Princeton University biomedical engineers say they’ve documented for the first time a voltage signal preceeding the failure of structures made of powder. It may not sound like earth-shattering research, but lots of things are, to a degree, made of powder: the cement in that bridge you drove over today, and the ground beneath your feet, to take two rather important examples.

The experiments they describe this week in Proceedings of the National Academy of Science started simply enough. The researchers filled a horizontal cylinder about two-thirds of the way with a powder, stuck a voltage probe to it and slowly rotated the cylinder. As you might imagine the powder sticks to the side until gravity takes advantage of defects in the powder’s packing, and a chunk of powder cleaves off like an Alpine avalanche. The technical term for this is a “slip event.” …..

For further reading, please open the following link : Electric Signal Might Warn of Collapsing Bridges, Failing Turbines, Earthquakes, and More