关于在预混合高度离子下在水泥糊中化物的机械性能和结合行为的研究
Aiqin Wang1,2, Xixian Du1,2, Gang Li1,2
1College of Water Conservancy & Architectural Engineering, Shihezi University, Shihezi 832000, China.
Materials (Basel, Switzerland)
|October 16, 2025
概括
将5%的化物 (Cl-) 添加到水泥糊中可以提高压力强度和化物结合. 然而,过量的化物会损害机械性能,这凸显了化物含量对混凝土耐用性的重要性.
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.
- 腐蚀科学 腐蚀科学
背景情况:
- 化物进入混凝土结构会导致钢筋腐蚀,损害结构完整性和耐用性.
- 提高水泥材料的化物结合能力对于减轻腐蚀损伤至关重要.
- 了解各种因素对化物结合的影响对于开发耐用混凝土至关重要.
研究的目的:
- 调查水与水泥比率 (W/C),固化年龄和预混合化物 (Cl-) 度对水泥糊的压力强度和化物结合的影响.
- 为了确定最佳的预混合化物度,以提高机械性能和结合能力.
- 阐明水泥糊中化物结合的机制,包括C-S-H和弗里德尔盐 (Fs) 的作用.
主要方法:
- 用不同的W/C比率,固化年龄和预混合化物度制备水泥糊样本.
- 随着时间的推移,压力强度发展的评估.
- 使用化学分析量化总和结合的化物含量.
- 对涉及C-S-H和Fs的化物结合机制的分析.
主要成果:
- 预混合的化物度为5%,增强了压力强度和化物结合能力.
- 过度的化物度 (>5%) 对机械性能产生负面影响.
- 总含量显著影响结合能力,在5%预混合度 (在2%总Cl-范围内) 观察到最佳结合.
- 化物的C-S-H吸附与含量增加,而与Fs结合的比例最初下降,然后稳定.
- 5%的预混合度被确定为水泥糊的安全极限,但钢筋混凝土中的自由化物需要仔细考虑.
结论:
- 优化预混合化物度是提高水泥糊压力强度和化物结合的关键.
- 总含量是一个关键参数,它决定了水泥材料的结合效率.
- 虽然C-S-H在化物吸附中起着重要作用,但Fs的贡献因化物水平而异.
- 这些发现为改善钢筋混凝土结构耐用性的化物管理策略提供了洞察力.
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