If all goes well, the inventors hope to develop the idea and make the sections entirely from recycled plastic.
Paths, car parks and railway platforms could follow. Eventually, sections for use as actual roads are planned.
These could contain sensors for traffic monitoring.
In time, the circuits in the plastic roads might extend to assisting autonomous vehicles and recharging electric cars wirelessly.
Prefabricated plastic roads should last two-to-three times longer than conventional roads and cost less, the companies claim,
mainly because construction times would be reduced by almost two-thirds.
Anti-slip surfaces could be incorporated, too, including crushed stones which are traditionally used to dress road surfaces.
The sections, when replaced, can also be recycled.
But engineers will be watching to see how the track stands up to wear and tear and if the hollow structure causes resonance,
which would make such a road unduly noisy.
An alternative method of using recycled plastic is to mix the material into hot bitumen when making asphalt.
A road is about to be built this way on the campus of the University of California, San Diego,
to test a number of specialist roadmaking plastics developed by MacRebur, a British firm.
Each mix is produced from plastic that is not easily or cheaply recycled and so typically ends up in landfill,
says Toby McCartney, who founded the firm in 2015 with a group of colleagues.
MacRebur cleans and sorts the plastic and then grinds the waste into flakes or pellets.
The plan is for this part of the process to be carried out in the localities where roads are being laid or repaired,
so that local waste is used to produce local roads. Each mix can contain 20 or so different polymers for specific surfaces.
One mix, for instance, might be suitable for a bus lane that carries heavy loads.
Another would provide some flexibility in an area of turning traffic, such as a roundabout,
where lateral forces from vehicles' wheels can stretch the surface causing it to tear. Extremes of heat and cold can also be adjusted for.
And because the addition of plastic helps to seal up small holes,
which allow water to get below the surface of a road and cause it to break up, the modified asphalt can help to prevent potholes.
The company's plastic mixes have already been used in roads, carparks and airport runways in various parts of the world.
One of the oldest projects is a stretch of road in Cumbria, in north-west Britain, which is extensively used by heavy lorries.
This used to need resurfacing every six months or so, but with the addition of plastic it is still going strong after two years, says Mr McCartney.
When resurfacing is needed, the material can be recycled again.