Effects of H$_2$BO$_3$ on the Hydration of $C_4$A$_3$S Blended Rapid Hardign Cement

CSA계 혼합 시멘트 수화에 미치는 Boric Acid 의 영향

  • Yoo, K.S. (Dept. of Inorg. Mater., Myong Ji Univ) ;
  • Lee, K.H. (Dept. of Inorg. Mater., Myong Ji Univ) ;
  • Kim, N.H. (Tong Yang Central Laboratories) ;
  • Lee, Y.S. (Tong Yang Central Laboratories) ;
  • Hun, K.H. (Dept. of Inorg. Mater., Myong Ji Univ) ;
  • Lee, J.W. (Dept. of Inorg. Mater., Myong Ji Univ) ;
  • Yim, Going (Fac. of Adv. Mat'ls Eng., Col. Of Eng, Paichai University)
  • 유광석 (명지공과대학 무기재료공학과) ;
  • 이경희 (명지공과대학 무기재료공학과) ;
  • 김남호 (동양중앙연구소) ;
  • 이양수 (동양중앙연구소) ;
  • 안광훈 (명지공과대학 무기재료공학과) ;
  • 이재원 (명지공과대학 무기재료공학과) ;
  • 임굉 (배재대학교 공과대학 신소재공학부)
  • Published : 1998.06.01

Abstract

The study was carried on the influence of {{{{ { {H }_{3 }BO }_{3 } }} for hydration of blended rapid hardening cement which was composed of {{{{ {{C }`_{4 } ^{ }A }_{3 } }} Adding {{{{ { {H }_{3 }BO }_{3 } }} to the mortar of blended rapid hardening cement delayed the setting time and increased the flow of the mortar. When {{{{ { {H }_{3 }BO }_{3 } }} added to the blended rapid hardening cement mono-sulfate was produced rather than ettringite and the existing time of monosulfate also prolonged. After hours monosulfate was converted to ettringite through being producted like gels. This monosulfate phase in-fluences on the setting time and flow of fresh mortar.

C1A3계 속경성 혼합시멘트에 대한 H3BO3의 첨가에 따른 mortar의 물성과 수화 생성물에 관한 연구를 하였다. H3BO3의 첨가는 응결 시간의 지연과 흐름성의 개선을 가져 왔다. H3BO3의 첨가에 따라 초기 수화 생성물은 monosulfate가 생성 되며 이 생성물이 존재하는 기간도 길어진다. 일단 monosulfate가 생성되면 그후 ettringite로 변화되면서 중간 단계로 gel상의 물질로 변화된다. 초기에 생성되어지는 monosulfate는 mortar의 응결시간과 flow에 영향을 준다.

Keywords

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