强化水泥糊的MWCNT机械表征:实验和多尺度计算调查
Ioannis E Kavvadias1, Konstantinos Tsongas2, Kosmas E Bantilas1
1Department of Civil Engineering, Democritus University of Thrace, 67100 Xanthi, Greece.
Materials (Basel, Switzerland)
|August 12, 2023
概括
计算机建模准确地预测了用多壁碳纳米管 (MWCNTs) 增强的水泥糊的机械性能. 这种具有成本效益的方法指导了对工程应用中基于水泥的复合材料的优化.
科学领域:
- 材料科学 材料科学 材料科学
- 计算力学 计算力学 计算力学
- 土木工程 土木工程是指土木工程.
背景情况:
- 评估水泥纳米复合材料的非线性行为通常需要昂贵的实验方法.
- 多尺度计算方法为物质属性评估提供了具有成本效益的替代方案.
研究的目的:
- 开发和验证一个多尺度计算模型,用于预测多壁碳纳米管 (MWCNT) 增强水泥糊的机械性能.
- 研究MWCNTs对水泥纳米复合材料非线性构成性行为的影响.
主要方法:
- 开发一种随机顺序吸附算法,以生成3D代表体积元素 (RVEs).
- 在紧张和压缩下对RVE进行非线性有限元素分析 (FEA).
- 通过机械测试 (张力,压缩,三点曲) 和与FEA结果的比较进行实验验证.
主要成果:
- 多尺度模型准确地预测了Young的模量,压力和抗拉强度,与实验数据密切匹配.
- 观察到MWCNT度和改善的机械性能之间存在正相关性,这取决于理想的分散.
- 0.1%重量的MWCNTs/水泥糊复合物显示出数值和实验结果之间最好的一致性.
结论:
- 计算建模为评估水泥纳米复合材料的行为提供了一种可行且准确的方法.
- 该研究强调了MWCNT对材料性能的重大影响,以及考虑分散效应的重要性.
- 研究结果为优化工程应用中基于水泥的复合材料提供了宝贵的见解.
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