封闭形式模型的应用,用于分析近脆材料的断裂
Xiangyu Han1, Peng Li2, Jianguo Liu2
1School of Civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, China.
Materials (Basel, Switzerland)
|January 23, 2024
概括
边界效应模型 (BEM) 准确地预测了准脆材料中的断裂特性,揭示了尺寸独立的材料常数. 该模型增强了对工程材料中断裂力学的理解和应用.
科学领域:
- 材料科学 材料科学 材料科学
- 断裂力学 断裂力学 断裂力学
- 工程材料 工程材料
背景情况:
- 准脆性材料的断裂故障带来了重大的工程挑战.
- 了解尺寸对断裂特性的影响对于材料设计和结构完整性至关重要.
- 现有的模型可能无法完全捕捉到各种准脆材料中断裂行为的复杂性.
研究的目的:
- 彻底研究边界效应模型 (BEM) 用于预测准脆材料的断裂特性.
- 阐明BEM的概念框架,进化过程和适用范围.
- 建立BEM作为可靠的工具来确定尺寸独立的断裂特性.
主要方法:
- 将边界效应模型 (BEM) 与各种断裂测试 (三点曲,四点曲,形分裂) 的整合.
- 对线性和非线性BEM方法进行骨折行为预测的分析.
- 验证使用140个断裂测试结果从混凝土,硬岩石和竹子磨机.
主要成果:
- BEM准确地计算了不同准易碎材料的断裂特性.
- 在最大故障负载和材料断裂特性之间建立了线性相关性.
- 通过BEM确定的断裂特性被发现是一致的材料常数,无论样品大小,隙长度,几何或微观结构如何.
结论:
- 边界效应模型 (BEM) 提供了一种强大而可靠的方法来评估准脆材料的断裂特性.
- 对于材料设计和工程应用而言,BEM识别尺寸独立材料常数的能力具有重大实际意义.
- 非线性和线性BEM分析的协同作用为预测断裂行为提供了一个强大的方法.
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