This study adopts the Smoothed Particle Hydrodynamics (SPH) technique to accurately and efficiently replicate and forecast the mesoscopic behavior of soil-rock mixtures (SRM). It introduces a novel approach for generating rock blocks within the SRM, utilizing a method that randomly selects angles and lengths. In addition, this research proposes a method for discretizing any shaped region into free particles with specific material attributes, named the regional medium particle discretization method. It incorporates the Drucker-Prager constitutive model to develop the SPH numerical model for SRM. Furthermore, it examines the effects of different rock sizes and rock contents on the SRM's failure characteristics and mechanical properties. The findings revealed that, for identical rock contents, smaller rock samples exhibit a more dispersed failure surface with numerous secondary shear bands, whereas larger rock samples display a smoother and more concentrated failure surface. As the rock content decreases, shear bands typically form in the sample's center and are relatively straight. However, as the rock content increases, the shear bands' configuration becomes more intricate, often featuring multiple shear bands. This method offers a fresh perspective for exploring the mechanical properties of heterogeneous materials.

中文翻译：

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基于SPH模型的土石混合体细观力学特性及破坏机理研究

本研究采用平滑粒子流体动力学（SPH）技术来准确有效地复制和预测土石混合物（SRM）的细观行为。它引入了一种在 SRM 内生成岩石块的新方法，利用随机选择角度和长度的方法。此外，本研究提出了一种将任意形状区域离散为具有特定材料属性的自由粒子的方法，称为区域介质粒子离散化方法。它结合了 Drucker-Prager 本构模型来开发 SRM 的 SPH 数值模型。此外，它还研究了不同岩石尺寸和岩石含量对 SRM 失效特征和机械性能的影响。研究结果表明，对于相同的岩石含量，较小的岩石样本表现出更分散的破坏面，并具有许多二次剪切带，而较大的岩石样本则表现出更平滑和更集中的破坏面。随着岩石含量的减少，剪切带通常在样品中心形成并且相对较直。然而，随着岩石含量的增加，剪切带的构造变得更加复杂，通常具有多个剪切带。该方法为探索异质材料的力学性能提供了新的视角。