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Reaction Characteristics of Geopolymer Paste Incorporating Fly-ash and GGBS

플라이애쉬와 고로슬래그 미분말을 혼입한 지오폴리머 페이스트의 반응특성 분석

  • Shin, Ki-Su (Department of Architectural Engineering, Kangwon University) ;
  • Park, Ki-Bong (Department of Architectural Engineering, Kangwon University)
  • Received : 2020.06.29
  • Accepted : 2020.07.15
  • Published : 2020.08.20

Abstract

The addition of a limestone filler(LF) to fill into the voids between cement and aggregate particles can reduce the cementitious paste volume. In previous studies, it has been found that the addition of LF to reduce the cementitious paste volume would substantially increase the compressive strength, and reduce the heat generation. This paper aim to evaluate the influence of LF contents on the hydration kinetics and compressive strength. Hydration kinetics were evaluate using heat of hydration, ignition loss and thermal analysis. The heat of hydration was measured using Isothermal Calorimetry. The degree of hydration was measured using ignition loss. Hydration product analysis was carried out by Thermal Gravimetric and Differential Thermal Analysis. The results show that the addition of LF reduces not only the initial setting time and heat of hydration peak, also degree of hydration and rate of strength development at early age increase with the addition of LF. It can be concluded the LF fills the pore between cement particles due to formation of carboaluminate, which may accelerate the setting of cement pastes.

지오폴리머의 반응성은 원재료의 구성성분 및 Si/Al비, Na/Al비, 물-결합재비, 비정질 요소 등을 고려하여 명확한 메커니즘을 규명하는 것은 매우 중요하다. 따라서 원재료 및 알칼리 활성화제의 구성성분을 고려한 %Na2O, Ms는 반응성을 결정하는 중요한 요소가 된다. 하지만 다수의 연구에서는 알칼리 활성화제의 농도와 양생 조건 등의 기본적인 요소만을 고려하는 한계점을 나타내고 있다. 따라서 본 연구에서는 %Na2O, Ms 및 고로슬래그 미분말의 혼입량에 따른 지오폴리머 페이스트의 강도특성, 반응열, 길이변화, 미세구조 분석을 실시하였다.

Keywords

References

  1. Tennakoon, C.K. Assessment of properties of ambient cured geopolymer concrete for construction applications [doctor's thesis]. [Melbourne (Australia)]: Swinburne University, 2016. 256 p.
  2. Swamy RN. Cement replacement materials. United Kingdom: Blackie Academic & Professional; 1986. 259 p.
  3. Pacheco-Torgal F, Castro-Gomes J, Jalali S. Alkali-activated binders: A review: Part 1. Historical background, terminology, reaction mechanisms and hydration products. Construction and Building Materials. 2008 Jul;22(7):1308-14. https://doi.org/10.1016/j.conbuildmat.2007.10.015
  4. Marjanovic N, Komljenovic M, Bascarevic Z, Nikolic, V, Petrovic R. Physical-mechanical and microstructural properties of alkali-activated fly ash-blast furnace slag blends. Ceramic International. 2015 Jan;41(1):1421-35. https://doi.org/10.1016/j.ceramint.2014.09.075
  5. Hardjito D, Wallahm SE, Sumajouwm DM, Ranganm BV. On the development of fly ash based geopolymer concrete. ACI Materials Journal. 2004 Dec;101(6):467-72.
  6. Karakoc MB, Turkmen I, Maras M, Kantarci F, Demirboga R, Toprak MU. Mechanical properties and setting time of ferrochrome slag based geopolymer paste and mortar. Construction and Building Materials. 2014 Dec;72:283-92. https://doi.org/10.1016/j.conbuildmat.2014.09.021
  7. Silva PD. Sagoe-Crenstil K, Sirivivatnanon V. Kinetics of geopolymerization: role of Al2O3 and SiO2. Cement and Concrete Research. 2007 Apr;37(4):512-8. https://doi.org/10.1016/j.cemconres.2007.01.003
  8. Siyal AA, Azizli KA, Man Z, Ullah H. Effects of parameters on the setting time of fly ash based geopolymers using taguchi method. Procedia Engineering. 2016;148:302-7. https://doi.org/10.1016/j.proeng.2016.06.624
  9. Jaarsveld JGSV, Deventer JSJV, Lorenzen L. The potential use of geopolymeric materials to immobilise toxic metals: Part I. Theory and applications. Minerals Engineering. 1997 Jul;10(7):659-69. https://doi.org/10.1016/S0892-6875(97)00046-0
  10. Lee WKW, Van Deventer JSJ. Chemical interactions between siliceous aggregates and low-Ca alkali-activated cements. Cement and Concrete Research. 2007 Jun;37(6):844-55. https://doi.org/10.1016/j.cemconres.2007.03.012
  11. Palomo A, Grutzeck MW, Blanco MT. Alkali-activated fly ashes: A cementfor the future. Cement Concrete Research. 1999 Aug;29(8):1323-9. https://doi.org/10.1016/S0008-8846(98)00243-9
  12. Lee BK, Kim GG, Kim RH, Cho BS, Lee SJ, Chon CM. Strength development properties of geopolymer paste and mortar with respect to amorphous Si/Al ratio of fly ash. Construction and Building Materials. 2017 Oct;151:512-9. https://doi.org/10.1016/j.conbuildmat.2017.06.078
  13. Yunsheng Z, Wei S, Zongjin L, Xiangming Z, Eddie Chungkong C. Impact properties of geopolymer based extrudates incorporated with fly ash and PVA short fiber. Construction and Building Materials. 2008 Mar;22(3):370-83. https://doi.org/10.1016/j.conbuildmat.2006.08.006
  14. Zheng YC. Shrinkage of Geopolymer [master;s thesis]. [Melbourne (Australia)]: The university of Melbourne; 2009. 110 p.
  15. Collins F, Sanjayan JG. Effect of pore size distribution on drying shrinkage of alkali-activated slag concrete. Cement and Concrete Research. 2000 Sep;30(9):1401-6. https://doi.org/10.1016/S0008-8846(00)00327-6
  16. Duxson P, Mallicoat SW, Lukey GC, Kriven WM, van Deventer JSJ. The effect of alkali and Si/Al ratio on the development of mechanical properties of metakaolin-based geopolymers. Colloids Surface A: Physicochemical and Engineering Aspects. 2007 Jan;292(1):8-20. https://doi.org/10.1016/j.colsurfa.2006.05.044