混凝土结合了补充的水泥材料:压力强度的时间演变和环境生命周期评估
Noor Yaseen1,2, Stefany Alcivar-Bastidas3, Muhammad Irfan-Ul-Hassan1
1Department of Civil Engineering, University of Engineering and Technology, Lahore, Pakistan.
Heliyon
|February 9, 2024
概括
这项研究研究使用飞灰 (FA) 和烟 (SF) 作为混凝土中的水泥替代品. 这两种SCM都降低了全球变暖潜力 (GWP),SF显示早期的强度增长,FA显示后来的强度改善.
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.
- 环境科学 环境科学
背景情况:
- 越来越多的环境问题和与传统水泥生产相关的成本需要探索补充水泥材料 (SCM).
- 诸如飞灰 (FA) 和烟 (SF) 等工业废物为混凝土中的部分水泥替代提供了可持续的替代品.
- 研究对于了解SCM对混凝土性能和环境足迹的影响至关重要.
研究的目的:
- 为了评估不同百分比的FA和SF作为部分水泥替代品对混凝土的压力强度的影响.
- 开发和验证一个强度演变模型 (SEM) 来预测混凝土的时间强度发展.
- 评估与使用FA和SF相关的环境效益,特别是减少全球变暖潜力 (GWP).
主要方法:
- 分量二元混凝土混合物与FA (10%, 20%, 30%) 和SF (5%, 10%, 15%) 作为水泥替代品.
- 在早期 (3-28天) 和晚期 (56天) 进行压力强度测试.
- 开发一种使用非线性回归的强度进化模型 (SEM),并根据实验数据和fib Model Code 2010进行验证.
- 进行环境生命周期评估,以量化全球变暖潜力 (GWP) 的减少.
主要成果:
- 在FA混凝土中,没有早期的强度增加,但在20%的替换中,在56天后增长了4%.
- 在5%的替换过程中,SF混凝土在3天后增加了15%的强度,在10%的替换过程中,在56天后增加了2%的强度.
- 拟议的SEM与实验结果和fib Model Code 2010预测有很好的一致性.
- 使用FA (10-30%) 将GWP降低了9-29%,而SF (5-15%) 将GWP降低了5-14%.
结论:
- 用FA和SF部分替代水泥是可持续混凝土生产的可行策略.
- SF提供了早期的力量优势,而FA则有助于晚年力量的发展.
- 开发的SEM为预测混凝土强度演变提供了可靠的工具.
- 无论是FA还是SF都显著降低了混凝土的环境影响 (GWP),支持它们在绿色建筑中的使用.
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