这座是飞灰建造的
Amy Montgomery1, Mahipal Kasaniya2, Pengfei Zhao1
1Department of Civil & Mineral Engineering, University of Toronto, Toronto, Ontario, Canada.
Journal of microscopy
|November 21, 2023
概括
混凝土中的飞灰显著阻止了和聚合物反应,这是混凝土退化的常见原因. 这项研究检查了Hungry Horse大的混凝土,揭示了飞灰.
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
- 地质地质地质地质地质地
背景情况:
- 饥饿的马大,建于1949年,是第一个在混凝土中使用燃煤飞灰的.
- 在Hungry Horse之前,北美大中Pozzolan水泥是常见的,但飞灰是新奇的.
- 的位置将其与煤炭发电的兴起和当前的气候变化问题联系起来.
研究的目的:
- 调查飞灰在抑制聚合物反应 (AAR) 的长期有效性.
- 通过显微镜比较来自Hungry Horse大的飞灰和没有飞灰的混凝土核心.
主要方法:
- 微观检查来自Hungry Horse大的两个混凝土核心.
- 一个核心含有燃煤飞灰;另一个没有.
- 分析的重点是砂岩粗聚合物和聚合物反应的迹象.
主要成果:
- 没有飞灰的混凝土核心显示了沙石聚合物中AAR的明显证据.
- 核心的砂岩聚合物与飞没有出现AAR的迹象.
- 对AAR的微观分析显示,酸凝填充了沙粒之间的空隙.
结论:
- 煤灰在长期内有效地抑制了混凝土中的-二氧化反应.
- 飞灰的存在可以防止有害的酸凝的形成.
- 这一发现凸显了在混凝土建筑中使用飞灰的耐久性好处.
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