生态高效的纤维增强混凝土:从混合设计到新鲜和硬化的状态行为
Ana Bergmann1, Mohammed Nabil Eid1, Mayra T de Grazia1
1Department of Civil Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
Materials (Basel, Switzerland)
|March 27, 2025
概括
颗粒包装模型 (PPMs) 创建可持续的,低水泥纤维增强混凝土 (FRC) 减少了波特兰水泥 (PC) 含量. 这些生态效的FRC混合物表现出增强的新鲜和硬化性能,提高了建筑的可持续性.
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.
- 可持续的建筑材料 可持续的建筑材料
背景情况:
- 传统的纤维增强混凝土 (FRC) 混合物往往需要高波特兰水泥 (PC) 含量或化学添加剂,阻碍可持续发展目标.
- 为了在生态效率高的FRC中达到理想的新鲜和硬化性能,需要先进的混合物设计技术.
研究的目的:
- 使用颗粒包装模型 (PPM) 进行生态效,低水泥 (LC) FRC混合物的比例.
- 评估用PPM设计的LC FRC混合物的新鲜和硬化状态特性.
- 为了减少FRC中的水泥含量,同时保持或提高性能.
主要方法:
- 设计了12个LC FRC混合物,PC含量降低 (<300公斤/米3),包含石灰石填充剂 (LF).
- 使用了两种纤维类型 (聚烯和钢),含量和长度各不相同.
- 使用的PPM具有两个分布系数 (q-因子:0.21和0.26) 用于混合物比例.
- 评估的新鲜性质 (VeBe时间,沉降,质) 和硬化性质 (压力强度,曲性能).
主要成果:
- 与传统混合物相比,PPM设计的FRC混合物达到高达70%的压力强度和64%的曲能力.
- 尽管使用的水泥减少了20%,但PPM混合物显示了更高的包装密度,由更高的VeBe时间和产量压力表明.
- PPM混合物表现出剪切稀释行为,适合用于送或振动等实际应用.
结论:
- PPM 能够开发出生态效率高,低度的 FRC 混合物.
- 这些混合物提供了可比或优越的硬化性能,同时减少了对环境的影响.
- 像PPM这样的先进混合物设计技术对于可持续建筑材料至关重要.
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