tony
Pro Roma
Chris Coles
The headline should have read; Strengthening by Orders of Magnitude" Three times stronger is a very significant result. If the follow up research can bring such results within a more reasonable timescale, then we can reduce the amount of concrete we use, again significantly reducing the carbon footprint of that otherwise crucial industry.
Geoff NH
The Roman concrete mixture had Pozzolans' as part of the Mixture and this is the secret to its corrosion resistance and strength. Also reduction of Portland type cement.
Pozzolans are found in Fly Ash from coal combustion.
Aross
So why do our concrete roads and bridges in Canada deteriorate after being exposed to salt water from road salt used here in the winter?
jerryd
All concrete gets stronger with age.
And we have been using the same materials for decades though from fly ash.
AbsolutJohn
This is absolutely true - and is the only reason why the city of Naples, Italy itself hasn’t been blasted into oblivion as it is sitting on a massive magma chamber, but the previous ancient eruptions have mixed with seawater and mineral deposits, creating a massive mile-thick pozzolano cement shield. Incredible.
Douglas Bennett Rogers
In my master's thesis I discovered that gypsum has a dihydrate to hemihydrate phase transition at 59 C.
bytheway
CO2 is not a pollutant.........it is a main building block of life on earth....and comprises less than 2% of the worlds atmosphere.....without it there is no life, period. Ice core samples taken in the arctic show up to 4 times current CO2 levels from the time when the arctic was tropical.....the vilification of carbon is part of the coordinated attack on civilization and the excuse to tax us out of existance.
Kpar
Three times stronger is not "an order of magnitude". That is 10x.

Yes, concrete gets harder over time (I'm not sure that that equates with "stronger"?). Concrete, I have been told, continues to harden for at least one hundred years. That is because concrete does not "dry", it forms a crystalline structure bridging the materials within as it sets.
McDesign
Hmm - seems generally, nuke plant concrete is a minimum of 6500 psi. Don't think that the jump to 20Kpsi is realistic.