在高温下飞灰热层混凝土的影响
Kowsalya Mahendra Kumar1, Sindhu Nachiar Siva Subramanian2, Anandh Sekar1
1Department of Civil Engineering, SRM Institute of Science and Technology, Kattankulathur, 603203, India.
Environmental science and pollution research international
|September 11, 2025
概括
这项研究研究了用飞灰和阿尔科芬修饰的混凝土,发现它提供了对高温的增强抵抗力. 这些添加物提高了热稳定性,加密了混凝土.
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.
- 消防安全工程 消防安全工程
背景情况:
- 在建筑物发生火灾时,高温会影响混凝土的结构完整性.
- 材料特性显著影响混凝土在热应力下的性能.
研究的目的:
- 为了评估混凝土的高温性能,使用飞灰热层作为精细聚合物和阿尔科芬作为粘合剂.
- 分析这些替代物对混凝土热物理,机械和微观结构性质的影响.
主要方法:
- 准备了三种混凝土混合比,并将它们暴露在200至800°C的温度中,持续1-3小时.
- 实验分析包括热物理评估,体重减轻,孔隙结构分析,剩余压力强度和故障模式观察.
- 使用扫描电子显微镜 (SEM),X射线衍射 (XRD) 和富里埃变换红外光谱 (FTIR) 检查化学恶化.
主要成果:
- 在对照混凝土 (CC) 中,残余压力强度显著下降,但在飞灰热层和阿尔科芬修饰混凝土 (FACC和FACCAF) 中,减少较小.
- 在热暴露后,FACC和FACCAF混合物表现出较低的强度损失 (分别为18.1334.33%和17.9829.64%) 与CC (53.1872.50%) 相比.
- 微结构分析表明,添加飞灰层和阿尔科芬,通过加密混凝土矩阵和孔隙结构,提高了耐热性.
结论:
- 添加飞灰热层和阿尔科芬增加了混凝土对高温的抵抗力.
- 这些材料通过在混凝土基质中管理热能并完善其孔隙结构,从而有助于热稳定.
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