Hidalgo Raúl Cruz, Zuriguel Iker, Maza Diego, Pagonabarraga Ignacio
AMADE, Departament de Física, Universitat de Girona, 17071 Girona, Spain.
Phys Rev Lett. 2009 Sep 11;103(11):118001. doi: 10.1103/PhysRevLett.103.118001. Epub 2009 Sep 9.
We present an experimental and numerical study on the influence that particle aspect ratio has on the mechanical and structural properties of granular packings. For grains with maximal symmetry (squares), the stress propagation in the packing localizes forming chainlike forces analogous to the ones observed for spherical grains. This scenario can be understood in terms of stochastic models of aggregation and random multiplicative processes. As the grains elongate, the stress propagation is strongly affected. The interparticle normal force distribution tends toward a Gaussian, and, correspondingly, the force chains spread leading to a more uniform stress distribution reminiscent of the hydrostatic profiles known for standard liquids.
我们展示了一项关于颗粒纵横比对粒状填料的力学和结构特性影响的实验与数值研究。对于具有最大对称性的颗粒（正方形），填料中的应力传播会局部化，形成类似于球形颗粒所观察到的链状力。这种情况可以根据聚集的随机模型和随机乘法过程来理解。随着颗粒变长，应力传播会受到强烈影响。颗粒间法向力分布趋向于高斯分布，相应地，力链扩展，导致应力分布更均匀，这让人联想到标准液体的静水压力分布。
