SEM與SSNMR應用於鹼活化混合爐碴膠結材料微觀結構分析

INVESTIGATION ON THE MICROSTRUCTURE OF ALKALI-ACTIVATED MIXED SLAG BY SEM AND SSNMR

鐘文煥(Wen-Huan Zhong) ； 黃偉慶(Wei-Hsing Huang)

《中國土木水利工程學刊》 29卷1期 (2017/03) Pp. 37-46

https://doi.org/10.6652/JoCICHE/2016-02901-05

摘要

鹼活化混合爐碴為爐石粉與還原碴混合後經由鹼活化劑活化所形成的膠結材，具有良好的強度發展與較佳的抗化學侵蝕能力，是一種具有發展潛力的綠建材。本研究依一定比例混合爐石粉與還原碴，並以兩種不同濃度的鹼活化劑製成鹼活化混合爐碴，藉由掃描式電子顯微鏡 (scanning electron microscopy, SEM) 以及固態核磁共振光譜儀 (solid-statenuclear magnetic resonance spectroscopy, SSNMR) 進行微觀分析。實驗結果顯示，鹼活化混合爐碴多為非結晶型化合物，隨著齡期與鹼活化劑濃度增加而更加緻密。漿體內的鋁原子大多與矽化合物共同架構成低鈣矽比的C-A-S-H 膠體，因鋁原子位於膠體穩定架構內部，故針對鋁化合物不利的化學侵蝕作用無法造成顯著的影響，說明了鹼活化漿體抗化學侵蝕較佳的部分原因

關鍵字

鹼活化混合爐碴 ； 掃描式電子顯微鏡 ； 固態核磁共振光譜儀

並列摘要

Alkali-activated mixed slag is a binder made by mixing blast furnace slag and ladle slag and activated using alkali activator. The binder exhibits good strength development and better resistance to chemical attack than ordinary Portland cement, thus shows potential in making green concrete. In this study, the mixed slag was produced by blast furnace slag and ladle slag mix at a specific weight percent and then activated by an alkali activator prepared by liquid sodium silicate and sodium hydroxide. The microstructure of alkali-activated mixed slag paste was observed by scanning electron microscopy (SEM) and solid-state nuclear magnetic resonance spectroscopy (SSNMR). The results show that hydration products of alkali-activated mixed slag are amorphous and become more dense in structure with time and concentration of activator. Aluminum ion combines silicon ion or compound and produces C-A-S- H gel with low Ca/Si ratio. The aluminum ion is in the inner portion of the gel, hence chemical attacks against aluminum ions and compounds become difficult to effect. This in turn explains why alkali-activated binder shows improved resistance to chemical attacks.

並列關鍵字

alkali-activated mixed slag ； scanning electron microscopy (SEM) ； solid-state nuclear magnetic resonance spectroscopy (SSNMR)