关于化物结合及其在水泥材料中的硫酸盐释放的实验
Jian-Jun Dong1, Yu-Xiao Zou1, Xiao-Bao Zuo1
1School of Safety Science and Engineering, Nanjing University of Science & Technology, Nanjing 210094, China.
Materials (Basel, Switzerland)
|July 27, 2024
概括
暴露于硫酸盐会从水泥材料中释放物理结合的化物,而不是化学结合的化物. 较高的水与水泥比率和硫酸盐度加快了这种化物释放过程.
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:
- 化物进入是混凝土结构中钢筋腐蚀的主要原因.
- 了解化物结合和释放机制对于预测混凝土的耐用性至关重要.
- 硫酸盐攻击可以影响水泥基层内结合的化物的稳定性.
研究的目的:
- 实验性地研究硬化水泥糊颗粒 (HCP) 中的化物结合.
- 检查从HCP中硫酸盐诱导的结合化物的释放.
- 为了将化物结合和释放与材料特性和硫酸盐暴露条件相关联.
主要方法:
- 准备了各种水与水泥 (w/c) 比率 (0.35和0.45) 的硬化水泥糊颗粒 (HCP).
- 在化和随后的硫酸溶液中进行了长期浸泡试验.
- 银酸盐定位测量了自由化物度,而定量X射线衍射 (QXRD) 确定了结合含量.
主要成果:
- 具有较高w/c比率 (0.45) 的医疗人员表现出更大的化物结合能力.
- 结合的化物含量与弗里德尔盐和库泽尔盐的形成/分解有关.
- 硫酸盐容易从弗里德尔盐中释放化物,但不能完全从库泽尔盐中释放化物.
- 物理结合的化物比化学结合的化物更容易释放.
结论:
- 水与水泥的比率显著影响化物在水泥材料中的结合.
- 硫酸盐的存在会诱导结合化物的分化释放,主要影响弗里德尔盐.
- 物理结合的化物更容易受到硫酸盐诱导的释放,释放速度受到w/c比率和硫酸盐度的影响.
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