Research team recreates ancient underwater concrete technology

PhysOrg.com ^ | Apr 7, 2005 | unknown

[Mike Fieschko]

Found via RECONSTRUCTING ANCIENT TECHNOLOGY: Research team r... at Paleojudaica.com blog.

[Mike Fieschko]

ping

[Khurkris]

sub-aqua concreto pingo-rama

[supercat]

This reminds me of a radio program I heard a few years ago which suggested that the Pyramids in Egypt were fashioned out of synthetic sandstone. The person being interviewed [I forget what program it was--it was one I'd never heard of as I was driving hundreds of miles out of range of my usual radio stations] said that she'd determined a means of making synthetic sandstone using only materials and technologies which would have been present in ancient Egypt. Transportation of huge blocks would have posed much less of a technical challenge if they were ground, then transported, and then reformed.

[SunkenCiv]

Thanks Mike!

Please FREEPMAIL me if you want on, off, or alter the "Gods, Graves, Glyphs" PING list --
Archaeology/Anthropology/Ancient Cultures/Artifacts/Antiquities, etc.
The GGG Digest -- Gods, Graves, Glyphs (alpha order)

[SunkenCiv]

related topics:

Etruscan Engineering and Agricultural Achievements: The Ancient City of Spina
The Mysterious Etruscans
Last modified on Tue, 17-Aug-2004 15:36:27 GMT | editors
Posted on 08/17/2004 9:05:30 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1193229/posts

From Hand-drag to Jumbo: A Millennium of Dredging
IADC (International Association of Dredging Companies) | 1999 | IADC
Posted on 07/30/2004 8:27:24 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1181760/posts

[SunkenCiv]

Sounds like Margaret Morris, coauthor of Joseph Davidovits' book on geopolymerization processes possibly used by various folks, particularly the ancient Egyptians, to synthesize stones of widely varying sizes and uses.

http://www.geopolymer.org/science_archaeology/index.html

[SunkenCiv]

y'know, maybe Davidovits' stuff would make a good FR/GGG topic...

http://freerepublic.com/focus/f-news/799414/posts?page=16#16
http://freerepublic.com/focus/f-news/799414/posts?page=56#56
http://www.freerepublic.com/focus/f-chat/1368580/posts?page=20#20

[Nachoman]

I never knew concrete could be poured without Mexicans.

[supercat]

Sounds like Margaret Morris, coauthor of Joseph Davidovits' book on geopolymerization processes possibly used by various folks, particularly the ancient Egyptians, to synthesize stones of widely varying sizes and uses.

Thanks $1,000,000. That sounds exactly like what I was talking about, and it looks as though it's not some crackpot theory but is actually quite solid. I wonder why I'd not heard of that theory before the radio program?

[SunkenCiv]

The book came out, hmm, maybe 1983? Anyway, I picked it up from William Corliss' book catalog and found it quite interesting and compelling, unlike the "pyramids were water purifiers" or "pyramids generated electricity to run the ancient Dremel tools" claims. ;')

[ApplegateRanch]

Thanks for the interesting ping. It never ceased to amaze me what the Romans could do with sand/gravel, burnt limestone/gypsum, water, and a lot of laborers.

Any links/leads on the more nuts & bolts (or is that nails & pegs?) of the actual form building? My job used to entail building them; it was up to the mudders to fill them, so you can see where my interest is.

[SunkenCiv]

I'm a little curious about that myself.

The art of underwater concrete casting was perfected by the Romans, but their concrete was quite different from the concretes used today. I've seen the process reproduced (on a video of course) and with the addition of water the mixture started to "boil". The Pantheon in Rome, which in its time (and for some time thereafter) was the largest dome in the world, and is still standing, was constructed (if memory serves) of concrete.

http://www.ancientroute.com/cities/caesarea.htm
http://ancientneareast.tripod.com/Caesarea_Maritima.html
http://www.padfield.com/1996/caesmari.html

a translation online, by one Bill Thayer (I couldn't get it to load):
http://www.ukans.edu/history/index/europe/ancient_rome/E/Roman/Texts/Vitruvius/home.html

same work, different URL, now it's bedtime for 'Civ:
http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Vitruvius/home.html

http://www.vitruvius.be/index.htm

[SunkenCiv]

Oh, I like this guy already:

"Another orphan text that no one wanted to enter, but that many nevertheless will be glad to see online. (Why is it that the self-aggrandizements of Cicero, the lecheries and whining of Ovid and the blatherings of that debauched old goose Seneca made it onto the Net before the works that give us solid technical information about what Rome was really good at, viz. the construction of her great buildings and works of engineering?)" -- Bill Thayer

http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Vitruvius/home.html

[ApplegateRanch]

>>I've seen the process reproduced (on a video of course) and with the addition of water the mixture started to "boil".<<

Thanks for those links. Without looking further tonight---bad toothache---I'll guess the boiling was from using quick lime, calcium oxide:

1. n. [Drilling Fluids] ID: 1769

A chemical with formula CaO, commonly called quick lime or hot lime. When hydrated with one mole of water, it forms slaked lime, Ca(OH)2. Quick lime is used in preference to slaked lime at oil-mud mixing plants because it generates heat when it becomes slaked with water and therefore speeds up emulsification by the reaction to form calcium-fatty-acid soaps.

(http://www.glossary.oilfield.slb.com/Display.cfm?Term=calcium%20oxide)

The adding of water would convert it to slaked lime, the prime ingredient of 'natural' (as opposed to modern 'Portland') cement.

[Quick lime was also used sparing to sprinkle down the hole of outhouses, to control oder, insects, etc. It is also the lime used to sprinkle on dead critters until [if ever] they can be picked up by the knacker or animal control. It will burn the skin, which is why pre-slaked lime is used for such things as white-wash & plaster; it is safer.]

[Darkchylde]

Nah, everyone knows the pyramids were built by aliens in
order to generate power for the satellites that watch us.

;-])

[SunkenCiv]

Thank goodness for Reynolds Wrap. ;')

[SunkenCiv]

a few links and quotes:

The Pantheon-- Rome -126 AD
A temple to all gods - by Freda Parker
http://www.monolithic.com/thedome/pantheon/

"Though the Romans had been building with concrete since about 200 BC, work on the Pantheon was difficult and proceeded in gradual stages... Vitruvius (cir. 20 BC), a noted Roman architect, recorded the process followed in his day, that was probably still used by the Pantheon's builders. The ancients hand mixed wet lime and volcanic ash in a mortar box, adding very little water so that they got a nearly dry composition. They carried this mixture to the job site in baskets and poured it over a prepared layer of rock pieces. They then tamped the mortar into the rock layer. The tamping packed the mortar, reduced the need for excess water, but, at the same time, stimulated bonding... Eventually, work began on the concrete dome, constructed in tapering courses or steps that are thickest at the base (20 feet) and thinnest at the oculus (7.5 feet). The Romans used the heaviest aggregate, mostly basalt, at the bottom and lighter materials, such as pumice, at the top. They embedded empty clay jugs into the dome's upper courses to further lighten the structure and facilitate the concrete's curing. In the dome's construction, the Romans probably used temporary wooden centering on which they layered concentric rings of masonry and concrete."

[derivative material at http://www.aviewoncities.com/rome/pantheon.htm ]
http://www.aviewoncities.com/img/rome/kveit0301p.jpg

Pantheon, Rome
Wikipedia
http://www.answers.com/topic/pantheon-rome
http://www.answers.com/main/content/wp/en/thumb/2/28/175px-Ac.pantheon2.jpg
"The building is circular with a portico of three ranks of huge granite Corinthian columns (8 in the first rank and 16 in total) under a pediment opening into the rotunda, under a coffered, concrete dome, with a central opening (oculus), open to the sky. The height to the oculus and the diameter of the interior circle are the same (43 metres), so the whole interior would fit exactly within a cube. The dome is the largest surviving from antiquity, and was the largest dome in western Europe until Brunelleschi's dome of the Duomo of Florence was completed in 1436."

The Pantheon
By David Moore, P.E., 1995
http://www.romanconcrete.com/docs/chapt01/chapt01.htm

"Unrecognized, the design of this ancient concrete building reveals unparalleled features not encountered in modern design standards. Recent studies reveal several major cracks in the dome, but it still functions unimpaired. This condition will surely excite the curiosity of our structural engineers. The building was built entirely without steel reinforcing rods to resist tensile cracking, so necessary in concrete members, and for this concrete dome with a long span to last centuries is incredible. Today, no engineer would dare build this structure without steel rods! Modern codes of engineering practice would not permit such mischief. No investor with knowledge of concrete design would provide the funding."

also:
http://www.geopolymer.org/science_archaeology/roman_cement_concrete/high_durable_buildings.html

[SunkenCiv]

---

The Pantheon: Design, Meaning, and Progeny by William L MacDonald

---

[SunkenCiv]

GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach	join list or digest view topics view or post blog bookmark post a topic subscribe
Just updating the GGG info, not sending a general distribution. Posted April 9, 2005 To all -- please ping me to other topics which are appropriate for the GGG list.