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Effect of Phosphate Types on the Strength and pH of Magnesia-Phosphate Composites

마그네시아 인산염 복합체의 강도 및 pH에 대한 인산염 종류의 영향

  • Lee, Kyung-Ho (Department of Architectural Engineering, Graduate School, Kyonggi University) ;
  • Yang, Keun-Hyeok (Department of Plant.Architectural Engineering, Kyonggi University)
  • Received : 2016.09.06
  • Accepted : 2017.02.10
  • Published : 2017.04.20

Abstract

As an elementary investigation to develop vegetation concrete with a relatively low pH value, magnesia-phosphate composites (MPC) were examined according to the phosphate types including Monoammonium, Monosodium, Monopotassium, Monocalcium, Diammonium, Disodium, Dipotassium, and Diacalcium phosphates. All of the MPC binders, the ratio of magnesia to phosphate was fixed to be 7:3. MPC mortars activated with Disodium, Dipotassium, and Diacalcium phosphates showed no compressive strength gain, even at age of 28 days. Meanwhile, MPC mortars with Monoammonium and Monosodium phosphates developed 28-day compressive strength of more than 34MPa, and showed a relatively low pH value below 9.8. Hence, Monoammonium and Monosodium phosphates have potentials as an activator for producing MPC-based vegetation concrete.

본 연구는 식생 콘크리트 개발에 대한 기초적인 연구로 낮은 pH특성을 갖는 마그네시아-인산염 복합체(MPC)의 압축강도 및 pH 특성을 평가하였다. 주요 변수는 인산염 종류이며, 8종의 인산염(암모늄계, 나트륨계, 칼륨계, 칼슘계)을 사용하여 모르타르 및 페이스트를 제작하였다. 실험결과, 제 2 인산나트륨, 제 2 인산칼륨 및 제 2 인산칼슘의 경우 MPC 모르타르의 압축강도 발현에 대한 영향은 없었다. 제 1 인산암모늄, 제 1 인산칼륨을 적용한 MPC모르타르의 경우 34MPa 이상의 압축강도가 발현되었으며, pH는 9.8이었다. 따라서 식생용 콘크리트의 결합재로 제 1 인산암모늄 및 제 1 인산칼륨인산염이 적용된 MPC가 가장 효과적일 것으로 기대된다.

Keywords

References

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