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How are Rome's monuments still standing?

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171–180 of 218 posts

Re: How are Rome's monuments still standing?

#171

Earlier quoted context omitted.

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 alternat…

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…

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.

Re: How are Rome's monuments still standing?

#172
post #8

Earlier quoted context omitted.

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…

To take one example of repurposing, amphitheaters turned out to make pretty good mini-fortresses, so in some cases the town simply moved inside!

Re: How are Rome's monuments still standing?

#173
post #166
post #57

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 n…

> A modern beer bottle looks paper thin compared to one a century old. I wonder if that is due to how much smoother transportation is now.

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.

Re: How are Rome's monuments still standing?

#174

Earlier quoted context omitted.

Aren't modern bottles designed for that too? Atleast here, you return them to the store, get some money back, and they wash and refill them

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.

Re: How are Rome's monuments still standing?

#175
post #165

Earlier quoted context omitted.

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.

Re: How are Rome's monuments still standing?

#176
post #9

Earlier quoted context omitted.

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…

I wonder how long carbon fiber rebar, or plastic coated steel rebar would last.

Briefly (costs/duration):

normal steel rebar=1

epoxy coated rebar=1.1-1.3 zinc coated rebar=1.2-1.4 stainless steel rebar=3-4-5 carbon fiber rebar=? What is used, not as "main" reinforcement but to have a (much better) mass strength are fibers, they can be either steel or plastic.

Re: How are Rome's monuments still standing?

#177

Earlier quoted context omitted.

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.

Just a thought: 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…

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?

Re: How are Rome's monuments still standing?

#178

Earlier quoted context omitted.

Nope. Romans invented concrete, and it was so good that still today the average concrete can't compete with it (its resistance to cracks is one example) Rewind history and roman buildings would still be there. They are thought to be one of the few things that would survive human extinction. The only thing that would outlast them are Giza Pyramids. https://en.m.wikipedia.org/wiki/Roman_concrete

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),"

JFYI, this is true also of modern Pozzolanic cement (almost unused today), but in my experience (anecdata) it is also stronger:

https://news.ycombinator.com/item?id=29377799

Re: How are Rome's monuments still standing?

#179

Earlier quoted context omitted.

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 peop…

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).

Re: How are Rome's monuments still standing?

#180

Earlier quoted context omitted.

Aren't modern bottles designed for that too? Atleast here, you return them to the store, get some money back, and they wash and refill them

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.

I've seen super scratched up glass Loka bottles in cafeterias... I wonder if they were used.
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