The effect of particle size distribution (PSD) of coral sands on the failure behavior of cemented coral sand specimens is investigated in this study. A series of static and impact loading tests on the specimens with various grain grading curves have been carried out. Test results show that the compression strength and impact resistance of the cemented coral sand specimen are increased with the increasing of the uniformity coefficient of coral sand particles. The specimen with a higher value of the uniformity coefficient would have a smaller failure angle under the same impact loads. In addition, the micro mechanism of PSD on the macroscale mechanical behavior is explored by a three-dimensional discrete element model. Four typical realistic particles are scanned and incorporated in the numerical models. The numerical model is established with the same PSD and impact loading conditions. Calibration tests are carried out to verify the numerical model. Then, a series of numerical analysis are conducted to examine the effects of particle shape and PSDs on the failure behavior. Analysis results indicate that the contact force distribution and absorbed energy can be linearly influenced by the PSDs. The realistic particles with a lower shape factor will result in a higher impact resistance. Thus, an optimum PSD can be design to meet the requirement of impact loadings. The outcome of this study could benefit for the foundation design with the consideration of the impact loadings.

本研究研究了珊瑚砂的粒径分布 (PSD) 对胶结珊瑚砂试样破坏行为的影响。对具有各种晶粒级配曲线的试样进行了一系列静态和冲击载荷试验。试验结果表明，胶结珊瑚砂试件的抗压强度和抗冲击性能随着珊瑚砂颗粒均匀系数的增加而增加。在相同的冲击载荷下，均匀系数值越高的试件，其破坏角越小。此外，PSD对宏观力学行为的微观机制通过三维离散元模型进行了探索。四个典型的现实粒子被扫描并纳入数值模型。数值模型建立在相同的PSD和冲击载荷条件下。进行校准测试以验证数值模型。然后，进行一系列数值分析以检查颗粒形状和 PSD 对失效行为的影响。分析结果表明接触力分布和吸收的能量可以线性地受到PSDs的影响。具有较低形状因子的逼真粒子将导致更高的抗冲击性。因此，可以设计最佳 PSD 以满足冲击载荷的要求。考虑到冲击载荷，这项研究的结果可能有益于基础设计。进行了一系列数值分析以检查颗粒形状和 PSD 对失效行为的影响。分析结果表明接触力分布和吸收的能量可以线性地受到PSDs的影响。具有较低形状因子的逼真粒子将导致更高的抗冲击性。因此，可以设计最佳 PSD 以满足冲击载荷的要求。考虑到冲击载荷，这项研究的结果可能有益于基础设计。进行了一系列数值分析以检查颗粒形状和 PSD 对失效行为的影响。分析结果表明接触力分布和吸收的能量可以线性地受到PSDs的影响。具有较低形状因子的逼真粒子将导致更高的抗冲击性。因此，可以设计最佳 PSD 以满足冲击载荷的要求。考虑到冲击载荷，这项研究的结果可能有益于基础设计。可以设计最佳 PSD 以满足冲击载荷的要求。考虑到冲击载荷，这项研究的结果可能有益于基础设计。可以设计最佳 PSD 以满足冲击载荷的要求。考虑到冲击载荷，这项研究的结果可能有益于基础设计。