快速评估砂和混凝土中的硫酸盐阻力
Seyedsaleh Mousavinezhad1, William K Toledo2, Craig M Newtson1
1Department of Civil Engineering, New Mexico State University, Las Cruces, NM 88003, USA.
Materials (Basel, Switzerland)
|October 16, 2024
概括
加速测试方法显著减少了70%的混凝土硫酸盐耐受性评估时间. 作为一种可持续的替代品,metakaolin增强了混凝土混合物的硫酸盐耐受性,提供了更好的耐用性.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 建筑的耐用性 建筑的耐用性
背景情况:
- 硫酸盐攻击是混凝土结构的主要耐久性问题.
- 传统的硫酸盐耐受性测试 (ASTM C1012) 是耗时的,并且仅限于砂.
- 随着F类飞灰的可用性下降,需要探索可持续的替代品.
研究的目的:
- 开发和验证加速测试方法,用于评估混凝土和砂混合物的硫酸盐耐受性.
- 确定有效和可持续的补充水泥材料 (SCM) 作为飞灰的替代品.
- 建立解释加快硫酸盐耐药性测试结果的标准.
主要方法:
- 通过并完善了对砂和混凝土中硫酸盐耐受性的加速测试协议.
- 评估了14种砂和4种混凝土混合物,其中包括I型和I/II型波特兰水泥以及各种SCM.
- 开发了加速测试结果的解释标准,并将其与标准方法进行比较 (ASTM C1012,ACI 318-19).
主要成果:
- 加速方法将测试时间减少了70% (砂21天,混凝土56天).
- 甲可林显著改善了砂和混凝土的硫酸盐耐受性.
- 烟和天然波佐兰对硫酸盐耐药性的影响有限.
- 15%的金属与I/II型水泥产生了最佳的硫酸盐耐受性.
结论:
- 加速测试提供了快速可靠的评估混凝土的硫酸盐耐受性.
- 甲甲是一种有前途的可持续性SCM,用于增强混凝土对硫酸盐攻击的耐用性.
- 开发的解释标准与既定标准保持一致,使得材料选择更快.
关键词:
加速测试方法的加速测试方法.混凝土混凝土混凝土是什么甲基可林 (metacaolin) 是一种可的化合物.迫击炮迫击炮迫击炮天然的波佐兰 (pozzolan) 是一种天然的波佐兰.硫酸盐攻击攻击更多相关视频
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