飞灰含量对砂样本在干/湿硫酸盐攻击下耐久性的影响
Yage Zhang1, Dongge Wu2, Yushan Wang1
1College of Water Conservancy & Architectural Engineering, Shihezi University, Shihezi 832000, China.
Materials (Basel, Switzerland)
|January 11, 2024
概括
这项研究测试了新疆的水泥材料对硫酸盐攻击的耐用性. 更高的飞灰含量改善了蒸汽固化砂.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
背景情况:
- 在像新疆这样的恶劣环境中,水泥材料面临着耐用性挑战.
- 硫酸盐的攻击,特别是在干湿周期下,降低了混凝土的性能.
- 飞是一种常见的补充水泥材料,具有潜在的耐久性好处.
研究的目的:
- 在模拟的新疆环境条件下,评估各种飞灰含量的水泥材料的耐用性.
- 分析干/湿硫酸盐攻击对飞灰砂机械性能和微观结构的影响.
- 建立硫酸盐攻击下砂的强度演变模型,阐明飞灰在增强耐力方面的作用.
主要方法:
- 准备了具有不同飞灰含量的砂样本,并经过循环干/湿硫酸盐攻击.
- 使用了标准和蒸汽固化在70°C的温度.
- 耐久性通过外观损失,曲和压力强度测试来评估.
- 使用X射线衍射 (XRD) 和扫描电子显微镜 (SEM) 进行微观结构和组成分析.
主要成果:
- 在160个侵蚀周期后,随着飞灰含量增加,屈曲强度下降.
- 蒸汽固化样本含有45%的飞灰,在整个侵蚀过程中显示出最高的相对压力强度.
- 开发的强度演变模型与实验数据有很好的一致性 (R2 ≥0.879).
- 飞灰与硫酸盐和氧化的波佐兰反应增强了对侵蚀的抵抗力.
- 石膏成为主要的侵蚀产品,其飞含量增加.
结论:
- 飞灰含量显著影响了水泥材料对硫酸盐攻击的抵抗力.
- 蒸汽固化在干燥/湿硫酸盐条件下提高了飞灰砂的耐用性.
- 飞灰的pozzolanic活动在减轻硫酸盐诱导的降解方面发挥着至关重要的作用.
- 建立的强度演变模型为预测砂性能提供了有价值的工具.
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