The role of particle shape on the stress distribution in a sandpile by I Zuriguel, and T Mullin Proceedings A Volume 464(2089): January 8, 2008 ©2008 by The Royal Society

Sketch of the experimental set-up. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Image of the particles as they are arranged within the pile. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Example of piles of (a) discs and (b) elliptic cylinders viewed through the two cross polarizers. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Monotonic increase of | ∇ I|2 when different vertical stress is applied to a thin layer of discs. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

(a) Close-up image of the chains that build up the stress network. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Vertical stress distributions estimated from averaging the results of 500 repetitions of piles built from a localized region with a mixture of 2500 discs with diameter 6.9±0.1 mm and 500 discs with diameter 8.9±0.1 mm. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Difference between the vertical stress profiles measured experimentally and the Gaussian fits for (a) discs, (b) elliptic cylinders and (c) pear-shaped cylinders when they are poured from a localized region at 57 cm. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Semilogarithmic plot of the chain length distribution for the mixture of elliptic cylinders. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

(a) Typical vertical slices used in processing chain orientation. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Probability distributions for the chain orientations calculated from 500 piles in a 1.5 cm slice located at d=3.0 cm from the centre of the pile: (a) discs, (b) elliptic cylinders and (c) pear-shaped cylinders. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Mean chain orientation for different positions along the x-direction of the pile. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Orientation of the elliptic cylinders in the pile. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society

Orientation of the pear-shaped cylinders in the pile. I Zuriguel, and T Mullin Proc. R. Soc. A 2008;464: ©2008 by The Royal Society