论文标题
干扰过渡附近的球体包装的结构和机械特性：从完全无定形到准排序结构
Structural and mechanical characteristics of sphere packings near the jamming transition: From fully amorphous to quasi-ordered structures
论文作者
论文摘要
机械稳定的球形包装是使用离散元素方法在三维空间中生成的，该方法的结构顺序范围很广，从完全无定形到准排序结构，其特征在于键取向顺序参数。随着包装压力，$ p $，与在堵塞过渡时（$ p \ 0 $）的边缘刚性极限（$ p \ gg 0 $）（$ p \ gg 0 $），$ z $，遵循压力熟悉的比例关系，即$Δz= z -z_c -z_c \ sim p^$ = 6 $ 2 $ 2 $ 2 $ 2} （$ d = 3 $是空间维度）。虽然以前已经注意到，$Δz$的确确实是确定包装属性的控制参数，但在这里我们显示包装结构在包装的机械性能上如何发挥影响力。具体来说，我们发现弹性（块$ k $和剪切$ g $）的模量通常称为$ m $，在$ m-m-m_c \ simΔz$的情况下成为$Δz$和结构的功能。在这里，$ m_c $是干扰过渡时弹性模量的值，取决于包装的结构。特别是，零剪切模量，$ g_c = 0 $，是完全无定形包装的特殊功能，而更多有序的包装则具有更大的正值，正值，$ g_c> 0 $。
Mechanically stable sphere packings are generated in three-dimensional space using the discrete element method, which span a wide range in structural order, ranging from fully amorphous to quasi-ordered structures, as characterized by the bond orientational order parameter. As the packing pressure, $p$, varies from the marginally rigid limit at the jamming transition ($p \approx 0$) to that of more robust systems ($p \gg 0$), the coordination number, $z$, follows a familiar scaling relation with pressure, namely, $Δz = z - z_c \sim p^{1/2}$, where $z_c = 2d = 6$ ($d=3$ is the spatial dimension). While it has previously been noted that $Δz$ does indeed remain the control parameter for determining the packing properties, here we show how the packing structure plays an influential role on the mechanical properties of the packings. Specifically, we find that the elastic (bulk $K$ and shear $G$) moduli, generically referred to as $M$, become functions of both $Δz$ and the structure, to the extent that $M-M_c \sim Δz$. Here, $M_c$ are values of the elastic moduli at the jamming transition, which depend on the structure of the packings. In particular, the zero shear modulus, $G_c=0$, is a special feature of fully amorphous packings, whereas more ordered packings take larger, positive values, $G_c > 0$.
