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A Study on the Durability Improvement of Highway-Subsidiary Concrete Structure Exposed to Deicing Salt and Freeze-Thaw

동결융해 및 제설제에 노출된 고속도로 소구조물 콘크리트의 내구성 개선 연구

  • 이병덕 (한국도로공사 도로교통연구원) ;
  • 최윤석 (한국건설생활환경시험연구원 융합기술본부) ;
  • 김영근 (한밭대학교 건축공학과) ;
  • 최재석 (한밭대학교 건축공학과) ;
  • 김일순 (한밭대학교 건축공학과)
  • Received : 2016.04.11
  • Accepted : 2016.04.26
  • Published : 2016.07.01

Abstract

In the current concrete structure of the highway is still the major problem most of concrete deterioration caused by the freeze-thaw and deicing salt, which is of issues that are not completely resolved. In particular, a single freezing event does not cause much harm, durability of concrete under multi-deterioration environment by repeated freeze-thaw and deicing salt is rapidly degraded and reduce its service life. In this study, the exposure environmental condition according the regional highway points were established. The damage condition and chloride content of the concrete at general and severe environmental exposure condition were also investigated. In addition, the experimental test of chloride ion permeability, scaling resistant and freeze-thaw resistance were carried out to improve the durability of the mechanical placing concrete of subsidiary structure. According to the results of this study, in observation of concrete surface condition, the concrete exposed by severe environmental condition showed broad ranges of damage with high chloride contents. Meanwhile, the water-binder(W/B) ratio and the less water content, and fly ash concrete than the specified existing mix proportion is significantly improved the durability. Also, the optimal mix proportion derived for test is satisfied the strength and air contents, water-binder ratio, and durability criteria of concrete specifications, as well as service life seems greatly improved.

현재 고속도로의 콘크리트 구조물에서 대부분 지속되고 있는 가장 큰 문제는 동결 융해와 제설염에 의해 발생하는 콘크리트 열화이고, 이는 완전하게 해결되지 않은 쟁점사항이다. 특히, 동결융해만이 작용할 때와는 달리 동결 융해와 제설염의 복합열화 환경에서 콘크리트의 내구성능은 급격하게 저하되고 공용수명이 단축된다. 본 연구에서는 지역별 고속도로 구간의 노출환경등급을 수립하고 콘크리트 손상정도와 염화물량을 조사하였다. 또한 기계타설 소구조물 콘크리트의 내구성 향상을 위해 배합조건을 개선한 콘크리트의 염화물 이온 투과성, 박리저항성, 동결 융해 저항성 시험을 수행하였다. 연구결과에 따르면, 특수환경에 노출된 콘크리트 표면의 손상범위가 광범위하게 나타났으며 내부 염화물량 또한 높게 나타났다. 한편, 물-결합재(W/B) 비 및 단위수량을 적게 하고, 플라이애시를 혼합하여 내구성을 개선한 콘크리트는 기존의 배합비 보다 내구성이 크게 향상되었다. 또한 도출한 최적 배합비는 콘크리트 관련 시방서에서 제시하고 있는 강도 및 공기량, 물-결합재 비 등의 기준에 부합하였고, 내구성 기준에 만족할 뿐 아니라 공용수명이 크게 향상될 것으로 판단된다.

Keywords

References

  1. Aneta, N. M. (2013), Water-binder Ratio Influence on De-icing Salt Scaling of Fly Ash Conceretes, Procedia Engineering, 57, 823-829. https://doi.org/10.1016/j.proeng.2013.04.104
  2. ASTM (2012), Standard Test Method for Acid-Soluble Cholride in Mortar and Concrete, C 1152-12, ASTM International.
  3. ASTM (2012), Standard Test Method for Electrical Indication of Concrete's Ability to Resist Chloride Ion Penetration, C 1202-12, ASTM International.
  4. ASTM (2012), Standard Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals, C 672-12, ASTM International.
  5. Choi, Y. S., Jang, P. S., Choi, J. S., Kim, Y. G., and Yang, E. I. (2014), A Comparative Study of Evaluation and Test Methods for Effects of De-icing Salts on Concrete Freeze-Thaw Resistance, Proceedings of the Korea Institute for Structural Maintenance and Inspection Conference, 18(2), 308-310.
  6. Choi, Y. S., Kim, G. R., Kim, M. Y., and Yang, E. I. (2006), Characteristics of Chloride Penetration with Deicer Types, Proceedings of the Korea Concrete Institute Conference, 18(2), 549-552.
  7. Choi, Y. S., Won, M. S., Yi, S. T., and Yang, E. I. (2012), Characteristics of Pore Structure and Chloride Penetration Resistance of Concrete Exposed to Freezing-Thawing, Journal of the Korea Institute for Structural Maintenance and Inspection, 16(6), 73-81. https://doi.org/10.11112/jksmi.2012.16.6.073
  8. Choi, Y. S., Yi, S. T., Kim, M. Y., Jung, W. Y., and Yang, E. I. (2014), Effect of Corrosion Method of the Reinforcing Bar on Bond Characteristics in Reinforced Concrete Specimens, Construction and Building Materials, 54, 180-189. https://doi.org/10.1016/j.conbuildmat.2013.12.065
  9. Chung, J. S., Kim, B. H., and Kim, I. S. (2014), A Case Study on Chloride Corrosion for the End Zone of Concrete Deck Subjected to De-icing Salts Added Calcium Chloride, Journal of the Korean Society of Safety, 29(6), 87-93. https://doi.org/10.14346/JKOSOS.2014.29.6.087
  10. Doh, Y. S., Lee, B. D., Choi, K. S., and Kim, K. W. (2008), Evaluation of Deicing Performance and Effects of Deicers of the Winter Season, Journal of the Korean Society of Road Engineers, 10(3), 149-158.
  11. Gintautas, S., Dzigita, N., Giedrius, G., Marija, V., and Erika B. (2013), The Cement Type Effect on Freeze-Thaw and Deicing Salt Resistance of Concrete, Procedia Engineering, 57, 1045-1051. https://doi.org/10.1016/j.proeng.2013.04.132
  12. Kim, H. S., Kim, J. C., and Rhee, J. Y. (2014), Field Investigation of Deterioration of Concrete on Road Structures by De-icing Salts, Proceedings of the Korea Concrete Institute Conference, 26(2), 489-490.
  13. Korea Concrete Institute (2009), Standard Specifications for Concrete Construction, Korea Concrete Institute.
  14. Korea Concrete Institute (2012), Specifications for Structural Concrete, Korea Concrete Institute.
  15. KS F 2405 (2010), Standard test method for compressive strength of concrete, Korean Agency for Technology and Standard. 1-6.
  16. KS F 2456 (2013), Standard test method for resistance of concrete to rapid freezing and thawing, Korean Agency for Technology and Standard. 1-11.
  17. Kwon, S. J. (2015), Evaluation of Service Life in RC Column under Chloride Attack through Field Investigation: Deterministic and Probabilistic Approaches, Journal of the Korea Institute for Structural Maintenance and Inspection, 19(5), 67-74. https://doi.org/10.11112/jksmi.2015.19.5.067
  18. Lee, B. D. (2010), Effect of Air Contents, Deicing Salts, and Exposure Conditions on the Freeze-Thaw Durability of the Concrete, Journal of the Korean Society of Road Engineers, 12(2), 107-113.
  19. Lee, B. D., Yun, B. S., Lee, J. K., and Chung, Y. H. (2005), Evaluation of the Deicing Performance and Concrete Structure Effect with Various Deicing Chemicals, Journal of the Korean Society of Road Engineers, 7(4), 113-123.
  20. Lee, H. G., Oh, H. S., Sim, J. S., and Shim, J. W. (2015), An Experimental Study on Evaluation Methods for Scaling Resistance of Cement Concrete Pavement, Journal of the Korea Institute for Structural Maintenance and Inspection, 19(3), 30-38. https://doi.org/10.11112/jksmi.2015.19.3.030
  21. Liu, Z., and Hansen, W. (2015), Freezing Characteristics of Air- Entrained Concrete in the Presence of Deicing Salt, Cement and Concrete Research, 74, 10-18. https://doi.org/10.1016/j.cemconres.2015.03.015
  22. Mehta, P. K. (2014), Concrete: Microstructure, Properties, and Materials, McGraw-Hill, 4th Ed.
  23. Neville, A. M. (2012), Properties of Concrete, Prentice Hall, 5th Ed.
  24. Park, S. S., and Jeong, J. W. (2014), A Study of Accelerated Corrosion Test and Chloride Penetration Analysis with Artifical Seawater Immersion Condition, Journal of the Korea Institute for Structural Maintenance and Inspection, 18(1), 93-100. https://doi.org/10.11112/jksmi.2014.18.1.093
  25. Power, T. C. (1958), The Physical structure and Engineering Properties of Concrete, Bulletin 90, Portland Cement Association, Skokie, IL.
  26. Van den Heede, P., Furniere, P., and De Belie, N. (2013), Influence of Air Entraining Agents on Deicing Salt Scaling Resistance and Transport Properties of High-Volume Fly Ash Concrete, Cement and Concrete Composites, 37, 293-303. https://doi.org/10.1016/j.cemconcomp.2013.01.005
  27. Yang, E. I., Kim, M. Y., Lho, B. C., and Kim, J. H. (2006), Evaluation on Resistance of Chloride Attack and Freezing and Thawing of Concrete with Surface Penetration Sealer, Journal of the Korea Concrete Institute, 18(1), 65-71. https://doi.org/10.4334/JKCI.2006.18.1.065

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