Alternative materials could shrink concrete’s giant carbon footprint

I don’t get this article. There is a “CO2 is bad mm’kay” problem statement, then a recommendation of fly ash, which is already a common additive to mixes, then a recommendation for mill slag, which is already a common additive where it’s available, then a recommendation to look at geopolymers, which I’ve never seen specified for any job anywhere and which are also useless for cast-in-place applications, and finally a time-will-tell conclusion. Is this content for content’s sake? Anything remotely practical mentioned has been in use for years.

Nice to see geopolymers mentioned. Geopolymers are becoming more common around the world. They can be formulated from local materials and in many cases have superior material properties to Portland cements. Joseph Davidovits of the Geoplymer Institute has been instrumental in the spread of his lifes work, geopolymers.<p>Davidovits also claims that many ancient megalitic constructions were made using geopolymers which fits with stories of technologies that soften rocks.<p>Geopolymer Institute is an amazing resource on the subject. <a href="https:&#x2F;&#x2F;geopolymer.org" rel="nofollow">https:&#x2F;&#x2F;geopolymer.org</a><p>Pyramids of geopolymer, <a href="https:&#x2F;&#x2F;youtu.be&#x2F;znQk_yBHre4" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;znQk_yBHre4</a>

C.f. BBC article today reporting on British engineers urging the construction industry to stop knocking down houses because of the carbon emissions of new builds:<p><a href="https:&#x2F;&#x2F;www.bbc.co.uk&#x2F;news&#x2F;science-environment-58667328" rel="nofollow">https:&#x2F;&#x2F;www.bbc.co.uk&#x2F;news&#x2F;science-environment-58667328</a><p>The 8% stat is surprising.

For housing, hempcrete [0] had shown a lot of promise with its insulating, anti-mold and moist repellent properties. Plus its CO2 binding and quite cheap.<p>[0] <a href="https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Hempcrete" rel="nofollow">https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Hempcrete</a>

Mmmkay, but concrete could also shrink the global carbon footprint. Mixing CO2 to concrete makes it hardening much faster and the result gets more durable.<p><a href="https:&#x2F;&#x2F;www.globalconstructionreview.com&#x2F;researchers-find-way-cure-concrete-co2&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.globalconstructionreview.com&#x2F;researchers-find-wa...</a>

Something that helps but is little-practiced is just making structures hollow. For instance instead of pouring 300 cubic meters of concrete for one of SFMTA&#x27;s absurd high-floor boarding platforms[1], some agencies are building similar structures that begin by placing hollow, prefabricated, fiberglass boxes and pouring concrete around them, reducing the total concrete in the project by an order of magnitude.<p>A little bit of engineering goes a long way.<p>1: <a href="https:&#x2F;&#x2F;www.google.com&#x2F;maps&#x2F;@37.7801361,-122.3895982,39a,49.7y,202.06h,64.97t&#x2F;data=!3m1!1e3" rel="nofollow">https:&#x2F;&#x2F;www.google.com&#x2F;maps&#x2F;@37.7801361,-122.3895982,39a,49....</a>

This article takes&quot;pushing out content&quot; to heart. I don&#x27;t anybody familiar with the topic learned anything here