한국구조물진단유지관리공학회 논문집 (Journal of the Korea institute for structural maintenance and inspection)

  • 제28권4호
  • /
  • Pages.21-27
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  • 2024
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  • 2234-6937(pISSN)
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  • 2287-6979(eISSN)
한국구조물진단유지관리공학회 (Korea Institute for Structural Maintenance Inspection)
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염소-수산화이온 비율을 고려한 촉진 부식환경에서 텐던의 부식전류 변화

Changes in Corrosion Density of Tendon Under Accelerated Corrosive Condition Considering Chloride-hydroxide Concentration

  • 방자호 (한남대학교 건설시스템공학과) ;
  • 이현우 (한남대학교 건설시스템공학과) ;
  • 권성준 (한남대학교 건설시스템공학과)
  • Ja-Ho Bang ;
  • Hyeon-Woo Lee ;
  • Seung-Jun Kwon (Department of Civil and Environmental Engineering, Hannam University)
  • 투고 : 2024.05.24
  • 심사 : 2024.07.04
  • 발행 : 2024.08.31
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초록

본 연구에서는 염화물 이온과 수산화이온의 변화에 따른 텐던의 부식전류를 평가하였다. 촉진부식환경을 위해 콘크리트 대신 젖은 모래를 사용하였으며, 3 수준의 염화물 농도(0.0, 0.125, 0.25 mol/l)와 3수준의 [Cl-]/[OH-]비 (0.3, 0.6, 0.9)를 고려하여 실험을 진행하였다. 텐던의 부식전류는 0.0 mol/l에서 5.13 µA/cm2으로 평가되었으며, 염화물 농도의 증가에 따라 부식전류도 증가하였다. 또한 0.125 mol/l이상에서는 큰 차이가 발생하지 않았다. 동일한 농도(0.125 mol/l)에서 [OH-]를 증가시켰을 때, 부식전류는 선형적으로 감소하였으며, [OH-]의 증가는 높은 염화물 농도에서도 부식전류 제어에 효과적임을 알 수 있다. 특히 측정된 부식량은 0.0 mol/l의 조건보다 낮은 부식량을 나타내었다. 또한 실험값의 최대값과 최소값을 이용하여 실험결과를 정규화하였으며, 이를 통하여 부식전류와 영향인자간의 상관성을 분석하였다.

In this study, the corrosion density of tendon was evaluated with changing chloride and hydroxide ions. To simulate an accelerated corrosive environment, wet sand was used instead of concrete, and the tests were conducted considering three levels of chloride concentration (0.0, 0.125, and 0.250mol/l ) and three [Cl-]/[OH-] ratios (0.3, 0.6, and 0.9). The corrosion density was measured to 5.13 µA/cm2 at 0.0mol/l and increased with the chloride concentration. Additionally, no significant differences were observed over 0.125mol/l of chloride concentration. When [OH-] increased with a given chloride concentration (0.125mol/l), the corrosion density decreased linearly, showing effective control of corrosion density even at high chloride concentrations. Notably, the measured corrosion amounts were lower than those under of 0.0mol/l condition. Furthermore corrosion density and influencing parameters were normalized with the maximum and minimum results, and the relation between them was analyzed.

키워드

과제정보

본 연구는 정부의 지원으로 한국연구재단 중견연구자지원사업의 지원을 받아 수행되었으며 이에 감사드립니다(NRF-2020R1A2C2009462).

참고문헌

  1. Arya, C., Buenfeld, N. R., and Newman, J. B. (1990), Factors influencing chloride-binding in concrete, Cement and Concrete Research, 20(2), 291-300.
  2. ASTM C876-09. (2009), Standard Test Method for Corrosion Potentials of Uncoated Reinforcing Steel in Concrete, American Society of Testing and Materials.
  3. Broomfield, J. P. (1997), Corrosion of steel in concrete: Understanding, Investigation and Repair, E & FN, London, 1-15.
  4. China, S. A. O. T. (2007), Common portland cement, China Architecture and Building Press: Beijing, China.
  5. DA, H. (1967), Steel corrosion in concrete: how does it occur, Materials Protection, 6, 19-23.
  6. EN 206, B. S. (2013), Concrete-Specification, performance, production and conformity, British Standards Institution, Her Majesty Stationery Office, London, United Kingdom.
  7. Gouda, V. K. (1970), Corrosion and corrosion inhibition of reinforcing steel: I. Immersed in alkaline solutions, British Corrosion Journal, 5(5), 198-203.
  8. Japan Society of Civil Engineering (JSCE), (2002), Concrete Library 109: Proposal of the Format for Durability Database of Concrete.
  9. Kwon, S. J., Na, U. J., Park, S. S., and 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.
  10. Lee, B. Y., Koh, K. T., Ismail, M. A., Ryu, H. S., and Kwon, S. J. (2017), Corrosion and strength behaviors in prestressed tendon under various tensile stress and impressed current conditions, Advances in Materials Science and Engineering, 2017(1), 8575816.
  11. Lee, K. M., Yoon, Y. S., Yang, K. H., Yoo, B. Y., and Kwon, S. J. (2022), Corrosion Behavior in RC Member with Different Cover Depths under Cyclic Chloride Ingress Conditions for 2 Years, Applied Sciences, 12(24), 13002.
  12. Lee, S. K., Zielske, J. (2014), An FHWA special study: post-tensioning tendon grout chloride thresholds.
  13. Luping, T., and Nilsson, L. O. (1993), Chloride binding capacity and binding isotherms of OPC pastes and mortars, Cement and Concrete Research, 23(2), 247-253.
  14. Oh, B. H., Jang, S. Y., and Shin, Y. S. (1999), Corrosion Characteristics of Steel Reinforcements induced by Internal Chlorides in Concrete and determination of Chloride thresholds, Journal of Korea Concrete Institute, 11(3), 193-202 (in Korean).
  15. Permeh, S., Vigneshwaran, K. K., and Lau, K. (2016), Corrosion of post-tensioned tendons with deficient grout.
  16. Podolny Jr, W. (1992), Corrosion of prestressing steels and its mitigation, PCI Journal, 37(5), 34-55.
  17. Rasheeduzzafar. (1992), Influence of cement composition on concrete durability, ACI Materials Journal, 89(6), 574-586.
  18. Ryu, H. S., Park, J. S., and Kwon, S. J. (2017). Relationship between half cell potential and corrosion amount considering saturated cover depth and W/C ratios in cement mortar, Journal of the Korea Institute for Structural Maintenance and Inspection, 21(3), 19-26 (in Korean).
  19. Sandberg, P. (1999), Studies of chloride binding in concrete exposed in a marine environment, Cement and Concrete Research, 29(4), 473-477.
  20. Saraswathy, V., Lee, H. S., Karthick, S., and Kwon, S. J. (2018), Stress corrosion behavior of ungrouted pretensioned concrete beams, Advances in Materials Science and Engineering, 2018, 1-11.
  21. Thangavel, K., and Rengaswamy, N. S. (1998), Relationship between chloride/hydroxide ratio and corrosion rate of steel in concrete, Cement and concrete Composites, 20(4), 283-292
  22. Thomas, M. D. A., and Bentz, E. C. (2002), Computer program for predicting the service life and life-cycle costs of reinforced concrete exposed to chlorides, Life365 Manual, SFA, 12-56.
  23. Thomas, M. D., and Bamforth, P. B. (1999), Modelling chloride diffusion in concrete: Effect of fly ash and slag, Cement and Concrete Research, 29(4), 487-495.
  24. Yoon, Y. S., and Kwon, S. J. (2022), Relationship Analysis between Half Cell Potential and Open Circuit Potential Considering Temperature Condition, Journal of the Korean Recycled Construction Resources Institute, 10(1), 124-132 (in Korean).
  25. Yuan, Q., Shi, C., De Schutter, G., Audenaert, K., and Deng, D. (2009), Chloride binding of cement-based materials subjected to external chloride environment-a review, Construction and Building Materials, 23(1), 1-13.