Deyu Kong , Zhentao Han , Zhiyang Chen , Chenxu Ni , Haotian Wu , Yaqian Liang , Kui He , Jintao Liu
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引用次数: 0
Abstract
In the synthesis process of superabsorbent polymer (SAP), calcium sulfate dihydrate (C$H2) dispersion in water or colloidal silica sol (CSS) was used for the modification of SAP. The effects of modification on water absorption of SAP in water or saturated calcium hydroxide (CH) solution and the impacts and mechanism of the modified SAP on the performance of UHPC were investigated. The results showed that the modification results in a significant decrease in water absorption in both tap water and saturated CH solution for the SAP with water-based dispersion, but an increase in saturated CH solution though a decrease in tap water for that with the CSS-based dispersion. The SEM observation showed that a large amount of long ettringite crystals formed around the voids left by the SAP modified with the water-based dispersion. However, few ettringite crystals but more hydration products were observed to fill in the voids and a C-S-H gel shell-structure was also found in the voids left by the SAP modified with the CSS-based dispersion. Because of these, it was interestingly found that the crack resistance was further improved and a significant improvement in both flexural and compressive strength was observed, though the internal curing effect was weakened because some internal curing water carried by the SAP was consumed during the formation of the ettringite crystals and the C-S-H gels in the voids.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.