Development of Reaction Acceleration Technology for Blast Furnace Slag and Fly Ash Cement Concrete

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04349
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 23010:Building structures and materials-related
• Research Institution: Hokkaido University
• Principal Investigator: Kurumisawa Kiyofumi 北海道大学, 工学研究院, 准教授 (40374574)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 反応促進 / 高炉スラグ微粉末 / フライアッシュ / CO2排出 / 無機塩 / 硫酸ナトリウム

Outline of Final Research Achievements

The objective of this study was to develop a reaction accelerator that enables the use of large quantities of supplemental materials to replace cement in order to reduce CO2 emissions. As a result, the initial reaction of blast furnace slag and fly ash with calcium hydroxide as an activator was accelerated by the addition of sodium sulfate. It was also clarified that the addition of sodium sulfate promoted the reaction and strength development of the hardened cement paste when it was mixed with cement. On the other hand, the addition of sodium sulfate promoted the initial reaction and strength development, but the strength development after 28 days of age was not so high. This may be due to the formation of a large amount of reaction products in the early stage. It was found that the acceleration of the initial reaction was dependent on ion mobility and solubility.

Free Research Field

建築材料

Academic Significance and Societal Importance of the Research Achievements

建設業界におけるCO2排出削減のためにセメントの利用を低減させるために高炉スラグやフライアッシュによるセメントの置換がさらに必要であり、それを実現するためには初期の強度発現を改善することが必要であり、本研究では反応促進剤として硫酸ナトリウムの添加が有効であること明らかにした。また、その促進メカニズムはイオン移動度が高い陰イオンが有効であり、さらに無機塩の溶解度が重要であることを明らかにした。今後この知見を活かしてさらに有効な促進剤の開発が望まれる。