膨胀剂对煤--灰基地质聚合物的特性和微观结构的影响
Qi Wang1,2,3, Mei Zhou1,2,3, Xinyi Wang1,2,3
1School of Civil Engineering, Liaoning Technical University, Fuxin 123000, China.
Materials (Basel, Switzerland)
|October 16, 2025
概括
将氧化 (CaO) 添加到煤泥飞灰地质聚合物 (CSFG) 中,可显著提高强度并减少收缩. 这种膨胀剂可增强地质聚合物特性,用于更好的建筑应用.
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.
- 地质聚合物化学 地质聚合物化学
背景情况:
- 煤炭,渣和飞灰是工业的副产品.
- 地质聚合物为普通波特兰水泥提供了可持续的替代品.
- 控制地质聚合物的特性,如设置时间和收缩,对于应用至关重要.
研究的目的:
- 调查扩张剂 (CaO,MgO,C4A3Š) 对基于煤,泥和飞灰的地质聚合物 (CSFG) 的影响.
- 分析对CSFG宏观性质 (定位时间,强度,收缩) 和微观结构的影响.
- 开发用于CSFG收缩的预测模型.
主要方法:
- 将膨胀剂 (CaO,MgO,C4A3Š) 纳入CSFG配方中.
- 宏观测试:设置时间,压力强度,干燥和自身收缩.
- 微结构分析:X射线衍射 (XRD),里埃变换红外光谱 (FTIR),扫描电子显微镜与能量分散光谱 (SEM-EDS),布鲁纳尔埃梅特泰勒 (BET) 分析.
主要成果:
- 7%的CaO添加减少了设置时间高达52.8%,增加了28天的强度12.6%,并减少了收缩高达43.5%.
- 3%的C4A3Š添加缩短了设置时间高达41.3%,28天强度提高了32.2%,但收缩率增加了高达58.3%.
- 过度的C4A3Š (>3%) 导致早期强度下降和微裂纹,这是由于迅速形成化石.
结论:
- 氧化 (CaO) 是最有效的扩张剂,可以改善CSFG的性能,平衡强度和收缩.
- 膨胀剂影响前体溶解和C-A-S-H凝,CaCO3和危险酶的形成.
- 对CSFG收缩的预测模型显示出很好的准确性,有助于材料设计和应用.
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