Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Relationship between Corrosion in Reinforcement and Influencing Factors Using Half Cell Potential Under Saturated Condition

습윤 상태에서의 반전위를 이용한 철근 부식과 영향 인자 간의 상관성 분석

  • Jeong, Gi-Chan (Department of Civil and Environmental Engineering, Hannam University) ;
  • Kwon, Seung-Jun (Department of Civil and Environmental Engineering, Hannam University)
  • 정기찬 (한남대학교 토목환경공학과) ;
  • 권성준 (한남대학교 토목환경공학과)
  • Received : 2021.04.16
  • Accepted : 2021.06.17
  • Published : 2021.06.30
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Abstract

In this study, the correlation between the influencing factors on corrosion and Half Cell Potential(HCP) measurement was analyzed considering the three levels of W/C ratio, cover depth, and chloride concentration. The HCP increased with enlarged cover depth, so it was confirmed that the increment of cover depth was effective for control of corrosion. Based on the criteria, the case of 60mm cover depth showed excellent corrosion control with under -200mV, indicating increase of cover depth is an effective method for reducing intrusion of external deterioration factors. When fresh water was injected to the upper part of specimens, very low level of HCP was monitored, but in the case that concentrations of chloride were 3.5% and 7.0%, HCP dropped under -200mV. In addition, the case with high volume of unit binder showed lower HCP measurement like increasing cover depth. Multiple regression analysis was performed to evaluate the correlation between the corrosive influence factors and HCP results, showing high coefficient of determination of 0.97. However, there were limitations such as limited number of samples and measuring period. Through the additional corrosion monitoring and chloride content evaluation after dismantling the specimen, more reasonable prediction can be achieved for correlation analysis with relevant data.

본 연구에서는 3가지 수준의 물-시멘트 비, 상부 주입 염수 농도, 피복두께를 고려하여 반전위값과 영향인자들 간의 상관성을 분석하였다. 피복두께가 증가할수록 반전위값이 증가(+ 방향 : 부식 억제)하여 부식 저항성이 증가하는 것을 확인할 수 있었으며 평가 기준에 따르면 피복두께 60mm를 갖는 시편의 경우 비교적 부식이 적게 일어난 것으로 판단된다. 이는 피복두께가 외부 열화인자에 대한 효과적인 방어기구로서 작용한 것이 원인으로 사료된다. 상부 주입 염수 농도가 0%인 경우 모든 경우에서 부식이 발생하지 않는 것으로 판단되지만, 염수 농도 3.5% 및 7.0%의 경우 부식이 진전된 것으로 판단된다. 비교적 높은 단위 결합재량이 확보된 배합에서 부식 저감에 유리한 모니터링 결과가 도출되었으며, 부식 영향인자와 반전위값 간의 상관성을 평가하고자 다중 회귀분석을 수행하였다. 해당 예측식의 결정계수는 0.97로 매우 높은 수준으로 나타났지만 사용한 표본의 수가 제한적이고 특정 시점의 결과만이 이용된 한계점이 존재하였다. 추가적인 모니터링 수행 및 시편 해체 후 관련 데이터와의 상관성 분석을 통해 더욱 합리적인 예측식의 도출이 가능해 질 것으로 사료된다.

Keywords

Acknowledgement

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

References

  1. Broomfield, J.P. (1997). Corrosion of Steel in Concrete: Understanding, Investigation and Repair, E&FN, London, 1-15.
  2. Maekawa, K., Ishida, T., Kishi, T. (2009). Multi-Scale Modeling of Structural Performance, Taylor Fr, 322-325.
  3. Amey, S.L., Johnson, D.A., Miltenberger, M.A., Farzam, H. (1998). Predicting the service life of concrete marine structures: an environmental methodology, ACI Structural Journal, 95(2), 205-214.
  4. European Committee for Standardization(Comite Europeen de Normalisation, CEN) (2000). Eurocode 1: Basis of Design and Actions on Structures; EN-1991; European Committee for Standardization(Comite Europeen de Normalization, CEN): Brussels, Belgium.
  5. Japan Society of Civil Engineering(JSCE) (2007). Standard Specification for Concrete Structures-Design JSCE Guidelines for Concrete 15; Japan Society of Civil Engineering(JSCE): Tokyo, Japan.
  6. Park, S.S., So, B.T. (2016). A study on correlation between accelerated corrosion test and long-term exposure test according to the temperature condition, Journal of the Korean Recycled Construction Resources Institute, 4(2), 203-208 [in Korean]. https://doi.org/10.14190/JRCR.2016.4.2.203
  7. Chung, L., Kim, J.H.J., Yi, S.T. (2008). Bond strength prediction for reinforced concrete members with highly corroded reinforcing bars, Cement and Concrete Composites, 30(7), 603-611. https://doi.org/10.1016/j.cemconcomp.2008.03.006
  8. Lim, Y.C. (2012). A study on the estimation of moisture condition of concrete by resistivity method, Journal of Korea Architecture Institute, 28(12), 69-76 [in Korean].
  9. ASTM C876-09 (2009). Standard Test Method for Corrosion Potentials of Uncoated Reinforcing Steel in Concrete, 1-6.
  10. Song, H.W., Saraswathy, V. (2006). Studies on the corrosion resistance of reinforced steel in concrete with ground granulated blast-furnace slag-An overview, Journal of Hazardous materials, 138(2), 226-233. https://doi.org/10.1016/j.jhazmat.2006.07.022
  11. Kwon, S.J., Park, S.S. (2012). Non destructive technique for steel corrosion detection using heat induction and ir thermography, Journal of the Korea Institute for Structural Maintenance and Inspection, 16(2), 40-48 [in Korean]. https://doi.org/10.11112/jksmi.2012.16.2.040
  12. Baek, S.H., Xue, W., Feng, M.Q., Kwon, S.J. (2012). Nondestructive corrosion detection in RC through integrated heat induction and IR thermography, Journal of Nondestructive Evaluation, 31(2), 181-190. https://doi.org/10.1007/s10921-012-0133-0
  13. Karthick, S., Kwon, S.J., Lee, H.S., Muralidharan, S., Saraswathy, V., Natarajan, R. (2017). Fabrication and evaluation of a highly durable and reliable chloride monitoring sensor for civil infrastructure, RSC advances, 7(50), 31252-31263. https://doi.org/10.1039/c7ra05532c
  14. Karthick, S.P., Muralidharan, S., Saraswathy, V., Thangavel, K. (2014). Long-term relative performance of embedded sensor and surface mounted electrode for corrosion monitoring of steel in concrete structures, Sensor and Actuators B: Chemical, 192, 303-309. https://doi.org/10.1016/j.snb.2013.10.123
  15. Figg, J.W., Marsden, A.F. (1985). Developement of Inspection Techniques for Reinforced Concrete, Offshore Technology Report, OTH 84205.
  16. Jang, S.Y., Yoon, Y.S., Kwon, S.J. (2018). Derivation of optimum GGBFS replacement with durability design parameters, Journal of the Korean Recycled Construction Resources Institute, 6(1), 36-42. https://doi.org/10.14190/JRCR.2018.6.1.36
  17. Thomas, M.D., 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
  18. Rye, H.S., Park, J,S., 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 Korea]. https://doi.org/10.11112/jksmi.2017.21.3.019