DOI QR코드

DOI QR Code

The Plastic Cracking Properties of Fly Ash Concrete with Various Curing Conditions

양생조건에 따른 플라이애쉬 콘크리트의 소성수축균열 특성

  • Published : 2007.03.20

Abstract

In this study, the property and plastic cracking pattern of concrete were compared and analyzed with the replacement ratio of fly ash 0, 5, 10, 15, 20% by cement weight. And curing conditions of concrete were given variously such as indoors(with wind speed as 0, 300, 500m/min), outdoors and chamber. The hydration temperature had a tendency to decrease as the replacement ratio of fly ash increased, and in the case of the wind speed 0m/min, it was showed that the moment that the amount of evaporation of water from surface of reference concrete was more than the volume of bleeding was 90 min since casting concrete. The time that the crack initiated had a tendency to be more quickly as the replacement ratio of fly ash increased. The number, length, width and area of crack in the indoor curing, exposed outdoor curing, enclosed outdoor curing had a tendency to decrease as the replacement ratio of fly ash increased. The crack had a tendency to decrease in sequence of exposed outdoor, enclosed outdoor curing, indoors curing. The outbreak of cracking by the change of temperature and humidity was affected by relative humidity more than temperature and the cracking had a tendency to increase as relative humidity lowered.

Keywords

References

  1. 문승호, "콘크리트 구조균열", 기문당, 2001
  2. 한국콘크리학회, "최신콘크리트공학" 2005, pp. 505-525
  3. 김진근, "콘크리트 균열의 원인", 한국콘크리트학회, Vol.6 No.4, 1994, pp. 6-16
  4. 최완철, "콘크리트 구조물의 균열체계에 따른 균열제어와 대책", Vol.6 No.4, 1994, pp. 17-24
  5. 한국과학기술원, "콘크리트 구조물의 균열 제어 기술 개발", 과학기술부, 2000, pp 203-213
  6. Kraai, paul P., "A proposed Test to Determine the Cracking Potential Dueto Drying Shrinkage of Concrete." Concrete Construction, V.30, No.9, Sept. 1985, pp. 775-778
  7. Concrete Society Report, "Non-structural Cracks in Concrete", Technical Report No.22, 3rd Edn, pp. 44
  8. Shalon, R., and Ravina, D., "Studies in Concreting in Hot Countries,", Proceedings, International Symposium on Concrete and Reinforced Concrete in Hot Countries, Building Research Institute, Haifa, 1960, V.1, pp. 46
  9. Lerch, W., "Plastic Shrinkage," ACI Journal, Proceedings V.53, NO.8, Feb. 1957, pp. 797-802
  10. BAMFORTH, P.B. "Insitu measurement of the effects of partial Portland cement replacement using either flyash or ground granulated blast furnace slag on the performance of mass concrete." Proceeding of the Instiution of Civil Engineers. Part 2. Vol.69. Sept. 1980. pp. 777-800 https://doi.org/10.1680/iicep.1980.2377
  11. Davis, "Properties of Cements and Concretes Containing Fly Ash", ACI J. Proc., Vol. 33. No. 5, May-June. 1937, pp. 577-612
  12. KRAL, S. and GEBAUER, J. "Shrinkage and cracking of concrete at early ages. Proceedings of International Symposium on Slabs.' Dundee 1979. Advances in Concrete Slab Technology. London, Pergamon Press, 1980. pp. 412-420