Comment Re:Deja vu (Score 1) 311
Glass (and obsidian for that matter) are crystalline in structure, making them hard and brittle. Exactly what you do not want in a road surface. Rock on the other hand is usually an amalgam of several materials, meaning that it can be scraped and chipped, but is less likely to develop cracks that propagate. Using regular ordinary gravel in asphalt also means that the rock pieces are not subject to localized large forces, as the exposed surfaces of the gravel stones flex away thanks to the bitumen. The twin properties of flexibility and a hard wearing surface are what make asphalt able to stand up to being hit with tonnes of force hundreds of thousands of times a year and still last decades between having to be relaid.
I agree that it's probably not the case that we can't do better, but the question is about current materials technology and economic viability. Could we do better if we spent $1m per square meter of road surface? Possibly, with those newly emerging exotic resins and fibers. Would a $1m/sqm price tag mean that the project has any chance of success? No.