4 ms·

None of the above is true.

• Llamamoe 1y ago
  Every single one of the above is true. The self-healing capacity of ordinary Portland cement is very limited, but it's there, and you can easily find literature backing this fact up, e.g.[1] You can also trivially look up strength figures of OPC concrete vs Roman concrete. Modern concrete is overwhelmingly stronger, and can be made even stronger where it needs to be. As for being subjected to incomparably higher stress... are you really claiming that Roman architecture was ever subject to anything comparable to thousands of multi-ton vehicles driving at dozens of kilometers per hour? Or to anything comparable to the weight of a high-rise building? And don't forget that it made heavy use of arches, which isn't necessary anymore thanks precisely to the strength of modern concrete. We also know what the composition of Roman concrete was, and there's literally thousands of publications on self-healing variants of concrete. You can buy most of them. They're just not a priority for most applications. People really need to stop romanticising Roman concrete. It was incredible, sure. But it's got nothing on modern cementituous material science. [1] https://pmc.ncbi.nlm.nih.gov/articles/PMC9302975/ https://pmc.ncbi.nlm.nih.gov/articles/PMC9302975/