酸和PCE可塑剂的联合使用对二元OPC-CAC结合剂的微观结构和性能的影响
Victoria Shvetsova1, Vadim Soloviev1, Evgenii Matiushin1
1Department of Building Materials Science, National Research Moscow State University of Civil Engineering (NRU MSUCE), Yaroslavskoe Shosse, 26, 129337 Moscow, Russia.
Materials (Basel, Switzerland)
|December 17, 2024
概括
酸显著影响水化和水泥强度. 它加速混合水泥的早期强度发展和热演变,同时改变关键水泥化合物的相位组成和水化动力学.
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.
- 化学工程是化学工程的重要组成部分.
背景情况:
- 与波特兰水泥和酸水泥混合的粘合剂表现出快速的水化和高热演变.
- 了解对水泥材料的添加效应对于性能优化至关重要.
- 酸作为一种添加剂,用于修改水化和水泥微观结构.
研究的目的:
- 为了研究酸对水泥泥热量演变,微观结构,相位组成和混凝土压力强度的影响.
- 为了分析酸和一个可塑化添加剂的连续引入.
- 评估对混合粘合剂系统 (90%的波特兰水泥,10%的酸水泥) 的影响.
主要方法:
- 将5%的酸添加到粘合剂质量中.
- 在水化水泥泥泥过程中分析热量演变.
- 混凝土糊的微观结构和相位组合分析.
- 对细粒度混凝土进行压力强度测试.
主要成果:
- 酸增加了AFt和AFm阶段,延迟了三酸水化,最初加速然后延迟了贝莱特水化.
- 三亚酸和四亚酸的化加快,特别是在前24小时内.
- 在最初的24小时内,热量演变增加了4.3倍,诱导周期缩短了5倍.
- 早期的压力强度提高了6.4倍.
结论:
- 酸显著改变了混合水泥系统的水化动力学和阶段发展.
- 添加剂促进了加速的早期力量发展和增强的热演变.
- 这些发现表明,使用酸优化水泥材料性能有潜力.
相关概念视频
Plasticizers
65
Water-reducers, or plasticizers, are chemical admixtures used in concrete to improve strength and workability. These additives reduce the water-cement ratio without compromising workability, lower the cement content while maintaining the same workability, or increase workability to assist concrete placement in inaccessible areas.
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
65
Superplasticizers
77
Superplasticizers are advanced admixtures that enhance the workability of concrete by lowering the water content without compromising the strength of the material. These substances are highly effective water reducers, improving concrete flow, making it easier to work with, and enabling concrete to reach inaccessible areas or densely reinforced sections without mechanical vibration. The key components in superplasticizers are either sulfonated melamine or naphthalene formaldehyde condensates,...
77
Retarders
61
Retarders are chemical admixtures designed to extend the setting time, which is especially useful when there is a delay in sequential concrete pours to prevent cold joints and to achieve a cohesive structure. Retarders, when used in appropriate amounts, can also enhance the architectural appearance of exposed aggregate finishes.
The function of retarders is to delay the setting of concrete, and this effect can be measured using a penetration test. The retardation process involves adding...
The function of retarders is to delay the setting of concrete, and this effect can be measured using a penetration test. The retardation process involves adding...
61
Pore Size Distribution
86
In concrete, the pore size distribution significantly influences the material's properties. Capillary pores, markedly larger than gel pores, form a vast network within partially hydrated cement paste, reducing the concrete's strength and increasing its permeability. This heightened permeability leads to a greater risk of damage from environmental factors like freeze-thaw cycles and chemical attacks, with the extent of vulnerability also being tied to the water-to-cement ratio.
Adequate...
Adequate...
86
Polymer Classification: Stereospecificity
2.4K
Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
2.4K
Deleterious Substances in Aggregate
144
Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
Another type of impurity is clay and fine material that...
Another type of impurity is clay and fine material that...
144


