颗粒大小分布不会影响颗粒材料的剩余切割强度:一个实验证明
Oscar Polanía1,2, Miguel Cabrera3, Mathieu Renouf2
1Department of Civil and Environmental Engineering, Universidad de los Andes, Bogotá, Colombia.
Physical review. E
|June 17, 2023
概括
颗粒材料的剩余摩擦角 (φr) 是独立于颗粒大小的多样性 (多分散性). 这项研究通过实验证实了数值发现,解决了材料科学和工程领域长期存在的争论.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 颗粒物质的物理 颗粒物质的物理
背景情况:
- 颗粒状材料表现出复杂的剪切行为,包括与余摩擦角 (φr) 相关的静止状态.
- 谷粒大小多样性或多分散性对φr的影响仍然是一个有争议的话题,数值模拟表明独立性,而实验证据不那么有说服力.
- 这场辩论影响了诸如土壤力学等领域,其中φr是一个关键的设计参数.
研究的目的:
- 实验性地研究多分散性对颗粒材料残余摩擦角度 (φr) 的影响.
- 为了协调数值模拟和实验观察关于多分散性和剪切强度之间的相互矛盾的发现.
- 为依赖 φr 进行设计的技术界提供更清晰的理解.
主要方法:
- 使用可控多分散性 (单分散,双分散和多分散) 的陶珠构建颗粒样本.
- 这些样品在三轴装置内切割,以测量切割应力和变形.
- 系统地改变参数,包括谷粒大小,尺寸跨度和谷粒大小分布,以评估它们对fr的影响.
主要成果:
- 实验结果表明,残余摩擦角 (φr) 独立于颗粒材料中的多分散度.
- 这一发现符合并证实了从数值模拟中获得的先前结果.
- 这项研究确立了颗粒大小特征与剪切强度行为之间的明确联系.
结论:
- 多分散性不会影响颗粒材料的余摩擦角 (φr),这与一些直觉相反,但与模拟相一致.
- 这种实验验证弥合了颗粒物材料力学理论/数值和实验理解之间的差距.
- 这些发现为工程师和研究人员在实际应用中使用φr提供了更大的信心.
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