1. Granular materials under shear and pressure
Lettuce crops sheared by a geological fault
Allyson Rice, Matt Harrington, Professor Wolfgang Losert

2. What are granular materials?
Discrete macroscopic particles
Solids, liquids, and gases
commons.wikimedia.org
physicscentral.com 

3. Index matching to image grains in 3D
camera
acrylic tank
Index matched liquid
635 nm lasers
motor
0.06 degree/s
5 cm

4. How do we track grains in 3D?
Dijksman et al. (2012)
1. Locate particles
2. Follow motion

5. Grains move differently under pressure
No pressure
Pressure

6. Conclusions & Acknowledgements
3D tools to study sheared grains under pressure
Analysis is extensive!
Shear zone formation, vorticities in flow, mean square displacements (see poster)
Thank you…
TREND & NSF
Losert lab
Professor Losert
Matt Harrington
Nolan Ballew
And you 