A fabric developed by scientists from Germany's Fraunhofer Institute for Wood Research and the SenAD2 project, monitors the condition of paved roads. The material consists of flax fibers interwoven with an electrically conductive sensor wire less than 1 mm thick. The fabric is produced on a double rapier loom in a width of 50 cm (19.7 in) at whatever length is needed. Side-by-side connected lengths of the material are laid down across the base layer of a road, as it's being constructed. The surface layer is then poured over top, covering them.
At the side of the road, an external measurement unit is connected to the sensor wire. As cracks proceed to form in the asphalt over the months and years that follow, the material expands, placing pressure upon the sensor wire. This creates a change in the electrical resistance of the wire, which is detected by the measurement unit. AI algorithms determine the current extent of the damage, and to provide an estimate of its likely progression over time. The technology is currently being tested on an industrial road in Germany.
More information:
https://newatlas.com/good-thinking/electronic-fabric-asphalt-roads/