Experimental measures of affine and nonaffine deformation in granular shear
Experimental measures of affine and nonaffine deformation in granular shear
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DOI：
10.1103/physrevlett.100.208302
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发表时间：
2008-05-23
影响因子：
8.6
通讯作者：
Behringer, R. P.
中科院分区：
文献类型：
--
作者：
Utter, Brian;Behringer, R. P.
通过二维粒状库埃特流实验，我们探讨了剪切下无序固体的失效和变形。剪切产生平均方位流、平滑仿射变形和不可逆的所谓非仿射粒子位移。我们发现这些过程的大小都相当，并且取决于局部剪切率。我们计算了表征非仿射运动的 Falk 和 Langer 参数 D-min(2)，并发现它可以用局部接近各向同性随机步骤 delta r(i) 的单粒子集合来很好地描述。单粒子非仿射位移的分布 delta r(i) 满足与 exp[-|delta r(i)/Delta r|(alpha)] 成比例的 P-1(delta r(i))（alpha 小于或类似于 2）。
Through 2D granular Couette flow experiments, we probe failure and deformation of disordered solids under shear. Shear produces a mean azimuthal flow, smooth affine deformations, and irreversible so-called nonaffine particle displacements. We find that these processes are all of comparable magnitude and depend on the local shear rate. We compute the parameter of Falk and Langer characterizing nonaffine motion, D-min(2), and find that it is reasonably well described in terms of collections of single particles making locally nearly isotropic random steps, delta r(i). Distributions for single particle nonaffine displacements, delta r(i), satisfy P-1(delta r(i)) proportional to exp[-|delta r(i)/Delta r|(alpha)] (alpha less than or similar to 2).