Our lab is interested in how granular materials fail, particularly through stick-slip motion, in ways that resemble earthquakes. Inspired by seismographs, we have been listening to the sounds the material makes as it evolves towards failure. In a new paper, we report our findings that the density of excited modes tends to broaden as the material looses rigidity, and ultimately fails. Next up: trying this out on actual seismological data!
“Sounds of Failure: Passive Acoustic Measurements of Excited Vibrational Modes.” Theodore A. Brzinski, III and Karen E. Daniels. Physical Review Letters. 120: 218003 (2018)
Some press releases describing the findings in lay terms:
- “Focus: Precursor Sounds Warn of Imminent Slip” Physics: 11, 52 (2018)
- “Granular materials emit characteristic sounds before slipping” Physics World (2018)
- NC State News Release
- Gizmodo.com