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That is very true of all their concrete and indeed so many of their monuments are testament to that, in fact when I worked at Housesteads Fort we had a gang nicknamed the hole in the wall gang.
These guys were there to do small repairs to the wall and each year they found that their concrete could not stand up so well as the Roman, they set up various strains to test them over the years but they found they could not match the long lasting stuff the Romans had put there all those years ago.
The wall being 55 degrees north and many of the savage winters have ruined the modern stuff so much more than the wall itself.
Brian Stobbs
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I concur with Brian.
I have some small fragments from my excavations on the wall at West Denton in the late 80s, and it is amazing stuff!
Moi Watson
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, Merlot in one hand, Cigar in the other; body thoroughly used up, totally worn out, and screaming "WOO HOO, what a ride!
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Someone should contact Abby on NCIS and have her run a sample through her mass spectrometer, so we know exactly what it is made of
There are some who call me ......... Tim?
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Aw heck. Abby could tell you what it was made of, whether his wife was left-handed and what he had for lunch on the day he mixed the slurry. Give her some credit, Tim! :lol:
M. Demetrius Abicio
(David Wills)
Saepe veritas est dura.
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Just the fact that those pilings and bridge footings are still being used a couple thousand years later should tell us their concrete was better than ours. We often have to replace bridge pilings after just 50 or 100 years due to breakdown of the concrete.
M. Demetrius Abicio
(David Wills)
Saepe veritas est dura.
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Not really "news". There have been several investigations already over here, in the context of sustainability research for modern buildings. A lot published on this...
Christian K.
No reconstruendum => No reconstruction.
Ut desint vires, tamen est laudanda voluntas.
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I had heard that concrete gets harder with time, and that our modern practice of reinforcing concrete actually shortens its life, because exposed rebar can rust and introduce instability, but I didn't know the actual composition of ancient concrete was better than what we use today.
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I'm not an expert in this sort of thing, but concrete doesn't really "dry" as if it were water-based paint by the water evaporating. It is a thermochemical reaction that starts out hot, then gradually slows down. Somewhere I read that the curing process takes many years when there is much concrete involved. The Hoover Dam is still going through the reaction, for example, and still is generating heat. Exothermic the big brains call it.
The metal is to hold the whole block of concrete together in the event a stress is applied to it: helps prevent cracking in the first place, and holds the mass together in the event that it does crack, or at least that's the plan. I don't think the ancients used metal reinforcing, yet their concrete seems to hold together, lending some credence to the idea that it was a different formulation.
M. Demetrius Abicio
(David Wills)
Saepe veritas est dura.
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M. Demetrius Abicio
(David Wills)
Saepe veritas est dura.