Natural granular materials such as sands often possess complex microstructural features including cleavage and minerals interfaces. Those features bring apparent mechanical anisotropy to particles and are known to have pronounced influence on particle crushing characteristics. This paper presents a multiscale simulation of continuous crushing of granular sand under one-dimensional compression in consideration of particle-scale anisotropy through modeling planes of weakness inside individual particles, with reference to granular materials rich in minerals and containing cleavages. The multiscale modeling is based on a coupled peridynamics and non-smooth contact dynamics method where peridynamics is used to model crushing of individual particles and non-smooth contact dynamics is employed to simulate discrete granular system. Weak microstructural planes are simulated by breaking a fraction of peridynamic bonds as an initial condition. Simulation results show that anisotropic particles containing weak planes result in larger number of fragments and exhibit relatively higher fractal dimension with respect to particle size. Particle shape is found to approach a steady state profile with continuous crushing. Anisotropic particles generally bear smaller sphericity, aspect ratio, elongation and flatness than those isotropic particles. The anisotropy in particles seems to mitigate shape effect on particle strength and crushing energy. Macromechanical yield stress of the sample is related to single particle strength monotonically, but the relationship appears to be nonlinear when different microstructural features are involved.

天然颗粒材料（例如沙子）通常具有复杂的微观结构特征，包括解理和矿物界面。这些特征给颗粒带来明显的机械各向异性，并且已知对颗粒破碎特性具有明显的影响。本文针对一维压缩下的连续砂粒破碎进行了多尺度模拟，其中考虑了通过模拟单个粒子内部弱点的平面来模拟粒子尺度的各向异性，并参考了富含矿物质和含解理作用的粒状材料。多尺度建模基于耦合的动力学和非光滑接触动力学方法，其中，动力学使用动力学模型对单个颗粒的破碎进行建模，非光滑接触动力学用于模拟离散的颗粒系统。通过破坏一部分蠕动键作为初始条件来模拟微结构面。仿真结果表明，包含弱平面的各向异性粒子会导致碎片数量增加，并且相对于粒度显示相对较高的分形维数。发现颗粒形状随着连续粉碎而接近稳态轮廓。各向异性颗粒通常具有比那些各向同性颗粒小的球形度，纵横比，伸长率和平坦度。颗粒中的各向异性似乎减轻了形状对颗粒强度和破碎能的影响。样品的宏观力学屈服应力与单颗粒强度单调相关，但是当涉及不同的微观结构特征时，该关系似乎是非线性的。