The particle shape contributes significantly to sand mechanical properties but is difficult to study in laboratory experiments. In this study, microscopy experiments were used to classify sand particle morphologies as spherical, non-spherical and ball-shaped. Particles with these three morphologies were modeled using the discrete element method to analyze the effect of the particle shape on the shear strength in a direct shear test simulation. The simulation results showed that the non-spherical particles and balls exhibited the highest and lowest peak shear strengths, respectively, under a low vertical stress. The highest and lowest contact force numbers were observed for the non-spherical particles and balls, respectively. The sand particles exhibited a higher resistance to motion with increasing contact force numbers, resulting in a higher shear strength. For particles with low sphericity (S) and roundness (R) values, a high number of contacts and interlocking structures can form, increasing resistance to external forces. As the S decreased, the anisotropy in the contact force increased during the test, and the contact number distribution of the spherical particles tended to remain isotropic during the entire process.

颗粒形状对砂的机械性能有很大贡献，但是很难在实验室实验中研究。在这项研究中，使用显微镜实验将砂粒形态分类为球形，非球形和球形。使用离散元素方法对具有这三种形态的颗粒进行建模，以在直接剪切试验模拟中分析颗粒形状对剪切强度的影响。仿真结果表明，在低垂直应力下，非球形颗粒和球体分别表现出最高和最低的峰值剪切强度。对于非球形颗粒和球，分别观察到最高和最低的接触力数。随着接触力数的增加，砂粒表现出较高的运动阻力，导致更高的剪切强度。对于具有低球度（S）和圆度（R）值的粒子，可以形成大量的接触和互锁结构，从而增加了对外力的抵抗力。随着S的降低，在测试过程中接触力的各向异性增加，并且球形颗粒的接触数分布在整个过程中趋于保持各向同性。