An insight into the yielding and normal compression of sand with irregularly-shaped particles using DEM
An insight into the yielding and normal compression of sand with irregularly-shaped particles using DEM
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DOI：
10.1016/j.powtec.2014.11.013
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发表时间：
2015-02-01
影响因子：
5.2
通讯作者：
McDowell, G. R.
中科院分区：
文献类型：
--
作者：
de Bono, J. P.;McDowell, G. R.
近年来，离散元法已揭示了散体土一维各向同性法向压缩的细观力学机理。通过将土壤颗粒建模为球体并实施新的破碎模型，作者之前研究了断裂机制、颗粒强度（和分布）以及尺寸硬化定律对法向压缩线和所得颗粒尺寸分布的影响;这导致了新的压缩定律。在这项工作中，引入了不规则的颗粒形状，使用“团块”（球形颗粒组），允许不同相对密度的相同材料进行正常压缩。屈服力学的调查，其中发病的破碎有关的平均颗粒八面体剪切应力和“屈服”被认为是一个可用的空隙空间的函数。除了屈服，正常的压缩线的团块在不同的初始密度进行检查，并比较球体。研究了配位数和颗粒形状对法向压缩的影响，揭示了分形颗粒尺寸分布演化背后的微观机理。(C)2014爱思唯尔有限公司版权所有。
The micro mechanics of one-dimensional and isotropic normal compression of granular soil have recently been revealed using the discrete element method. By modelling soil grains as spheres and implementing a new crushing model, the authors have previously investigated the influence of fracture mechanism, particle strengths (and distributions), and the size-hardening law on both the normal compression line and resultant particle size distribution; this resulted in a new compression law. In this work, irregular particle shape is introduced, using 'clumps' (groups of spherical particles), allowing different relative densities of the same material to be subjected to normal compression. An investigation into the mechanics of yielding is presented, in which the onset of crushing is related to the average particle octahedral shear stress and 'yield' is seen to be a function of the available void space. Beyond yield, the normal compression lines for the clumps at different initial densities are examined and compared to that for spheres. The effects of coordination number and particle shape on the normal compression are studied, and in particular the micro mechanics behind the evolution of a fractal particle size distribution are revealed. (C) 2014 Elsevier B.V. All rights reserved.