Development of Fly Ash/slag Cement Using Alkali-activated Reaction(2) - Reaction products and microstructure -

알칼리 활성반응을 이용한 플라이 애쉬/슬래그 시멘트 개발(2) - 반응생성물과 미세구조 -

  • Park, Sang-Sook (Division of Civil and Environmental Engineering, Sunchon National University) ;
  • Kang, Hwa-Young (Department of Civil and Environmental, Hanyeong College) ;
  • Han, Kwan-Su (Division of Civil and Environmental Engineering, Sunchon National University)
  • 박상숙 (순천대학교 토목.환경공학부) ;
  • 강화영 (한영대학 토목환경과) ;
  • 한관수 (순천대학교 토목.환경공학부)
  • Published : 2007.07.31

Abstract

Investigation of alkali activation of fly ash and blast furnace slag was carried out using waterglass and sodium hydroxide. XRD, FTIR, $^{29}Si$ and $^{27}Al$ NMR, TGA and SEM were used to observed the reaction products and microstructure of the fly ash/slag cement (FSC) pastes. The reaction products were amorphous or low-ordered calcium silicate hydrate and aluminosilicate gel produced from alkali activation of blast furnace slag and fly ash, respectively. On the basis of this investigation, waterglass solution with a modulus(Ms) of 1.0 and 1.2 is recommended for alkali activation of fly ash and blast furnace slag. Morphology of FSC pastes alkali-activated with Ms of 1.0 and 1.2 shows a more solid and continuous matrix due to restructuring of gel-like reaction products from alkali-activated fly ash and blast furnace slag together with another hydrolysis product(i.e., silica gel) from water glass.

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