Modeling the single particle crushing behavior by random discrete element method
Modeling the single particle crushing behavior by random discrete element method
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DOI：
10.1016/j.conbuildmat.2023.134519
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发表时间：
2024-01
影响因子：
7.4
通讯作者：
Du-min Kuang;Zhi-lin Long;Tao Zhao;Biao Luo;I. Ogwu;Feng-lan Kuang
中科院分区：
文献类型：
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作者：
Du-min Kuang;Zhi-lin Long;Tao Zhao;Biao Luo;I. Ogwu;Feng-lan Kuang
颗粒材料的微观性质通常表现出显著的不均匀性。真实的颗粒破碎模拟在粒状材料中需要使用的模型，包括其微观特性的空间异质性。本研究引入一种新的方法，随机场理论-离散元法（RFT-DEM）模型，模拟颗粒材料的单颗粒破碎行为，考虑到颗粒内部的微观特性的空间异质性。通过随机场理论表征了材料的非均匀性，表明模拟结果与实验结果之间具有合理的一致性。通过一系列的单颗粒破碎模拟的破碎强度和威布尔模量的尺寸依赖性的特性进行了确认，强调该模型的能力，以捕捉这些功能。系统分析了变异系数（COV）和波动尺度（SOF）对单颗粒破碎行为的影响。增加COV导致降低的特征抗压强度和Weibull模量，较大的颗粒表现出更大的敏感性。此外，增加SOF最初增加这些参数，直到阈值SOF值为0.0005米，超过该阈值，它们稳定。降低COV或增加SOF减小了特征抗压强度中的尺寸效应，并且一旦COV超过0.03的阈值，尺寸效应变得与其变化无关。这些发现有助于全面了解颗粒材料的微观特性和破碎行为之间错综复杂的相互作用。
Microscopic properties of granular materials typically exhibit significant heterogeneity. Realistic particle crushing simulation in granular materials requires the use of model that incorporate the spatial heterogeneity of its microscopic properties. This study introduces a novel approach, the Random Field Theory-Discrete Element Method (RFT-DEM) model, to simulate the single-particle crushing behavior of granular materials, considering the spatial heterogeneity of microscopic properties within particles. The material heterogeneity was characterized through Random Field Theory, demonstrating reasonable consistency between simulated and experimental results. The size-dependent characteristics of crushing strength and Weibull modulus were confirmed through a series of single-particle crushing simulations, emphasizing the model's capability to capture such features. Systematic analyses explored the impact of coefficient of variation (COV) and scale of fluctuation (SOF) on single-particle crushing behavior. Increasing COV resulted in reduced characteristic crushing strength and Weibull modulus, with larger particles exhibiting greater sensitivity. Furthermore, increasing SOF initially increased these parameters until a threshold SOF value of 0.0005 m, beyond which they stabilized. Reduced COV or increased SOF diminished the size effect in characteristic crushing strength, and once COV exceeded a threshold of 0.03, the size effect became independent of its variations. These findings contribute to a comprehensive understanding of the intricate interplay between microscopic properties and crushing behavior in granular materials.