Particle shape is a major parameter for the space-filling and strength properties of granular materials. For a systematic investigation of shape effect, a numerical benchmark test was set up within a collaborative group using different numerical methods and particles of various shape characteristics such as elongation, angularity and nonconvexity. Extensive 2D shear simulations were performed in this framework and the shear strength and packing fraction were compared for different shapes. We show that the results may be analyzed in terms of a low-order shape parameter η describing the degree of distortion from a perfectly circular shape. In particular, the shear strength is an increasing function of η with nearly the same trend for all shapes, the differences being of second order compared to η. We also observe a nontrivial behavior of packing fraction which, for all our simulated shapes, increases with η from the random close packing fraction for disks, reaches a peak considerably higher than that for disks, and subsequently declines as η is further increased. Finally, the analysis of contact forces for the same value of η leads to very similar statistics regardless of our specific particle shapes.

JF - 7th International Conference on Micromechanics of Granular Media (Powders and Grains) PB - AIP CY - JUL 08-12 2013 Sydney, AUSTRALIA VL - Book Series: AIP Conference Proceedings POWDERS AND GRAINS 2013 ER - TY - JOUR T1 - Particle shape dependence in 2D granular media JF - EPL (Europhysics Letters) Y1 - 2012 A1 - Baptiste Saint-Cyr A1 - Krzysztof Szarf A1 - Charles Voivret A1 - Emilien Azéma A1 - Vincent Richefeu A1 - Jean-Yves Delenne A1 - Gael Combe A1 - Cécile Nouguier-Lehon A1 - Pascal Villard A1 - Philippe Sornay A1 - Marie Chaze A1 - Farhang Radjaï AB -Particle shape is a key to the space-filling and strength properties of granular matter. We consider a shape parameter