天然和合成石对基于水泥的材料的影响 水化和硬化国家财产
Giedrius Girskas1, Ina Pundienė1, Jolanta Pranckevičienė1
1Institute of Building Materials, Vilnius Gediminas Technical University, Linkmenų Str. 28, LT-10223 Vilnius, Lithuania.
Materials (Basel, Switzerland)
|August 26, 2023
概括
从废物中合成热石可以制造出可持续的建筑添加剂. 基于废弃物的AX热增强了水泥的水分,增加了28.6%的压力强度,并减少了水的吸收.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 可持续建筑 可持续建筑
背景情况:
- 石具有作为补充固材料的潜力.
- 用废物来合成热带石可以提高经济可行性和可持续性.
- 在建筑材料中加入热石可以提高性能并降低水泥消耗.
研究的目的:
- 调查合成化物,特别是废弃物衍生的AX化物的潜力,以增强水泥糊的水分.
- 评估用合成化物代替水泥对新鲜和硬化水泥糊的性能的影响.
- 为了比较基于废物的 AX 热带石与商业 4A 热带石和天然热带石的性能.
主要方法:
- 从废物中合成AX热石.
- 用高达10%的合成地质石 (基于废弃物的AX和商业4A) 替代水泥.
- 分析水泥糊的水化动力学 (热释放率),压力强度和吸水能力.
主要成果:
- 基于废弃物的AX热石的电导率明显高于商业4A和天然热石.
- 使用10% AX 热带石的水泥糊显示加速最大热释放率,48小时后总热量增加8.5%.
- 在28天后,添加AX硫酸增加了高达28.6%的压力强度,并减少了高达1.5%的吸水率.
结论:
- 新合成的基于废物的 AX 热氧化物是用于水泥材料的高性价比和高性能的添加剂.
- 亚氧化的特性,包括其Al/Na比率和电导率,对水泥水化和硬化糊的特性产生积极影响.
- 从废物中提取的热石代表了开发优质,干净和可持续的建筑材料的有希望的途径.
相关概念视频
01:24Hydration of Cement
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Hydration of cement is a chemical reaction between cement particles and water. This process occurs primarily through two mechanisms: through-solution and topochemical. In the through-solution process, anhydrous compounds dissolve into their constituents, hydrates form in the solution, and then precipitate from the supersaturated solution. The topochemical process involves solid-state reactions at the cement particle surface. The through-solution process dominates the topochemical process at the...
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01:29Strength and Heat of Hydration
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The hydration of cement is an exothermic reaction in which heat is generated as cement hydrates. This heat of hydration is critical to cement's strength development. The rate at which this heat is generated affects the temperature rise, with a majority of the heat being released early in the hydration process, half within the first three days, and about 75% within the first week.
The heat of hydration for each cement compound is significant; for instance, tricalcium aluminate (C3A) and...
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01:21Pozzolans
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Pozzolans are siliceous or aluminous materials blended with Portland cement. They interact with the calcium hydroxide produced during the hydration of Portland cement and contribute to improved strength and durability of concrete. The pozzolanic activity, a measure of a pozzolan's effectiveness, is typically assessed using the strength activity index, as defined in ASTM C 618-93, which calculates the ratio of the compressive strength of cement mixtures with and without pozzolan.
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01:20Curing of Concrete
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01:26Alkali Aggregate Reaction in Concrete
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01:28Transition Zone
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