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

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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Changes in Corrosion Density of Tendon Under Accelerated Corrosive Condition Considering Chloride-hydroxide Concentration

염소-수산화이온 비율을 고려한 촉진 부식환경에서 텐던의 부식전류 변화

  • 방자호 (한남대학교 건설시스템공학과) ;
  • 이현우 (한남대학교 건설시스템공학과) ;
  • 권성준 (한남대학교 건설시스템공학과)
  • Received : 2024.05.24
  • Accepted : 2024.07.04
  • Published : 2024.08.31
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Abstract

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.

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.

Keywords

Acknowledgement

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

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