How the Pantheon, which was built over 2000 years ago, is still standing when buildings made 150 years ago are about to crumble.

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Edit- After reading most of the comments the general consensus is listed below:

1. The unique composite matrix of the concrete used gives it a self-healing property. When cracks form in the concrete, it will naturally seal them.
2. The Pantheon was a very significant structure which led to meticulous maintenance and restorations
3. The Romans didn’t have modern engineering. So they didn’t know exactly how strong they’d have to build the Pantheon to make it last. Their solution was to overbuild the hell out of it.
4. Survivorship bias. There were thousands of buildings constructed by the Romans but very few remain which are the ones we marvel at.

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33 Answers

Anonymous 0 Comments

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Anonymous 0 Comments

Meticulous mixing, adding of volcanic ash, limestone pieces, and heated when mixed.

There was a paper recently published that talked about it in much better detail. Aparently the limestone pieces in the mix would cause cracks to form there and with the later addition of water would cause a reaction to seal up the cracks.

Anonymous 0 Comments

Maintenance.

Anyone who says things like the ancients had “better materials” is just dumbing things down.

Is Roman concrete pretty good? Yea. Is it a magical building material? No. Can modern concrete match up to it? Yes.

The real thing is utilization, and maintenance.

For one. The pantheon only has people walking around inside of it. That is SIGNIFICANTLY less load than say, a bridge with semi trucks driving over it constantly. So it’s going to experience much fewer issues than the modern road.

And, it isn’t perfect, hell there was a really big restoration of the pantheon less than 100 years ago that fixed some pretty big cracks. But that’s the thing. For the entire existence of the pantheon, it was a Roman Temple built by emperors. So they had the money and motivation to take really good care of it. And then AFTER that, it became a church. And in that time the Catholic Church had the money and Motivation to take really good care of it.

Any modern structure that is crumbling is not crumbling because we are bad at building things. It is crumbling because no one has the money or motivation to fix it.

If we really wanted to, we could keep ANY building standing for 5,000 years. It would just take the time and effort of keeping it in good shape.

Anonymous 0 Comments

To add to other people’s answers, one thing to note is that Pantheon was a building of special significance, which means it got special attention. There are thousands of structures from that have crumbled a long time ago.

Anonymous 0 Comments

As one of my old engineering professors liked to say—“Anyone can design a bridge that doesn’t fall down. It takes an engineer to build a bridge that BARELY doesn’t fall down.”

The Greeks and Romans over-engineered. They built buildings that lasted 2,000 years longer than the clientele they were supposed to serve.

We could build structures that last that long today, with ease. We choose not to spend exorbitant money and time on creating something that might last 1000% longer than the desired design life.

Anonymous 0 Comments

A lot of concrete issues now are from the steel reinforcement.
The steel makes it stronger, so you can use less concrete, thinner walls etc.

Damp getting into the concrete makes the steel rust, and the expansion of iron into rust can exert massive forces and blow stuff apart. Roman stuff was done before steel reinforcement, so doesn’t have to contend with that, it was just made way thicker, heavier and stronger instead.

Anonymous 0 Comments

To add to what everyone else has said, there’s also what we call survivorship bias. The ~~Greeks~~ [Romans] built many buildings around the same time as the Pantheon, but very few remain. Those that do remain are the ones that were built to last and have received maintenance. The ones that weren’t are no longer here for you to talk about.

Modern buildings can also last a long time if they are well built and have regular maintenance. There are plenty of buildings that are 150 years old and are currently in good shape.

Anonymous 0 Comments

Fun fact, the Parthenon was used as a gunpowder warehouse during the 17th century and it was blown up during a siege. Without that incident it would probably be in a much better condition now.

*Edit:* Oops, I misread “Parthenon” instead of “Pantheon”…

Anonymous 0 Comments

The Pantheon was one of the most, if not the most important temple in ancient Rome. After Rome fell, it then became a church in the 7th century, again a pretty important one. It has been maintained and restored constantly since it was built. Thats why its still standing.

Meanwhile, if you go visit Rome today, you will find a huge amount of ancient roman ruins that were built before and after the Pantheon. But 99% of them are just that: ruins. A wall there, a pillar here, some small piece of mosaic there…

The reason the Pantheon survived and the other buildings didn’t was because it was maintained. And the reason 150 year old buildings today crumble is because they are not maintained. The ones that are can easily survive for hundreds and thousands of years. As a matter of fact, pretty much every city centre in Europe has buildings that are several hundred years old, and are in no way crumbling. Shit, the oldest church in my municipality was built in the 14th century and its still used today. We used to have band practice in a building that is first mentioned in 1320.

So yeah. The only reason 150 year old buildings are collapsing is cause they arent taken care of.

Anonymous 0 Comments

Over engineering and EXTREME income inequality.

Other people hit the over engineering point, but income inequality allowed it to happen.
When I took a few classes about the ancient world this was the one thing that really interested me as it really was insane.

I like to imagine the inequality as if we lived in a world where billionaires and millionaires still existed, but everyone else was either living on a dollar a day or was a slave. This was reality in the ancient world. The income inequality was almost unimaginable. Like there is more nuance than this but that sort of idea is roughly how unequal if was. There was the mega rich and the poor, that’s it. And a few just super rich mixed in. Also once there was an emperor they were worth more than almost everyone else in the empire combined.

Being this rich they decided to just spend money on some fun projects and so whenever they built something they could spend a ton of money on it. This allowed their over engineering to take place! Also since they were super rich they just kinda had a ton of money to spend on fun projects and make them look cool.

Edit: Oh I forgot the middle class: the legions of course