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Pozzolanic concrete with basalt rebar supposedly addresses the spalling and other issues with long-duration reinforced concrete use cases. There are various poz
by yourapostasy 9y ago
Pozzolanic concrete with basalt rebar supposedly addresses the spalling and other issues with long-duration reinforced concrete use cases. There are various pozzolanic concrete recipes being tried to reproduce the list Roman recipe. No one I can find has combined the two and stuck it in seawater for 50+ years, though.
- stevenwoo 9y agoThe sea water theory in the article does not adequately explain the aqueducts still standing in Europe in Italy/France/Spain/etc after 2000 years with no contact with salt water after construction, although I am not certain if the concrete in those things is used in a structural way similar to what would be expected of buildings.
- yourapostasy 9y agoMy limited understanding trying to find out more about pozzolanic concrete (planning for my house extension in about a handful of years) is that those who study this stuff believe it stood up by itself like when used in the aqueducts with plenty of strength and durability, without constant immersion in salt water. Don't know if someone has drilled a core sample into those aqueducts to try to determine if salt water was used to mix that Roman concrete, though; would be interesting to find out. What drew attention to it was that modern concrete immersed in seawater, even without rebar, doesn't appear to have the same durability as ancient Roman concrete. Don't know how much of this is attributable to survivorship bias, though; would be unfortunate if all this attention turns out to be over a tiny fraction of a percent of ruins that happened to survive.