Pyramid Stones Were Poured, Not Quarried

brian0918 writes "Times Online is reporting that French and American researchers have discovered that the stones on the higher levels of the great pyramids of Egypt were built with concrete. From the article: 'Until recently it was hard for geologists to distinguish between natural limestone and the kind that would have been made by reconstituting liquefied lime.' They found 'traces of a rapid chemical reaction which did not allow natural crystallization. The reaction would be inexplicable if the stones were quarried, but perfectly comprehensible if one accepts that they were cast like concrete.'"

Comments

(obligatory grains of salt)

[mmell]

Question 1: Is the activity of casting liquified lime depicted on any pictographs/heiroglyphics in Egypt? The ancient Egyptians had a marvellous habit of recording a great many things on very durable media - including how their own technology worked. I would expect to find depictions somewhere of Egyptians or their slaves engaged in the tasks of manufacturing and pouring concrete.

Question 2: Is there evidence that the Egyptians used this technology elsewhere? I find it difficult to believe that they would've evolved this kind of technology (concrete) and used it exclusively for the task of pyramid-building.

2nd time I've heard this

[jbeaupre]

The first time was when a researcher about 10 years ago (give or take 10) claimed they were poured because he found a human hair embedded in one.

That's cement, not concrete

[Beryllium Sphere(tm)]

There's no mention of aggregate, the sand and gravel that cement glues together to make concrete.

Re:Casting Vs Forming

[eldavojohn]

Or the Romans tried many times before creating Bath's and Aqueducts.

There's a lot of stuff out there that I can grind up and mold. It will last a day. It will last two days. It will last the week and it might even last the season. But when you come to a place of sand and you see these pyramids that have weathered the elements and retained a decent shape for possibly thousands of years, you might say, "What have you got there?"

I'm not keen on Roman/Egyptian history but I think that the Egyptian society and race are a bit older than the Romans. Wikipedia tells me that the Egyptian empire ran some 7,000 years while the Roman Empire technically only lasted only from 44 BC to AD 476. Ok so in 500 years, how many experiments with possible mixtures could you test. You can test for hardness & solubility on the fly but not duration. If you mix limestone with gypsum, you come up with something like drywall that won't last long at all in the elements. but might initially have a very hard composure.

Go look at some of the adobe structures that have lasted for hundreds upon hundreds of years in the Southwest of the United States. They were using the most abundant resource that was known to last the longest. R&D for the Romans was probably pretty high quality but I was just speculating that nothing then could match 7,000 years of research for something that would bring your leader's through the ages.

It was just speculation on my part but I highly doubt the Romans were the sole originators of the formula for the aqueducts. It really is too bad Alexandria was burned. If I could undo one thing in history, I would be tempted to pick that one.

Mortar

[kaoshin]

I always thought that the mortar used was more amazing than the blocks themselves. I had this book named the great pyramid decoded which explained that there were blocks held together with sheets of mortar that were in some places as thin as a sheet of aluminum foil. I have read elsewhere on the web that the chemical composition of the mortar is known but that it can't be reproduced today. I may be easily fascinated by this stuff, and there may be an better mortar now, but I just think that is really cool.

Meanwhile, a retired carpenter..

[Bob Cat - NYMPHS]

is building his own Stonehege - BY HAND, ALONE.

http://www.theforgottentechnology.com/

Re:so why then use blocks ?

[LurkerXXX]

Ding, Ding, Ding. Give that man a cigar.

You can't just pour something the size of the pyramids and expect to have it set in any reasonable time frame.

Ever see movies of the building of the Hoover dam? It was done in a lot of small blocks, and for a very good reason:

"The Bureau of Reclamation engineers calculated that if the dam were built in a single continuous pour, the concrete would have gotten so hot that it would have taken 125 years for the concrete to cool to ambient temperatures. The resulting stresses would have caused the dam to crack and crumble"

Re:It has to be said

[sofar]

"I'd suspect that maybe the stones at the base might have needed to be stronger than the ones near the top."

No.

The compressional forces that concrete or any mineral type of rock can endure are almost endless. man-made concrete is just as strong as some of the toughest rocks in nature.

You don't see the grand canyon walls (larger and steeper than any pyramid) collapse? Those are (top 100's of feet) made out of sandstone, which is probably not even as strong as concrete or limestone.