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颗粒破碎对颗粒集合体的力学响应有着显著的影响。由于试验手段的限制,基于物理试验的颗粒破碎细观尺度的研究受到很大制约。离散元法为从不同尺度上研究颗粒破碎对颗粒集合体力学特性的影响提供了一条有效的方法。通过回顾国内外现有研究成果,介绍了基于离散元模拟颗粒破碎的两种方法,即基于颗粒黏结模型和基于碎片替换法的颗粒破碎模拟方法,论述了这两类方法的特点。基于颗粒黏结模型的颗粒破碎模拟方法破碎程度有限而且难以开展较大规模模拟计算,基于碎片替换法的颗粒破碎模拟方法需要考虑碎片替换模式和颗粒破碎准则这两个关键问题。整理并讨论了现有破碎模式中碎片颗粒的数目、尺寸分布、满足质量守恒定律的策略以及破碎的应力判定准则和力判定准则。提出了基于离散元的颗粒破碎模拟方法可能的研究方向。
Particle disintegration has a significant effect on the mechanical response of particle aggregates. Due to the limitations of experimental methods, the research on the microscopic scale of particle crushing based on physical experiments is greatly restricted. Discrete element method provides an effective method to study the effect of particle crushing on the mechanical properties of particle aggregates from different scales. By reviewing the existing research results both at home and abroad, two methods of particle crushing based on discrete element simulation are introduced, that is, the particle crushing simulation method based on particle bond model and the fragment replacement method, and the characteristics of these two methods are discussed. The particle crushing simulation method based on the particle cement model has a limited degree of crushing and is difficult to carry out large-scale simulation calculation. The particle crushing simulation method based on the fragment replacement method needs to consider two key issues: the debris replacement mode and the particle crushing criterion. The number and size distribution of debris particles in existing crushing mode, the strategy of satisfying the law of conservation of mass, and the judgment criteria of stress and force for crushing are summarized and discussed. A possible research direction of particle crushing simulation based on discrete element is proposed.