It seems strange, but the world is running out of sand (see here; there’s also a fantastic book on the topic). The problem, in particular, is that sand is used in producing concrete, but only sand with grains that are shaped in a particular way will work.
Unfortunately, desert sand, which is plentiful, is weathered by the wind into a rounded shape that cannot be used for construction purposes. The kind of sand most commonly used for construction comes from a small number of places, and is increasingly rare (and hotly contested).
To turn granular sand into a useful building material, it is generally combined with cement (usually a limestone product) to produce concrete. In addition to using up vast quantities of rare sand, this also produces a lot of carbon dioxide (although there’s various work-arounds in development); construction is a significant source of this greenhouse gas.
What if we took a completely different approach to turning sand into a construction material though? One that can use any sand, even the most common of desert sands. One that does not require concrete at all.
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