在7岁时使用工业计算机断层扫描对自压缩混凝土的描述
Oana-Mihaela Banu1, Sergiu-Mihai Alexa-Stratulat1, Aliz-Eva Mathe2
1Faculty of Civil Engineering and Building Services, "Gheorghe Asachi" Technical University of Iasi, 700050 Iasi, Romania.
Materials (Basel, Switzerland)
|October 16, 2025
概括
自压缩混凝土 (SCC) 的孔隙结构显著影响其强度和弹性. 在7岁的SCC中,较高的总孔径和较大的孔径与机械性能下降相关,这是工业计算机断层扫描 (CT) 显示的.
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.
- 混凝土技术 混凝土技术
背景情况:
- 基于水泥的材料的孔隙结构,包括自压缩混凝土 (SCC),对于机械性能和耐用性至关重要.
- 诸如混合物设计,水结合比率,补充性水泥材料 (SCM) 或纳米材料等因素通过降低孔隙性来影响孔隙结构.
- 计算机断层扫描 (CT) 提供了一种非破坏性的方法来分析内部孔隙结构,提供精确的孔隙特征测量.
研究的目的:
- 在非常长的年龄 (7岁) 描述自压缩混凝土 (SCC) 的孔隙结构.
- 为了将内部孔隙结构与SCC的静态和动态弹性特性,压力强度和分裂拉伸强度相关联.
- 为了研究毛孔体积,最大毛孔直径和球状度对老化SCC的机械性能的影响.
主要方法:
- 使用工业计算机断层扫描 (CT),特别是尼康XTH 450CT扫描仪,用于大型混凝土样品的非破坏性分析.
- 评估了内部毛孔结构,包括毛孔体积,最大毛孔直径和球状性.
- 测量了7岁的SCC标本的静态和动态弹性特性,压力强度和裂纹抗拉强度.
主要成果:
- 在7岁时确定了孔隙结构参数与SCC的机械和弹性特性之间的相关性.
- 观察到,增加的毛孔总体积和最大毛孔直径会对SCC的强度和弹性产生负面影响.
- 发现总孔径对压力强度的影响比静态弹性模量更大.
结论:
- 内部孔隙结构,特别是孔隙体积和最大孔径,在很大程度上决定了自压缩混凝土的长期机械性能.
- 工业CT是一种有效的工具,用于在大型混凝土样本中进行详细的,非破坏性的孔状结构分析.
- 了解孔隙结构随时间的演变对于预测和提高混凝土结构的耐用性和机械完整性至关重要.
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