暴露于高温和随后的再水化后的水泥糊的微观机械性能和物理化学变化
Lei Xu1,2, Xiaochuan Hu3, Ruifeng Tang1
1Beijing Building Materials Academy of Sciences Research, Beijing 100041, China.
Materials (Basel, Switzerland)
|March 13, 2025
概括
研究水泥糊的高温表明,虽然适度的热量 (300-600°C),然后再加水,可以提高微硬度,但极高的热量 (900°C) 会造成损伤. 较高的水泥等级和含水量提高了耐热性.
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.
- 地质化学 地质化学
背景情况:
- 了解水泥材料在热应力下的行为对于基础设施的耐用性至关重要.
- 高温可以显著改变水泥的微观结构和机械性能.
研究的目的:
- 为了研究高温 (300°C,600°C,900°C) 和随后的再水对水泥质性能的影响.
- 分析不同水泥等级和水-水泥比率的微观机械性能和物理化学特征的变化.
主要方法:
- 维克斯微硬度测试 维克斯微硬度测试
- 在X射线衍射 (XRD) 中.
- 热重力测量 (TGA) 是一种测量方法.
- 质子核磁共振 (H NMR) 光谱学.
主要成果:
- 更高的水泥等级 (CEM I 52.5) 和水与水泥的比率 (0.4) 显示出对高温的优越抵抗力.
- 加热改变了C-S-H凝结构,增加了孔隙性. 在300°C和600°C加热后再加水增加了微硬度.
- 900°C的温度导致了微机械性能的降解. 在加热至600°C后,由于内索酸盐阶段的再化,观察到显著的物质恢复.
结论:
- 适度加热 (300-600°C),然后再加水,可以提高水泥糊的微硬度,600°C显示出更好的回收.
- 过高的温度 (900°C) 损害了水泥糊的机械完整性.
- 水泥糊的成分会影响其耐热性和加热后恢复潜力.
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