Journal of Urban Science (도시과학)

Urban Science Institute (인천대학교 도시과학연구원)
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Microstructural Characteristics of Alkali-Activated Cements Incorporating Fly Ash and Slag

플라이애시와 슬래그 혼합 알칼리 활성 시멘트의 미세구조 특성

  • 장정국 (인천대학교 도시과학대학 도시건축학부)
  • Received : 2018.06.19
  • Accepted : 2018.06.30
  • Published : 2018.06.30
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Abstract

This study investigates microstructural characteristics of alkali-activated cements incorporating slag and fly ash. Samples were prepared with four fly ash:slag ratios, i.e., 100:0, 90:10, 70:30 and 50:50, and they were synthesized by using an alkali activator. Microstructural characteristics of the alkali-activated cements were determined by XRD, TGA, SEM, N2 gas adsorption/desorption methods, and compressive strength test. The results showed that properties of alkali-activated fly ash/slag were significantly affected by slag contents. Alkali-activated fly ash/slag with slag content of 30-50% showed higher compressive strength than ordinary Portland cement paste. An increase in slag content resulted in a denser microstructure, which composed of amorphous gel, therefore contributed to strength development of the material.

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References

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