Another thing that you can do with the Emriver plastic sand - build reinforced sand castles using layers of window screening for the geotextiles.
Here you can see the individual compacted layers of sand in between the window screen material. With about 80 pounds of weight on top of it.
Here I am pondering the strength of mechanically stabilized backfill.
And add a professor to bring everything up to over 220 lb (about 100 kg). All that supported by a humble little pile of reinforced sand.