在不同固化温度下,活性飞灰砂中CaO的影响
David Murillo-Silo1, Enrique Fernández-Ledesma2, José Ramón Jiménez2
1Área de Explotación de Minas, Universidad de Córdoba, E.P.S de Belmez, Avenida de la Universidad s/n, Belmez, E-14240 Córdoba, Spain.
Materials (Basel, Switzerland)
|September 27, 2025
概括
将氧化 (CaO) 添加到活性飞灰砂 (AAFM) 中可以提高机械性能,并允许更早的拆塑. 然而,它并不能完全取代在这些应用中需要热固化.
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:
- 活性飞灰砂 (AAFM) 为传统的波特兰水泥混凝土提供了一个可持续的替代方案.
- 传统的AAFM热固化需要大量的能量,这推动了对替代固化方法的研究.
- 氧化 (CaO) 被探索为一种潜在的添加剂,以修改AAFM属性并减少固化能量.
研究的目的:
- 调查用CaO部分替代飞对AAFM性能的影响.
- 评估CaO在热和环境固化条件下对机械性能的影响.
- 评估CaO降低或取代AAFM常规热固化的潜力.
主要方法:
- 用0%,2%和4%的CaO替代飞灰制备AAFM.
- 固化方案包括热固化 (70°C24小时) 和环境固化 (21°C24小时).
- 使用XRD,XRF,TGA/DTA,SEM,颗粒大小分析和机械测试 (压缩/屈曲强度,密度,多孔性) 在7,14和28天进行表征.
主要成果:
- 添加CaO提高了机械性能 (在热固化下,压力强度高达13.8%,4%的CaO) 并在两个固化环境中加快了设置.
- 观察到酸盐 (C-S-H) 和-酸盐 (C-A-S-H) 凝的形成,包括玛格丽特,与CaO合并.
- 与热固化样本中更密集,层层的形态相比,环境固化的砂具有更高的孔隙性和更不紧的微观结构.
结论:
- 氧化作为飞灰的有效部分替代品,增强AAFM的机械性能,并使早期拆塑成为可能.
- 虽然有益,但研究的CaO百分比不能完全消除需要热固化以获得最佳性能.
- 建议进一步研究较高的CaO含量,设置延迟器或用于节能AAFM的替代固化策略.
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