The anisotropy of rockfill materials has a significant influence on the performance of engineering structures. However, relevant research data are very limited, because of the difficulty with preparing specimens with different inclination angles using traditional methods. Furthermore, the anisotropy test of rockfill materials is complex and complicated, especially for triaxial tests, in which the major principal stress plane intersects with the compaction plane at different angles. In this study, the geometric characteristics of a typical particle fraction consisting of a specific rockfill material were statistically investigated, and the distribution characteristics of particle orientation in specimens prepared via different compaction methods were examined. For high-density rockfill materials, a set of specimen preparation devices for inclined compaction planes was developed, and a series of conventional triaxial compression tests with different principal stress direction angles were conducted. The results reveal that the principal stress direction angle has a significant effect on the modulus, shear strength, and dilatancy of the compacted rockfill materials. Analysis of the relationship between the principal stress direction angles, change in the stress state, and change in the corresponding dominant shear plane shows that the angle between the compacted surface and dominant shear plane is closely related to interlocking resistance associated with the particle orientation. In addition, different principal stress direction angles can change the extent of the particle interlocking effect, causing the specimen to exhibit different degrees of anisotropy.

堆石料的各向异性对工程结构的性能有很大的影响。然而，由于使用传统方法难以制备具有不同倾角的样品，相关的研究数据非常有限。此外，堆石料的各向异性试验是复杂而复杂的，特别是对于三轴试验，在该试验中，主要主应力平面与压实平面以不同的角度相交。在这项研究中，统计研究了由特定堆石材料组成的典型颗粒级分的几何特征，并研究了通过不同压实方法制备的试样中颗粒取向的分布特征。对于高密度堆石料，开发了一套用于倾斜压实平面的试样制备装置，并进行了一系列具有不同主应力方向角的常规三轴压缩试验。结果表明，主应力方向角对压实堆石材料的模量，抗剪强度和膨胀率有显着影响。分析主应力方向角，应力状态的变化以及相应的主剪切平面的变化之间的关系，可以发现，压实表面与主剪切平面之间的角度与与颗粒取向相关的互锁阻力密切相关。此外，不同的主应力方向角可以改变粒子互锁效果的程度，