DOI QR코드

DOI QR Code

Characteristics of Natural Loess (Hwangtoh) Paste Subjected to Geopolymerization

Geopolymerization을 적용한 천연황토 페이스트의 특성

  • Kim, Baek-Joong (School of Civil, Environmental and Architectural Engineering) ;
  • Choi, Hee-Bok (Doosan Engineering & Construction Technology Research Institute) ;
  • Kang, Kyung-In (School of Civil, Environmental and Architectural Engineering) ;
  • Yi, Chong-Ku (School of Civil, Environmental and Architectural Engineering)
  • 김백중 (고려대학교 건축사회환경공학부) ;
  • 최희복 (두산건설(주) 기술연구소) ;
  • 강경인 (고려대학교 건축사회환경공학부) ;
  • 이종구 (고려대학교 건축사회환경공학부)
  • Received : 2010.09.30
  • Accepted : 2010.12.10
  • Published : 2011.02.28

Abstract

In this study, possible use of indigenous natural loess (Hwangtoh) as a new binding material via geopolymerization process is examined. Hwangtoh pastes with four different mix proportions of varying alkali liquid concentrations (6 M, 8 M) and the constituents of the binder as well as the alkali liquid at a constant liquid-to-binder ratio of 0.55 were prepared. Analysis of the natural loess (Hwangtoh) paste was carried out as follows : 1) Measurement of compressive strength and weight of cubic specimens versus curing time; 2) Analysis by X-ray diffraction (XRD) and scanning electron microscope (SEM) about reaction product; 3) Porosity analysis of hardened Hwangtoh paste. The result showed that it is possible to prepare Hwangtoh paste with 29.1 MPa at the age of 7 day by using alkali solution (made as 1 : 4.5 the mass ratio of liquefied $Na_2SiO_3$ and NaOH solution and applying the curing temperature of $60^{\circ}C$). Compressive strength development with respect to the degree of moisture evaporation from the paste seems to be independent of curing temperature. Therefore, it seems that higher early strength of the paste specimens cured at higher temperature can be attributed to both higher rate of reaction and moisture evaporation.

이 연구는 친환경적인 콘크리트 결합재로서 천연황토의 적용 가능성을 알아보기 위해 지오폴리머 반응법(geopolymerization)으로 얻어진 천연황토 경화체의 특성을 분석하였다. 이를 위해 천연황토와 알칼리 용액을 1 : 0.55 비율로 혼합하여 천연황토 페이스트를 제조하고 $60^{\circ}C$$20^{\circ}C$에서 양생시켜 재령에 따른 압축강도와 중량변화를 측정하였다. 또한, X-ray 회절분석(XRD)을 통해 반응 생성물을 확인하고 그 형상을 주사전자현미경(SEM)으로 촬영하였으며 수은압입법으로 경화체의 공극률을 분석하였다. 그 결과, 지오폴리머 반응법으로 얻어진 천연황토 경화체는 액상 규산나트륨($Na_2SiO_3$)와 8 M 수산화나트륨(NaOH) 수용액을 1:4.5비율로 제조한 알칼리 용액을 사용하고 $60^{\circ}C$에서 7일간 양생하였을 때 압축강도 29.1 MPa을 발현하는 천연황토 페이스트의 제조가 가능하였다. 또한, 개별 양생온도($20^{\circ}C$, $60^{\circ}C$)에서 압축강도 발현은 수분증발 비율에 따라 유사한 경향을 나타내므로 수분증발에 유리한 높은 양생 온도에서 반응을 유도하는 것이 조기 강도 발현에 유리한 것으로 사료된다.

Keywords

References

  1. Feret, R., “Slags for the Manufacture of Cement,” Rev. Mater. Constr. Trav., 1939, 145 pp.
  2. Purdon, A. O., “The Action of Alkalis on Blast Furnace Slag,” J. Soc. Chem. Ind., Vol. 24, 1940, pp. 191-202.
  3. Glukhovsky, V. D., “Soil Silicates,” Kiev. USSR, Gostroiizdat Publish, 1959.
  4. Davidovits, J., “Synthesis of New High Temperature Geo-Polymers for Reinforced Plastics/Composites,” SPE PACTEC 79 Society of Plastic Enginners, Brrokfield Center, 1979, pp. 151-154.
  5. Fernando Pacheco-Torgala, Joao Castro-Gomesb, and Said Jalalic, “Alkali-Activated Binders: A Review: Part 1. Historical Background, Terminology, Reaction Mechanisms and Hydration Products,” Construction and Building Materials, Vol. 22, 2008, pp. 1305-1314. https://doi.org/10.1016/j.conbuildmat.2007.10.015
  6. Fernando Pacheco-Torgala, Joao Castro-Gomesb, and Said Jalalic, “Alkali-Activated Binders: A Review. Part 2. About Materials and Binders Manufacture,” Construction and Building Materials, Vol. 22, 2008, pp. 1315-1322. https://doi.org/10.1016/j.conbuildmat.2007.03.019
  7. Majumdar, A. J., Singh, B., and Edmonds, R. N., “Hydration of Mixtures of C12A7 and Granulated Blastfurnace Slag,” Cement and Concrete Research, Vol. 19, 1989, pp. 848-856. https://doi.org/10.1016/0008-8846(89)90097-5
  8. Wu, X., Jiang, W., and Roy, D. M., “Early Activation and Properties of Slag Cement,” Cement and Concrete Research, Vol. 20, 1990, pp. 961-974. https://doi.org/10.1016/0008-8846(90)90060-B
  9. Wang, S. D. and Scrivener, K. L., “Hydration Products Microstucture of Alkali Activated Slag Cement,” Cement and Concrete Research, Vol. 25, 1995, pp. 561-571. https://doi.org/10.1016/0008-8846(95)00045-E
  10. Fernandez-Jimenez, A. and Puertas, F., “Alkali-Activated Slag Cements: Kinetic Studies,” Cement and Concrete Research, Vol. 27, 1997, pp. 359-368. https://doi.org/10.1016/S0008-8846(97)00040-9
  11. Fernandez-Jimenez, A., Palomob, J. G., and Puertas, F., “Alkali-Activated Slag Mortars : Mechanical Strength Behaviour,” Cement and Concrete Research, Vol. 29, 1999, pp. 1313-1321.
  12. Katz, A., “Microscopic Study of Alkali-Activated Fly Ash,” Cement and Concrete Research, Vol. 28, 1998, pp. 197-208. https://doi.org/10.1016/S0008-8846(97)00271-8
  13. Palomo, A., Grutzeck, M. W., and Blanco, M. T., “Alkali-Activated Fly Ashes. a Cement for the Future,” Cement and Concrete Research, Vol. 29, 1999, pp. 1323-1329. https://doi.org/10.1016/S0008-8846(98)00243-9
  14. Criado, M., Palomo, A., and Fernandez-Jimenez, A., “Alkali Activation of Fly Ashes. Part 1 : Effect of Curing Conditions on the Carbonation of the Reaction Products,” Fuel, Vol. 84, 2005, pp. 2048-2054. https://doi.org/10.1016/j.fuel.2005.03.030
  15. Palomo, A., Blanco-Varela, M. T., Granizo, M. L., Puertas, F., Vazquez, T., and Grutzeck, M. W., “Chemical Stability of Cementitious Materials Based on Metakaolin,” Cement and Concrete Research, Vol. 29, 1999, pp. 997-1004. https://doi.org/10.1016/S0008-8846(99)00074-5
  16. Alonso, S. and Palomo, A., “Calorimetric Study of Alkaline Activation of Calcium Hydroxide–Metakaolin Solid Mixtures,” Cement and Concrete Research, Vol. 31, 2001, pp. 25-30. https://doi.org/10.1016/S0008-8846(00)00435-X
  17. Alonso, S. and Palomo, A., “Alkaline Activation of Temperature, Activator Concentration and Solids Ratio,” Materials Letters, Vol. 47, 2001, pp. 55-62. https://doi.org/10.1016/S0167-577X(00)00212-3
  18. 황혜주, 노태학, 양준혁, “황토결합재를 이용한 콘크리트의 적정배합 도출에 관한 연구,” 대한건축학회논문집 구조계, 23권, 2호, 2007, pp. 73-80.
  19. 황혜주, 강남이, “친환경 무시멘트 황토결합재의 적용가능성에 관한 연구,” 한국생태환경건축학회논문집, 8권, 2008, pp. 81-84.
  20. 최성우, 최희용, 황혜주, 김문한, 김무한, “혼화재로서 황토를 사용한 콘크리트의 기초 물성에 관한 실험적 연구,” 대한건축학회 학술발표논문집, 20권, 2호, 2000, pp. 419-422.
  21. 이현철, 고성석, “활성황토를 혼입한 모르터의 물리적 특성에 관한 연구,” 대한건축학회논문집 구조계, 23권, 3호, 2007, pp. 77-88.
  22. 최희용, 황혜주, 김무한, 김문한, “시멘트 모르터로의 적용을 위한 황토 혼화재 개발에 관한 연구,” 대한건축학회 논문집 구조계, 16권, 6호, 2000, pp. 95-102.
  23. 양근혁, 황혜주, 김성영, 송진규, “황토결합재를 사용한 무시멘트 모르터의 배합특성에 따른 압축강도 및 건조 수축 거동,” 대한건축학회논문집 구조계, 22권, 6호, 2006, pp. 87-94.
  24. Yang, K. H., Hwang, H. Z., Kim, S. Y., and Song, J. K., “Development of a Cementless Mortar Using Hwangtoh Binder,” Building and Environment, Vol. 42, 2007, pp. 3717-3725. https://doi.org/10.1016/j.buildenv.2006.09.006
  25. Kumar Metha, P. and Paulo J. M. Monteiro, “Concrete : Microstucture, Properties, and Material,” McGraw- Hill, New York, 2006, pp. 32-33.

Cited by

  1. Manufacture of Yellow Ocher Polystyrene-Based Hybrid Nanoparticles for High-Performance PET Applications vol.38, pp.8, 2014, https://doi.org/10.3795/KSME-B.2014.38.8.701
  2. Feasibility Study of Loess Stabilization with Fly Ash–Based Geopolymer vol.28, pp.5, 2016, https://doi.org/10.1061/(ASCE)MT.1943-5533.0001490