Initiating the motion of an object embedded in granular materials requires applying a force that exceeds a non-null threshold. This study focuses on how inter-granular adhesion affects this threshold. A series of 2D DEM numerical tests involving vertically pulling out plate-shape objects evidences a general linear scaling between the force threshold and the contact adhesion strength. We found that the slope of this relation is proportional to either the plate width or the plate depth, which ever is the largest. This reflects two regimes of mobility controlled by two distinct failure modes: (i) unsticking the plate from the grains underneath it or (ii) spliting a frustum of grains above the plate, which ever is the strongest.

启动嵌入颗粒材料中的物体的运动需要施加超过非零阈值的力。本研究侧重于颗粒间粘附如何影响该阈值。一系列涉及垂直拉出板状物体的 2D DEM 数值测试证明了力阈值和接触粘附强度之间的一般线性缩放。我们发现这种关系的斜率与板块宽度或板块深度成正比，以最大者为准。这反映了由两种不同的失效模式控制的两种流动状态：(i) 将板从其下方的颗粒上脱开或 (ii) 将板上方的颗粒平截头体分开，其中哪个是最强的。