牛骨和大米灰对水泥砂机械和微观结构性质的协同作用
Bahiru Bewket Mitikie1, Teshome Anteneh Wubetie2, Walied A Elsaigh1
1Department of Civil and Environmental Engineering and Building Science, University of South Africa, Johannesburg, South Africa.
Scientific reports
|October 1, 2025
概括
本研究探讨使用牛骨灰和大米灰作为混凝土中的部分水泥替代品. 最佳的替代水平通过促进酸水合物凝的形成来提高压力强度和减少孔隙性.
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.
- 可持续建筑 可持续建筑
背景情况:
- 越来越多的水泥生产需要可持续的替代品.
- 农业和工业废物有潜力作为补充泥材料.
- 牛骨灰和大米灰是使用不足的废物.
研究的目的:
- 调查使用牛骨灰和大米灰作为砂中部分水泥替代品的可行性.
- 评估这些废料对水泥砂机械性能和耐久性的影响.
- 描述这些替代材料的结合引起的微观结构变化.
主要方法:
- 混凝土砂样本以0%,5%,10%,15%和20%的部分替代水泥量进行准备.
- 机械测试包括压力强度,超声波脉冲速度和水吸收.
- 通过硫酸盐攻击测试来评估耐用性.
- 微观结构和化学分析使用扫描电子显微镜 (SEM),热重力测量分析 (TGA),差异热分析 (DTA),里埃变换红外光谱 (FTIR),布鲁纳尔-埃梅特-泰勒 (BET) 表面积分析和酸盐分析.
主要成果:
- 压力强度在10%的替换 (28天) 时从31.5MPa增加到45.9MPa,在更高的替换水平时略有下降.
- 超声波脉冲速度和抗硫酸盐攻击能力有所改善.
- SEM分析显示,密度较高的矩阵增强了酸水合物 (C-S-H) 凝的形成.
- 在最佳灰含量样本中观察到 porousity 的减少.
结论:
- 用牛骨灰和大米灰的组合部分替换水泥可以提高水泥砂的机械性能和耐用性.
- 最佳的替代水平 (约10%) 促进了C-S-H凝的形成,从而减少了多孔性.
- 这些废物材料显示出可持续建筑应用的巨大潜力.
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