> reinventing the highway pavement system A number of years ago there was a demo of a technology where they mixed (something like) iron filings in the asphalt.

> reinventing the highway pavement system A number of years ago there was a demo of a technology where they mixed (something like) iron filings in the asphalt. By slowly driving over it with a massive electromagnet they could heat the asphalt from within, helping to fix any small cracks before water ingress could cause a larger problem.