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Fundamental Properties of Mortar and Concrete Using High Calcium Fly Ash

고칼슘 플라이애시를 활용한 모르타르 및 콘크리트의 기초적 물성

  • Lee, Min-Hi (Department of Architecture, Howon University)
  • Received : 2016.08.30
  • Accepted : 2016.09.21
  • Published : 2016.09.30

Abstract

To evaluate the properties of inorganic composites using a great quantity of high-calcium fly ash generated in combined heat and power plants, high-calcium fly ash and F-class fly ash commonly used as concrete admixtures were substituted with binding materials to examine changes of fluidity and compressive strength depending on the substitution ratio for each curing temperature. According to the experimental result, CFA-mixed mortar showed a tendency to reduce its flow unlike FFA-mixed mortar as the substitution ratio was increased, but its flow loss showed smaller than FFA as time passed. As a result of examining compressive strength depending on mixing FA, FFA-mixed mortar had an optimum range within 50% when curing at ambient temperature, but it was found that the compressive strength is reduced when mixing CFA. When curing at high temperature, FFA did not relatively have a great effect on the substitution ratio, but CFA could expect a strength enhancement effect compared with 100% of OPC when using within 25% of binding materials.

순환유동층 연소방식에서 발생하는 석탄재인 고칼슘 플라이애시를 활용한 무기결합재의 모르타르 및 콘크리트 물성 평가하였다. 그 결과 고온양생조건에서 CFA 혼입 모르타르의 재령 28일 압축강도는 혼입율 25% 범위에서 압축강도는 다소 증가하지만, 그 이상의 범위에서는 혼입율이 증가할수록 압축강도는 저하하는 경향을 보여, 고온양생 사용시 25%이내의 혼입율이 적정할 것으로 사료된다. 또한 고온양생의 경우 CFA 및 BFS 활용한 결합재를 사용한 콘크리트의 압축강도는 OPC를 사용한 콘크리트와 비교하여 재령 1일의 초기 강도 및 재령 28일 이후의 장기강도가 높게 발현되고 있으며, CFA 및 BFS 활용한 결합재 사용에 따른 압축강도 증진은 보다 효과적인 것으로 판단된다.

Keywords

References

  1. An, Y.J., Moon, K.J., Yoon, S.J., Lee, M.H., Song, Y.C., Kim,Y.R. (2013). Physical properties of finishing mortar in ondolfloor using high-calcium fly ash, Journal of Korea Society of Waste Management, 30(7), 660-669 [in Korean]. https://doi.org/10.9786/kswm.2013.30.7.660
  2. Ahn, N.S., Lee, J.H., Lee, Y.H. (2011). Sulfate attack according to the quantity of composition of cement and mineral admixtures, Journal of Korea Institute Building Construction, 11(6), [in Korean].
  3. ASTM C 1581-048. (2009). Standard test method for determining age at cracking and induced tensile stress characteristics of mortar and concrete under restrained shrinkage, American Society of Testing and Material.
  4. Horiguchi, I. (2008). Compressive strength of PFBC coal ash composite with resistance to sulfuric acid solution, JCI' 2008, 30(2), 529-534.
  5. Kim, K.H., Lim, J.Y., Ryu, D.H., Choi, S.W. (2007). The present situation of production and it's utilization of electronic arc furnace oxidizing slag in korea and other countries, Magazine of the Korea Concrete Institute, 19(6), 51-57 [in Korean]. https://doi.org/10.22636/MKCI.2007.19.6.51
  6. Lee, U. (2012). A Study on the Fluidization of Bed Materials for a CFB Boiler, Master's Thesis, Pusan National University [in Korean].
  7. Sasaki, H. (1997). "Studies on the effective utilization of coal ash generated from pressurized fluidized-bed combustion power plant", Proceeding of Japan Concrete Institute, 19(1), 229-234.
  8. Sim, J.S., Lee, K.G., Kim, Y.T., Kang, S.K. (2012). Hydration characteristics of coal-fly ash containing high CaO compound, Journal of the Korean Ceramic Society, 49(2) [in Korean].