한국건설순환자원학회논문집 (Journal of the Korean Recycled Construction Resources Institute)

한국건설순환자원학회 (Korean Recycled Construction Resources Institute)
권호 표지
DOI QR코드

DOI QR Code

FA를 혼입한 콘크리트의 온도 영향을 고려한 강도 및 염화물 확산성 평가

Evaluation of Strength and Chloride Diffusion in Concrete with FA Considering Temperature Effect

  • 양근혁 (경기대학교 건축공학과) ;
  • 권성준 (한남대학교 토목환경공학과)
  • Keun-Hyeok Yang (Department of Architectural Engineering, Kyonggi University) ;
  • Seung-Jun Kwon (Department of Civil and Environmental Engineering, Hannam University)
  • 투고 : 2023.01.18
  • 심사 : 2023.03.03
  • 발행 : 2023.03.30
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

UAE 지역에 시공되는 원전구조물의 노출환경에서 대기 중의 높은 황산염 이온 및 해안의 높은 염화물 이온에 의한 열화를 고려할 필요가 있다. 본 연구에서는 연평균 38 ℃ 이상의 높은 온도에 따른 확산성과 강도의 영향을 평가하기 위해 두가지 강도 등급(40 MPa 및 27 MPa) 및 두 가지 양생/확산 온도 조건(20 ℃ 및 50 ℃)을 고려하였다. 초기 양생 온도가 높은 경우, 7일 전 초기재령에서는 압축강도가 고온 양생에서 크게 발현하였으나, 28일 재령에서는 20 ℃ 양생 온도 조건에서 압축강도가 약간 증가하였다. 염화물 확산의 경우, 강도 평가결과와 다르게 28일 재령에서 초기 양생 온도가 높은 경우, 40 MPa 및 27 MPa 에서 모두 확산계수가 감소하였다. 91일 재령의 경우, 온도의 증가에 따른 확산성의 증가와 재령 효과에 의한 확산성의 감소가 동시에 발생하였다. 재령 28일에 20 ℃로 양생 및 확산 실험을 한 결과에 비하여, 재령 91일에 50 ℃로 양생 및 확산 실험을 한 경우, 재령의 증가에 따라 40 MPa에서는 76.2 % 수준으로, 27 MPa 에서는 85.4 % 수준으로 확산계수가 감소하였다.

For the nuclear power concrete plant structures in the UAE, it is necessary to consider the deterioration from high sulfate ions in the atmosphere and high chloride ions from the coast. In this study, two strength grade concrete mixture (40 MPa and 27 MPa) and two curing/diffusion temperatures (20 ℃ and 50 ℃) were considered for evaluating the temperature effects on diffusion and strength due to high average temperature above 38 ℃ a year in UAE. When the initial curing temperature was high, the compressive strength increased in high-temperature curing to 7 days, but the strength slightly increased in the 20 ℃ curing condition at 28 days. Regarding diffusion test, unlike the compressive test results, reduced chloride diffusion coefficients were evaluated both in 40 MPa and 27 MPa grade at 28 days. In the case of 91 days of curing, an increase in diffusivity due to high temperature and a decrease in diffusivity due to age effect occur simultaneously. Compared to the results of the curing and diffusion tests at 20 ℃ and 28 days, when the curing and diffusion tests were conducted at 50 ℃ in 91 days, the diffusion coefficients decreased to 76.2 % in 40 MPa grade and 85.4 % in 37 MPa grade with increasing curing period, respectively.

키워드

과제정보

이 논문은 2022년도 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. NRF-2022M2E9A3091898).

참고문헌

  1. ACI 304.3R-96. (1996). Heavyweight Concrete: Measuring, Mixing, Transporting, and Placing, ACI Committee Report, USA, 1-8.
  2. ACI 211.1-91. (2009). Standard Practice for Selecting Proportions for Normal, Heavyweight, and Mass Concrete, ACI Committee Report, USA, 1-7.
  3. Broomfield, J.P. (1997). Corrosion of Steel in Concrete: Understanding, Investigation and Repair, E&FN, London, 1-15.
  4. Bruck, P.M., Esselman, T.C., Elaidi, B.M., Wall, J.J., Wong, E.L. (2019). Structural assessment of radiation damage in light water power reactor concrete biological shield walls, Nuclear Engineering and Design, 350, 9-20. https://doi.org/10.1016/j.nucengdes.2019.04.027
  5. Chun, J H., Ryu, H.S., Yoon, Y.S., Kwon, S.J. (2017). Crack and time effect on chloride diffusion coefficient in nuclear power plant concrete with 1 year curing period, Journal of the Korea Institute for Structural Maintenance and Inspection, 21(6), 83-90.
  6. Field, K.G., Remec, I., Le Pape, Y. (2015). Radiation effects in concrete for nuclear power plants-part I: quantification of radiation exposure and radiation effects, Nuclear Engineering and Design, 282, 126-143. https://doi.org/10.1016/j.nucengdes.2014.10.003
  7. Ishida, T., Iqbal, P.O.N., Anh, H.T.L. (2009). Modeling of chloride diffusivity coupled with non-linear binding capacity in sound and cracked concrete, Cement and Concrete Research, 39(10), 913-923. https://doi.org/10.1016/j.cemconres.2009.07.014
  8. Jung, S.H., Ryu, H.S., Karthick, S., Kwon, S.J. (2018). Time and crack effect on chloride diffusion for concrete with fly ash, International Journal of Concrete Structures and Materials, 12(1), 1-10. https://doi.org/10.1186/s40069-018-0237-8
  9. Kwon, S.J., Na, U.J., Park, S.S., Jung, S.H. (2009). Service life prediction of concrete wharves with early-aged crack: probabilistic approach for chloride diffusion, Structural Safety, 31(1), 75-83. https://doi.org/10.1016/j.strusafe.2008.03.004
  10. KDI. (2010). Become One of the Top 3 Nuclear Export Powerhouses by 2030, https://eiec.kdi.re.kr/publish/naraView.do?cidx=6998.
  11. Kwon, S.J., Ryu, H.S., Cheon, J.H. (2017). Relationship between age and chloride diffusivity in concrete for nuclear power plant considering crack width, Journal of the Korea Concrete Institute, 29(6), 537-543 [in Korean]. https://doi.org/10.4334/JKCI.2017.29.6.537
  12. Matsumura, T., Shirai, K., Saegusa, T. (2008). Verification method for durability of reinforced concrete structures subjected to salt attack under high temperature conditions, Nuclear Engineering and Design, 238(5), 1181-1188. https://doi.org/10.1016/j.nucengdes.2007.03.032
  13. Pomaro, B. (2016). A review on radiation damage in concrete for nuclear facilities: from experiments to modeling, Modelling and Simulation in Engineering, 2016, 4165746.
  14. Saeki, T., Ohga, H., Nagataki, S. (1990). Change in micro-structure of concrete due to carbonation, Doboku Gakkai Ronbunshu, 1990(420), 33-42. https://doi.org/10.2208/jscej.1990.420_33
  15. So, H.S., Choi, S.H., Seo, C.S., Seo, K.S., So, S.Y. (2014). Influence of temperature on chloride ion diffusion of concrete, Journal of the Korea Concrete Institute, 26(1), 71-78 [in Korean]. https://doi.org/10.4334/JKCI.2014.26.1.071
  16. Thamoas, M.D.A., Bamforth, P.B. (1999). Modelling chloride diffusion in concrete: effect of fly ash and slag, Cement and Concrete Research, 29(4), 487-495 https://doi.org/10.1016/S0008-8846(98)00192-6
  17. Thomas, M.D,A., Bentz, E.C. (2002). Computer Program for Predicting the Service Life and Life-cycle Costs of Reinforced Concrete Exposed to Chlorides, Life 365 Manual, SFA, 2-28.
  18. Weatherspark. (2022). https://ko.weatherspark.com.
  19. Yang, K.H., Moon, J.H. (2012). Mix proportions and physical properties of heavy weight concrete for nuclear power plant, The Korea Institute of Building Construction, 12(3), 9-14 [in Korean].
  20. Yang, K.H., Mun, J.S., Kim, D.G., Cho, M.S. (2016). Comparison of strength-maturity models accounting for hydration heat in massive walls, International Journal of Concrete Structures and Materials, 10(1), 47-60. https://doi.org/10.1007/s40069-016-0128-9
  21. Yang, K.H., Singh, J.K., Lee, B.Y., Kwon, S.J. (2017). Simple technique for tracking chloride penetration in concrete based on the crack and width under steady-state conditions, Sustainability, 9(2), 1-14. https://doi.org/10.3390/su9020282
  22. Yoon, Y.S., Lim H.S., Kwon, S.J. (2019). Evaluation of apparent chloride diffusion coefficient of fly ash concrete by marine environment exposure tests, Journal of the Korea Institute for Structural Maintenance and Inspection, 23(3), 119-126 [in Korean].