Re:Lost Advanced Civilizations
by WJW on Wednesday August 19, 2020 @06:25AM
(#24208900)
It's just a different tradeoff. We could absolutely make "Roman" concrete that lasts millennia, but it has a much lower strength than modern concrete so you can't make something like a harbor quay out of it. That said, "lasting a thousand years" is not as useful as it sounds, 99+++% of buildings will need to be demolished before that time anyway.
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> you can't make something like a harbor quay out of it
Are you sure about that? The Romans built a lot of harbours. We don't really have any data on the compressive or tensile strength of Roman concrete so it's hard to say for sure.
You can't make a _modern_ harbor quay out of it, one that is strong enough for the super large container cranes. The main problem is of survivorship bias: all the flimsy Roman harbors have disappeared so yes, only the most sturdily constructed ones remain. They would still not last under the "modern" load of 40+ ton vehicles.