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Resistance to Sea Water of Hardened Cement with Calcium Sulfoaluminate Type Expansive Additives(I)

칼슘 설포알루미네이트계 팽창재를 혼합한 시멘트 경화체의 내해수성(I)

  • 전준영 (단국대학교 신소재공학과) ;
  • 송종택 (현대시멘트 연구개발과)
  • Published : 2003.03.01

Abstract

Hardened cement pastes of OPC which contains 10 wt% CSA type expansive additives were immersed in aqueous solution of 10 wt% MgS $O_4$.7$H_2O$ and then investigated by compressive strength, XRD. SEM and DSC etc.. According to the results including the hydration products and the microstructure of the hardened paste, the case of CSA type expansive additives[No. 6(C/(equation omitted) : 2.29, A/(equation omitted) : 0.16)] prepared from raw materials increased the resistance to $Mg^{2+}$, S $O_4$$^{2-}$ ion diffusion than that of OPC paste due to the densification by the formation of fine ettringite in the first stage and the hydrates according to $\beta$-C$_2$S hydration in the late period.

보통 포틀랜드 시멘트에 CSA계 팽창재를 l0 wt% 혼합한 시멘트 경화체를 MgS $O_4$. 7$H_2O$ l0 wt%로 제조된 용액에 침지시켜 물성을 측정하였다. 재령의 경과에 따라서 압축강도, 수화생성물 및 미세구조변화를 관찰한 결과 천연원료로 제조된 CSA계 팽창재[No. 6(C/(equation omitted) : 2.29, A/(equation omitted) : 0.16)]는 초기에 미세한 에트링자이트 생성 및 후기에는 $\beta$-C$_2$S의 수화 반응으로 경화체가 치밀화되어 OPC 보다 $Mg^{2+}$, S $O_4$$^{2-}$ 이온의 확산에 대한 저항성이 증가되었다.

Keywords

References

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