### Abstract

The avalanche behavior of gravitationally forced granular layers on a rough inclined plane is investigated experimentally for different materials and for a variety of grain shapes ranging from spherical beads to highly anisotropic particles with dendritic shape. We measure the front velocity, area, and height of many avalanches and correlate the motion with the area and height. We also measure the avalanche profiles for several example cases. As the shape irregularity of the grains is increased, there is a dramatic qualitative change in avalanche properties. For rough nonspherical grains, avalanches are faster, bigger, and overturning in the sense that individual particles have down-slope speeds up that exceed the front speed uf as compared with avalanches of spherical glass beads that are quantitatively slower and smaller and where particles always travel slower than the front speed. There is a linear increase of three quantities: (i) dimensionless avalanche height, (ii) ratio of particle to front speed, and (iii) the growth rate of avalanche speed with increasing avalanche size with increasing tan θr where θr is the bulk angle of repose, or with increasing βP, the slope of the depth averaged flow rule, where both θr and βP reflect the grain shape irregularity. These relations provide a tool for predicting important dynamical properties of avalanches as a function of grain shape irregularity. A relatively simple depth-averaged theoretical description captures some important elements of the avalanche motion, notably the existence of two regimes of this motion.

Original language | English |
---|---|

Article number | 011306 |

Journal | Physical Review E - Statistical, Nonlinear, and Soft Matter Physics |

Volume | 78 |

Issue number | 1 |

DOIs | |

Publication status | Published - Jul 21 2008 |

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### ASJC Scopus subject areas

- Physics and Astronomy(all)
- Condensed Matter Physics
- Statistical and Nonlinear Physics
- Mathematical Physics

### Cite this

*Physical Review E - Statistical, Nonlinear, and Soft Matter Physics*,

*78*(1), [011306]. https://doi.org/10.1103/PhysRevE.78.011306

**Avalanche dynamics on a rough inclined plane.** / Börzsönyi, Tamás; Halsey, Thomas C.; Ecke, Robert E.

Research output: Contribution to journal › Article

*Physical Review E - Statistical, Nonlinear, and Soft Matter Physics*, vol. 78, no. 1, 011306. https://doi.org/10.1103/PhysRevE.78.011306

}

TY - JOUR

T1 - Avalanche dynamics on a rough inclined plane

AU - Börzsönyi, Tamás

AU - Halsey, Thomas C.

AU - Ecke, Robert E.

PY - 2008/7/21

Y1 - 2008/7/21

N2 - The avalanche behavior of gravitationally forced granular layers on a rough inclined plane is investigated experimentally for different materials and for a variety of grain shapes ranging from spherical beads to highly anisotropic particles with dendritic shape. We measure the front velocity, area, and height of many avalanches and correlate the motion with the area and height. We also measure the avalanche profiles for several example cases. As the shape irregularity of the grains is increased, there is a dramatic qualitative change in avalanche properties. For rough nonspherical grains, avalanches are faster, bigger, and overturning in the sense that individual particles have down-slope speeds up that exceed the front speed uf as compared with avalanches of spherical glass beads that are quantitatively slower and smaller and where particles always travel slower than the front speed. There is a linear increase of three quantities: (i) dimensionless avalanche height, (ii) ratio of particle to front speed, and (iii) the growth rate of avalanche speed with increasing avalanche size with increasing tan θr where θr is the bulk angle of repose, or with increasing βP, the slope of the depth averaged flow rule, where both θr and βP reflect the grain shape irregularity. These relations provide a tool for predicting important dynamical properties of avalanches as a function of grain shape irregularity. A relatively simple depth-averaged theoretical description captures some important elements of the avalanche motion, notably the existence of two regimes of this motion.

AB - The avalanche behavior of gravitationally forced granular layers on a rough inclined plane is investigated experimentally for different materials and for a variety of grain shapes ranging from spherical beads to highly anisotropic particles with dendritic shape. We measure the front velocity, area, and height of many avalanches and correlate the motion with the area and height. We also measure the avalanche profiles for several example cases. As the shape irregularity of the grains is increased, there is a dramatic qualitative change in avalanche properties. For rough nonspherical grains, avalanches are faster, bigger, and overturning in the sense that individual particles have down-slope speeds up that exceed the front speed uf as compared with avalanches of spherical glass beads that are quantitatively slower and smaller and where particles always travel slower than the front speed. There is a linear increase of three quantities: (i) dimensionless avalanche height, (ii) ratio of particle to front speed, and (iii) the growth rate of avalanche speed with increasing avalanche size with increasing tan θr where θr is the bulk angle of repose, or with increasing βP, the slope of the depth averaged flow rule, where both θr and βP reflect the grain shape irregularity. These relations provide a tool for predicting important dynamical properties of avalanches as a function of grain shape irregularity. A relatively simple depth-averaged theoretical description captures some important elements of the avalanche motion, notably the existence of two regimes of this motion.

UR - http://www.scopus.com/inward/record.url?scp=48349115358&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=48349115358&partnerID=8YFLogxK

U2 - 10.1103/PhysRevE.78.011306

DO - 10.1103/PhysRevE.78.011306

M3 - Article

AN - SCOPUS:48349115358

VL - 78

JO - Physical review. E

JF - Physical review. E

SN - 2470-0045

IS - 1

M1 - 011306

ER -