Using plastic waste to help solve sand shortages

Source - bbc article

I've mentioned the possible shortage of sand for use in concrete construction around the world before and - admittedly - haven't heard much of an update on that shortage in the past few years.

Today's article describes an attempt to solve the sand shortage - at least partially - as well as to use some of the seemingly endless supply of plastic trash that we continue to produce in our world by replacing some of that sand with ground up plastic pieces.

There isn't much detail, and I would want to know a few things before considering plastic as a sand alternative...

• Is the plastic post- or pre-consumer plastic?
• What polymers can be used for this?
• Does anything leach from the plastic over the life of the concrete?
• As the concrete structure wears, are microplastics released?
• How does the plastic change the hardness, toughness, strength of the concrete material?

In the long run, this might help extend our construction forward a bit, but I'm coming to realize that maybe we just need to use less stuff.