are in a speculative historical sci-fi novel.
An ancient civilization makes contact with an alien one and they gain access to a new powerful way of building that had no precedent in history.
Fast forward 50 years, aliens are gone for good, there's no easy way for the layman people to access documentation let alone understand it, people will obviously don't understand what's going on, but they would see older buildings collapse after a mild earthquake or be destroyed by a wild fire, while some of them would survive, mutliple times.
They would most probably think of them as safer structures and give them more value and try to preserve them because of their "magical" ability to survive catastrophic events.
They would probably think of those buildings as gods gifts or sth like that.
Imagine that instead of 50 years it went on for almost a millennium.
And then the knowledge on how they were built got lost.
We shouldn't also dismiss more practical reasons, why build a new church if you can reuse one of the abandoned Roman temples? Why build a fortress to protect yourself from your enemies if you can just patch up some holes and install a gate to the Coliseum (or just convert some emperor mausoleum to one)? Even if people were fully aware (and at least the more educated ones were) that there was nothing magical about Roman construction they simply had no need to build anything similar themselves when they could just reuse the already present structures (either directly or as building material).
The standard approach to trash back then was to throw it in a pile nearby. Picking through those dumps can be really fascinating and a surprising amount of items are still in good shape. A simple heuristic for how old a glass bottle is is how thick it is. A modern beer bottle looks paper thin compared to one a century old.
Looking at old structures and tools really makes vivid how disposable many modern items are.