用离散元件方法模拟在拉伸应力下混凝土中中等尺度破裂过程
Zhenyu Zhu1, Bintang Mas Mediamartha1, Shuyang Yu1
1School of Transportation and Civil Engineering, Nantong University, Nantong 226019, China.
Materials (Basel, Switzerland)
|July 12, 2025
概括
这项研究使用离散元件方法 (DEM) 模拟来模拟混凝土破裂. 它量化了聚合物和孔隙百分比如何影响拉伸强度,为材料设计提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 计算力学 计算力学 计算力学
背景情况:
- 由于其复杂的多相异质结构,在拉力负荷下对混凝土的中镜损伤的特征具有挑战性.
- 传统的方法很难解决混凝土中镜裂变行为的复杂细节.
- 了解微结构特征对拉伸性能的影响对于材料优化至关重要.
研究的目的:
- 为了解决在拉伸负荷下特征混凝土中镜损伤演变的局限性.
- 使用PFC2D的离散元件方法 (DEM) 建模混凝土的中观裂纹,并结合关键的微观结构组件.
- 研究聚合物和孔隙百分比对裂传播和拉伸强度的定量影响.
主要方法:
- 采用离散元件方法 (DEM) 与PFC2D软件进行混凝土的中光学建模.
- 集成现实的微观结构元素:聚合物,砂,界面过渡区 (ITZ) 和孔隙.
- 对单轴拉伸负荷场景的实验数据进行校准的模拟参数.
主要成果:
- 模拟显示,从30%增加到40%的总体百分比,使得峰值抗拉强度降低了26%,随后恢复到45%.
- 透度从2%增加到4%将峰值强度降低约3%,进一步降至6%,导致14%的减少.
- DEM模拟结果与实验数据密切一致,验证了模型的有效性.
结论:
- 离散元件方法 (DEM) 是一种有效的工具,用于模拟混凝土中中观裂变.
- 微结构参数,如聚合物和孔隙百分比,显著影响混凝土的拉伸性能.
- 这项研究为优化混凝土拉伸性能提供了中视镜理论基础,并强调了模拟中现实的中视镜特征的重要性.
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