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Building on the Romans II

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jmw

Industrial
Jun 27, 2001
7,435
GB
When we look back at the Romans, we do so across a period of time during which many of their skills were lost to whatever cultures and civilisations followed them. But it seems we credit developments to the wrong people all the time.
Normal I guess.

In this case it now seems the Romans didn't invent cement, or if they did, it was a rediscovery; the Macedonians now are the earliest so far believed to use cement.


The Romans certainly exploited cement extremely well and advanced the technology to cements that set underwater, to the use of pumice for lightweight concretes and so on.

My question is about the evolution of ideas and technologies.
Once you have cement and concrete, what comes next in the evolution of materials?
Should we expect they would have gone on to the development of steel re-inforced concrete, high rise buildings (would there have been a Roman Otto and the revolving door?)

What stopped them?
Where should they have gone with their other related technologies and would they necessarily have followed the path we followed with the discovery of Portland Cement? What other path might they have followed?


JMW
 
Everything.

I had a longer reply, but it got mushed. James Burke's "Connections" series provides a partial answer, in that every major advancement is not about a single, or singular, invention or discovery. There are a confluence of many factors, some monumental, others, trivial, that contribute to the overall advancement.

You asked specifically about steel reinforcement, from a culture than had barely made it into the Iron Age. But, what about welding, and riveting, and even just nuts and bolts? Without these rather mundane things, steel, or even iron, construction is impossible.

And let's say that some Roman architect dreamed about building multistory condo development to place next to the Coliseum. How was he going to get bath water to the top story, since he only had gravity fed aqueducts? How would the residents dispose of their wastes. How would they light their dwellings without pressurized gas?

How would this architect prove mathematically to his clients that the structure was sound, given that structural analysis would not be developed for nearly a millenium?

These are the mundane answers for why concrete alone, or even steel reinforced concrete, were insufficient to result in the first skyscraper until 1884.


TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
IRstuff,

Maybe the best way to run this exercise is to work out the technology required to build a steel skyscraper.

The Romans actually did build some fairly large, multi-story apartment buildings. Rich people lived on the bottom floors, close to the street, close to the fountains where their slaves could draw water, and of course, close to safety in the event of a fire.

We need standardized, mass produced steel sections. We need standardised, mass produced fasteners.

To build a modern condominium with rich people in the top floor penthouse, you need elevators to transport them to the top, and you need a high pressure water system. The building must be fire resistant.

The big advantage of steel buildings is that they are cheaper are they not?

Tbe Romans were perfectly happy with bricks and cement put up by slaves.

Critter.gif
JHG
 
"The big advantage of steel buildings is that they are cheaper are they not?"

Not clear, but they are the only way to build 10-story+ habitable buildings. The first Chicago skyscraper is a landmark for a reason. However, the cost of that first skyscraper was probably considerably higher than anything one might have built out of other materials, simply because the learning curve was still steep, and there were things that hadn't been done before.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Well, the Romans supposedly had rules about how tall buildings could be - early building codes if you like, based on safety considerations if I recall correctly. So lets blame regulation for them not getting the first sky scraper;-).

Also, how much did the Romans themselves really 'invent' as opposed to beg/borrow/steel from the various civilizations they traded with/fought with/conquered?

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484
 
IRStuff, all your arguments could be applied to any stage of our society if we applied today's standards to the capability 10, 20 or even 50 years ago.
We could look at what you need to make a PC today and prove that the computer could not be developed from the knowledge and skills base of the 1960's.
It also assumes that we finally do have laptops etc. because everything that was required to achieve them was purposefully developed to that end.
SO what that the first Chicago building cost a stack of cash.
If you look at a whole range of modern benefits you'll see the same objection. Railways and subways, canals etc. All cost more than was profitable and the early pioneers often lost out financially but it still got done. There is no reason we shouldn't allow that the Romans could not find investors to lose their shirts on unprofitable firsts....


JMW
 
But, my point wasn't just about money, since, in my earlier post, I discussed the lack of other inventions that were needed to make a real skyscraper, besides just steel-reinforced concrete. But for the want of a single nut and bolt, a skyscraper could not be built.

Likewise, you could not have developed a laptop in the 60's regardless of how much money you applied, since the basic display technology didn't even exist in the 60's. Or the battery technology, or the memory technology, or the disk technology, or even just the processor technology. It wasn't until the early 80's that all the factors confluenced to result in the Osborne 1, and while one might be pressed to argue that it's a portable computer, it's still nowhere near a laptop, and it weighed more than 20 pounds and couldn't possibly run off anything smaller than a car battery.

Having the vision simply isn't enough; you've got to have ALL, or nearly all, the pieces more or less ready to go.

Just having concrete might have gotten the Romans to a rival to the Great Pyramid, but it still wouldn't have been habitable. Nor could they have gotten to even any of the cathedrals, simply because their concept of physics and forces were too nascent to come up with flying buttresses.

I see the Pantheon as kind of the pinnacle of Roman monumental technology and architecture. And while it is a multistory tall building, it's essentially a single story occupancy building.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
But that presupposes there would be no Roman Otto or no one to invent the revolving door.
And while their may have been no drive for high rise apartments, they did build plenty of things on a big scale. And in building big they certainly had the wheel crane and they used water powered wheels in mining.... and for pumping water out of mines. How big a step to some kind of water powered elevator - or slave powered.... they already had the aqueducts, all they need is some big overshot wheels and they're in business.

We shouldn't forget that Hero was around in 150 BC with his steam engine...... and many of the fundamental ideas were available - and how long, given the impetus, to develop better foundry techniques if they had the incentives.
This is referred to as the iron age but they did have crude steels, some of the properties coming from the use of charcoal in the forges and they certainly used bellows.
Rome too had its military industrial complex and whereas many of their weapons were "junk" they also had swords made by the folding process. In fact, from the 7th Century BC Greece they could even be thought to have inherited the manufacture of swords by layering different low carbon steels together through friction welding. Some of their swords were iron cored with steel laminations on the edges.
Their metallurgy, like much else could be said to be a work in progress.
It isn't enough to say they didn't have the other necessary technologies.
When we talk about inventions and progress we talk about an inevitability.... who invented the light bulb? it wasn't an invention out of the blue, several were working on it.
What you really need is the financial incentives, tax denari and a supply of investors prepared to part with their money for a good idea.

Do we suppose that as various different evolutions in different areas advance, that at any one time there is a mix of circumstances that could or should, with the right incentives, lead to the next step? and that the next step will always be the same? does gunpowder always lead to the atom bomb?

The question is, is the path from cement to skyscrapers the only logical evolution or is there some other path... given the Roman fondness for grand engineering projects, it doesn't have to be high rise apartments.
After the coliseum, perhaps the Astrodome? After the Pantheon something even more grandiose? Plenty of money in relgion.
And note that in the coliseum they were used a lot of carved stones with lead and iron joints.... how long before some synergy of ideas would lead to the next step?

Maybe the trouble was the Roman military machine was too sophisticated and their enemies too unsophisticated... if the enemies of Rome were able to get into an arms race then maybe there would have been a need for the ability to build stronger higher more robust fortifications...war is perhaps the greatest spur to innovation.

JMW
 
The Romans did have multiple arms races. On many occasions their enemy had technological (such as at Syracuse) or else tactical advantages partly due to different if not inherently superior weapon technology (composite bows & mounted archers). The Romans lost a lot of battles, even before the 'fall'.

In many ways it seems the Romans often eventually triumphed due to persistence, organization and superior resources.

They did have low rise apartments, and given the limited area available within Rome did have a driver for 'high rises' buildings. I believe height restrictions were imposed because of earthquake concerns - that I mentioned earlier.

Perhaps once the height limits had been imposed, there was less stimulus to even try and build higher.

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484
 
The Romans could have made steel reinforced concrete. Take a wrought chain and embed it in the concrete. Job done. Brunellesci's dome being a fairly famous piece of work using that (um well perhaps not as it turns out). Technology wise how far ahead of the Romans were they in the Renaissance?

Prestressing it is where the real advantages come. They could have done that I suppose, but you probably need to understand beam theory to see why, and even Gallileo couldn't get that right.





Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
You don't have to use steel for reinforcement I suppose.

Bamboo has been investigated for some time and used in some areas. Not sure if the Romans had Bamboo but perhaps some reeds such as papyrus might have been similarly beneficial.

Silk has also been investigated.



Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484
 
Again, compare the Pantheon to Notre Dame. You keep pushing on the financial "incentives," yet, Roman patronage was not that fundamentally different that Medieval patronage, so similar incentives and recognition was there.

I think you have to apply Shannon's other theorem to this problem, i.e., you cannot solve a problem before its time. Clearly, the medieval civil engineers could have had steel reinforced concrete as well, but they didn't go off and build Chicago's Home Insurance Building, either.

And part of that answer is whether you have a problem seeking a solution. The Home Insurance Building and the Equitable Life Assurance Building solved a specific problem of contradictory requirements, i.e., large floor space in a small physical lot. The ONLY solution to that problem was to build upwards, hence skyscrapers were born.

The Romans, therefore, in addition to not having any of analytical tools for determining strength of materials and fasteners, etc., also didn't have a need for skyscraper, so SRC was never sought for as a solution.

A similar argument might be applied to why the medieval weaponeers didn't build machine guns. And the answer again, is that there wasn't a perceived need. It wasn't until there was a requirement to apply massive amounts of ammunition in a small amount of time that the Gatling gun was developed for the Civil War.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
The Romans did have a self loading crossbow which was pretty neat...This is still in the realms of a possible myth but plausible according to mythbusters... and I seem to recall the Beeb also built one... and possibly were better at it than mythbusters... they achieved 11 bolts a minute rate of fire and with excellent accuracy....
(the what the ancients did for us series is on You Tube, of course).
Oh, and see here:
they also talk about the water wheel used to pump water out of the gold mines in Wales.


PS, for those of you who remember the "What have the Romans ever done for us?" sketch from the "Life of Bryan" here's a "What has the Beeb ever done for us?" parody/advert - damn, the licence fee was cheap in those days....

JMW
 
Fire safety was another consideration as to why building height was limited in Rome. Manual water pumps couldn't reach upper stories.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]
 
IRstuff,

The big problem with ten storey apartments and office buildings is getting up to and down from the tenth floor. The piece of technology required to make these things work is not steel reinforcement. It is elevators.

Gothic cathedrals in Europe were as tall or taller than ten storey buildings, and they were made of stone.

Tall apartments and office buildings are prestige projects. When the Romans wanted to show off, they built temples, colliseums, roads and bridges. When the ancient Egyptions showed off, they built temples, pyramids, and enormous statues of themsevles. When the Mongols wanted to show off, they captured cities, beheaded everyone and built pyramids out of their skulls. Our values are different.

Critter.gif
JHG
 
jmw,

I watched the Mythbuster's episode on repeating crossbows. I sort of agree with the "plausible" finding.

They competed against one archer. They should have competed against a team of archers equivalent to the group required to run the repeating crossbow.

Note the poor mobility of the crossbow. If the battle does not unfold as expected, the crossbow operators either flee without their weapon, or die heroically in its defense.

An important limitation of automatic weapons is ammunition. Roman arrows and crossbow bolts were hand made, one at a time. You cannot shoot them off at eleven per minute for very long. Consider Shaka Zulu's rule. Many weapons you shoot at your enemies can be picked up and shot back at you. The Romans did not have a huge technological advantage over their enemies.

Critter.gif
JHG
 
IRstuff, the Romans did have incentive for building up, walled cities meant that land within those cities could be expensive, particularly in Rome.

As mentioned several times they did build low rise tenements, which were probably 'high rises' compared to the average one story building.

I seem to recall seeing that the height limit was imposed due to concern about earthquakes.

They probably didn't care too much if the 'poor' had to traipse up 5 flights of stairs, though certainly much above that would have been impractical. Also creating a crude elevator shouldn't have been beyond them - they were able to lift big blocks up to the higher level of buildings. However being able to do so cost effectively may have been another matter.

As to the repeating crossbow, I think I saw the BBC or Ch4 reenactment and it was a Ballista not a cross bow as I recall. While the one they built was on the small side with relatively low tension etc. fundamentally Ballista are much more powerful than a conventional bow or even a typical crossbow (especially those without a winch). A regular Ballista can fire other types of ammo like stones, which mitigates the ammo issue, though I doubt the auto version could have - at least not as easily. One issue with it was that supposedly it was too accurate - all the bolts went in the same spot - and yet relatively difficult to change aiming point. So it's use in open warfare is limited. However, as a siege weapon it had potential.

There is evidence to suggest that when attacking fortified compounds the Romans would sometimes aim all their Ballista at what they assumed was a significant target such as the chieftains hut or similar and just bombard the hell out of it. A kind of Terrorism or psychological warfare hoping to scare the inhabitants into submission without a frontal assault.

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484
 
The greatest contribution of the Romans was the Empire itself. Pax Romana plus a broad, united region with good lines of communication and transportation gave the people of that time unprecedented access to ideas and technology.
 
Oh IRstuff,
you made the mistake I avoided....this time...
Parthenon = Athens
Pantheon = Rome

JMW
 
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