关于混凝土的化物结合能力的研究,该混凝土含有额外的固材料
Heba Abd El-Fattah1, Yehia Abd El-Zaher2, Mohamed Kohail2
1Structural Engineering Department, Faculty of Engineering, Ain Shams University, Cairo, Egypt. heba.abdelfattah.94@eng.asu.edu.eg.
Scientific reports
|June 5, 2024
概括
像GGBFS这样的补充水泥材料 (SCM) 增强了混凝土的性能.
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.
- 腐蚀科学 腐蚀科学
背景情况:
- 化物诱导的腐蚀是钢筋混凝土退化的主要原因.
- 在混凝土中结合自由化物离子对于减轻钢筋腐蚀至关重要.
- 混凝土的化物结合能力受其水泥系统组成的影响.
研究的目的:
- 调查混凝土的化物结合能力,其中包括各种补充性水泥材料 (SCM).
- 评估SCM对与化物结合相关的混凝土性能的影响.
- 评估SCM,如地面颗粒高炉渣 (GGBFS),飞灰和金属作为普通波特兰水泥 (OPC) 的部分替代品.
主要方法:
- 准备了部分用SCM取代OPC的混凝土样本.
- 使用半细胞潜力,加速腐蚀测试,压力强度,快速透,吸附性,pH测量和X射线衍射 (XRD) 评估化物结合能力和混凝土性能.
- GGBFS,飞灰和甲的性能比较.
主要成果:
- 使用SCM显著提高了混凝土的化物结合能力.
- 含有高酸盐和含量的SCM,如GGBFS,显示出更强的化物结合.
- SCM 改善了与耐用性和化物耐受性相关的各种混凝土性能.
结论:
- SCM有效地提高了混凝土结合化物离子的能力,降低了腐蚀风险.
- SCM的类型和数量,特别是GGBFS,是增强化物结合的关键因素.
- 建筑规范中的当前化物含量限制值可能需要修订,以考虑到SCM的有益结合能力.
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