Particle shape is an important factor that affects particle breakage and the mechanical behaviour of granular materials. This report explored the effect of angularity on the mechanical behaviour of breakable granular materials under triaxial tests. Various angular particles are generated using the quasi-spherical polyhedron method. The angularity α is defined as the mean exterior angle of touching faces in a particle model. A breakable particle is constructed as an aggregate composed of coplanar and glued Voronoi polyhedra. After being prepared under the densest conditions, all assemblies were subjected to triaxial compression until a critical state was reached. The macroscopic characteristics, including the shear strength and dilatancy response, were investigated. Then, particle breakage characteristics, including the extent of particle breakage, breakage pattern and correlation between the particle breakage and energy input, were evaluated. Furthermore, the microscopic characteristics, including the contact force and fabric anisotropy, were examined to probe the microscopic origins of the shear strength. As α increases, the peak shear strength increases first and then remains constant, while the critical shear strength generally increases. Assemblies with larger angularity tend to cause more serious particle breakage. The relative breakage is linearly correlated with α under shear loading. Compared with unbreakable particles, the peak shear strength and the critical volumetric strain decline, and the degree of decline linearly increases with increasing α.

颗粒形状是影响颗粒破碎和颗粒材料力学行为的重要因素。本报告探讨了棱角对三轴试验下易碎颗粒材料力学行为的影响。使用准球形多面体方法生成各种有角度的粒子。角度α定义为粒子模型中接触面的平均外角。易碎粒子被构造为由共面和粘合的 Voronoi 多面体组成的聚集体。在最密集的条件下准备好后，所有组件都经过三轴压缩，直到达到临界状态。研究了宏观特性，包括剪切强度和剪胀响应。然后，评估颗粒破碎特性，包括颗粒破碎程度、破碎模式以及颗粒破碎与能量输入之间的相关性。此外，还检查了微观特性，包括接触力和织物各向异性，以探查剪切强度的微观起源。作为α增加，峰值剪切强度先增加然后保持不变，而临界剪切强度一般增加。具有较大角度的组件往往会导致更严重的颗粒破损。在剪切载荷下，相对断裂与α线性相关。与不易破碎的颗粒相比，峰值剪切强度和临界体积应变下降，下降程度随着α的增加而线性增加。