Scientists replaced 40 percent of cement with rice husk cinder, limestone crushing waste, and silica sand, giving concrete a rubber-like quality, six to nine times more crack-resistant than regular concrete. It self-seals, replaces cement with plentiful waste products, and should be cheaper to use.

[u/mvea]

https://newatlas.com/materials/rubbery-crack-resistant-cement/

[u/ljb23]

This should have a significant environmental upside too right? Traditional concrete is very emissions intensive to manufacture.

[u/hoadlck → u/ljb23]

I believe that the largest producer of CO2 in making concrete is in the production of cement: it has a large environmental impact. I don't think that this type of concrete will change CO2 usage. They are targeting this for buildings to be more robust against damage, so I don't think that there is a longer life for things constructed with it either.

[u/ljb23 → u/hoadlck]

Yep, I incorrectly used the word concrete when I was after cement.

Wouldn’t a 40% substitution represent a roughly proportional reduction in cement usage though?

[u/jbram_2002 → u/ljb23]

This concrete will likely require fiber-reinforcing, which is an expensive process that I assume is not significantly better for the environment. Unfortunately, I think the environmental impact would be relatively minimal.

[u/scindix → u/jbram_2002]

But couldn't fiber-reinforcing at least be optimized?

The environmental impact of electric cars is minimal as well. However as soon as we switch to renewable sources for electricity electric cars will be a way better solution.

The problem is that in contrast to electric mobility we can't optimize combustion engines any further. And the same goes for cement. The underlying chemical reaction produces CO2 and there's nothing we can optimize.

So any process that doesn't necessarily require the production of greenhouse gases should be an alternative that deserves a second thought. Or am I missing something?