Choonghyun Kang, Taewan Kim, Yong-Myung Park, Ki-Young Seo
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引用次数: 0
Abstract
Recently, research results on PC-based or alkali-activated slag cement (AASC) using seawater as mixing water have been reported. Unlike seawater, reverse osmosis brine (brine) is waste discharged into the ocean from seawater desalination plants. There is a need to develop new and effective methods of disposing or utilizing brine to reduce marine pollution, protect marine ecosystems, and increase marine plant construction. However, research on cement or concrete using brine as a mixing water is very limited. Brine has almost the same composition as seawater, and the ion concentration is 2–4 times higher. Therefore, it is believed that new methods of using brine can be investigated and developed based on existing research and experimental results on seawater. The effects of brine and aluminum oxide (AO) on activated slag with calcium hydroxide (CH) were investigated for hydration and mechanical properties. 5% and 10% of CH were used, and samples using fresh water (FC) were prepared at the same time for comparison with brine. The slag sample without CH has a low initial (1 and 3d) strength of about 10 MPa for both FC and brine, but increases rapidly from 7d. Incorporation of CH was effective in improving the mechanical performance of FC and brine samples. In addition, the brine sample exhibited higher strength than the FC sample because it formed fewer C3AH6 phases that cause volume instability than the FC sample and affected the hydration promotion of slag particles. And more calcite phases were observed in the brine samples than in the FC samples. Through this study, the possibility of using brine as a building material was confirmed. In addition, the effect of chloride ion adsorption of slag mixed with AO and CH on the physical properties and mechanical performance of the hydration reaction was confirmed.
期刊介绍:
The International Journal of Concrete Structures and Materials (IJCSM) provides a forum targeted for engineers and scientists around the globe to present and discuss various topics related to concrete, concrete structures and other applied materials incorporating cement cementitious binder, and polymer or fiber in conjunction with concrete. These forums give participants an opportunity to contribute their knowledge for the advancement of society. Topics include, but are not limited to, research results on
Properties and performance of concrete and concrete structures
Advanced and improved experimental techniques
Latest modelling methods
Possible improvement and enhancement of concrete properties
Structural and microstructural characterization
Concrete applications
Fiber reinforced concrete technology
Concrete waste management.