对木质生物质飞和F类飞作为砂中补充水泥材料的比较分析
Yaru Yang1, Koji Takasu2, Hiroki Suyama2
1Architecture Course, Graduate School of Environmental Engineering, The University of Kitakyushu, 1-1 Hibikino Wakamatsu, Kitakyushu 808-0135, Fukuoka, Japan.
Materials (Basel, Switzerland)
|August 10, 2024
概括
生物质飞灰 (BFA) 显示出作为可持续水泥替代品的潜力,在早期强度方面表现相当于煤炭飞灰 (CFA),并提供更好的长期变形性能. 对BFA的最佳使用是10-15%的替代率.
科学领域:
- 材料科学 材料科学 材料科学
- 可持续的建筑材料 可持续的建筑材料
- 绿色建筑技术 绿色建筑技术
背景情况:
- 生物质飞灰 (BFA) 为传统的水泥材料提供了一个可再生的替代品.
- 煤灰 (CFA) 是一种广泛使用的补充性水泥材料,但其可持续性有限.
- 在具体情况下使用BFA的经济和环境效益值得研究.
研究的目的:
- 为了评估生物质飞灰 (BFA) 作为可持续的水泥替代品.
- 为了比较BFA与F类飞灰 (CFA) 在水泥和砂中的性能.
- 为了确定BFA在水泥应用中的最佳替代率.
主要方法:
- 用BFA和CFA在10%至30%的替代水平上制备水泥糊和砂.
- 分析了反应性,水化产品 (CH和C-S-H),压力强度,微孔结构和干燥收缩.
- 评估了各种年龄的特性,包括7,28,91岁,以及最多182天的收缩时间.
主要成果:
- 在后期阶段,BFA对CFA表现出类似的pozzolanic反应性.
- 压缩强度随着BFA含量增加而下降,但早期强度 (例如,BFA-10与CFA-10) 类似.
- 与CFA-10相比,BFA-30在减少干燥收缩方面表现优越,具有更好的变形特性.
结论:
- 生物质飞灰 (BFA) 可以作为可持续的水泥替代品,而无需预处理.
- 在平衡性能和可持续性方面,BFA的最佳替换率被确定为10%至15%之间.
- 在提高混凝土混合物的环保性方面,BFA显得有前途.
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