聚合物混凝土动态特性中等尺度建模
1Department of Mechanical Engineering and Mechatronics, West Pomeranian University of Technology in Szczecin, al. Piastów 19, 70-310 Szczecin, Poland.
Polymers
|November 14, 2023
概括
预测复合材料的动态特性至关重要. 介面尺度有限元建模与亚结构识别准确地建模了聚合物混凝土,包括界面过渡区 (ITZ) 的阻尼效应.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算力学 计算力学 计算力学
背景情况:
- 在设计阶段,准确预测复合材料的动态特性至关重要.
- 中等尺度有限元建模为模拟这些属性提供了一种强大的方法.
- 聚合物混凝土是一种广泛使用的复合材料,需要详细的建模来预测性能.
研究的目的:
- 为预测聚合物混凝土的动态性质提出一个大尺度建模方法.
- 使用亚结构识别,一种模型更新技术,以提高准确性.
- 调查不同组件,包括界面过渡区 (ITZ) 对整体动态行为的贡献.
主要方法:
- 使用有限元建模 (FEM) 来构建一个聚合物混凝土梁的中等尺度模型.
- 该模型被解为子结构:聚合物矩阵,聚合物和界面过渡区 (ITZ).
- 基于频率响应函数的子结构识别被用于代模型更新和参数确定,包括阻尼.
主要成果:
- 介面尺度有限元素模型成功预测了聚合物混凝土梁的动态特性.
- 亚结构识别使得能够准确地确定像ITZ这样的亚结构的参数,这些亚结构不能被隔离.
- 该方法量化了ITZ对复合结构的缓冲贡献.
结论:
- 与亚结构识别相结合的mesoscale有限元素建模是预测聚合物混凝土动态性质的有效方法.
- 这种方法准确地解释了阻尼效应,特别是来自界面过渡区的阻尼效应.
- 该研究强调了亚结构识别能够模拟复杂的复合行为,并确定不可隔离组件的参数的能力.
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