from Hacker News

We Know Why Ancient Roman Concrete Lasts Thousands of Years

by tomcam on 5/18/25, 1:39 AM with 15 comments

• by NaOH on 5/18/25, 4:09 AM

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• by mitthrowaway2 on 5/18/25, 2:42 AM

  Interesting. It's not just the absence of rebar, and it's not survivorship bias. It's a hot-mixing method that results in both rapid curing times, and self-healing of cracks. A lost technology, rediscovered.

• by chmod775 on 5/18/25, 2:56 AM

  > The team is now working on commercializing their concrete as a more environmentally friendly alternative to current concretes.

  That may be rough, given they won't be able to patent it due to prior art...

• by brador on 5/18/25, 9:04 AM

  Think. Blacksmiths folded metal. Makes sense they’d try the same with concrete, which would result in this auto healing we see. This seems the most likely method I would have invented but no one ever thinks of.