AN EXPERIMENTAL STUDY ON RELATIONSHIP BETWEEN CHLORIDE CONTENT IN MORTAL AND PASSIVITY CONDITION OF EMBEDDED STEEL BAR

モルタル中の塩分含有量と埋設鉄筋の不動態の状態の関係に関する実験的考察

Electrochemical test method of embedded steel bar in concrete is being developed. Electrochemical properties of steel in concrete are affected by various factors. In this study, the influence of water-cement ratio of mortar and chloride ion content on the half-cell potential, polarization resistance and polarization curve in mortar containing certain amount of chloride ion are examined.<br/>Main results obtained in this study are as follows, (1）Half cell potential was decreased linearly proportional to the increment in chloride ion contents. （2）Polarization resistance quickly decreased at around 0.4％-cement chloride ion content in mortar, （3）The passivity grade quickly decreased from the grade 4 to the grade 3 at around 0.4％-cement chloride ion content in mortar. （4）Half cell potential can indicate the environmental condition around the steel bar. （5）Surface condition of steel bar can be estimated by polarization resistance or polarization curve measurement.本研究では、腐食発生限界塩化物イオン含有量近傍の塩分を含むモルタルにおいて、水セメント比および塩分量が異なる場合の自然電位、分極抵抗および分極曲線等の電気化学的特性値を実測した。その結果、自然電位はコンクリート中の塩化物イオン量の増加に対して線形的かつ連続的に低下する傾向を示し、鉄筋周囲の環境の変化に対応していることが確認された。分極抵抗およびアノード分極曲線より判定される不動態グレードは塩化物イオン量が0.3％～0.4％-cement近傍において大きく変化する傾向を示し、鉄筋表面の不動態皮膜の破壊が生じていることが確認された。このことから、不動態皮膜の破壊が開始するする塩分量は、現在腐食発生限界塩分量とされる0.4％-cementとほぼ同等か若干小さくなることが示された。

• Record URL:
  https://doi.org/10.14250/cement.66.466
• Record URL:
  https://www.jstage.jst.go.jp/article/cement/66/1/66_466/_pdf
• 
• Summary URL:
  http://scholar.google.com/scholar_lookup?title=AN+EXPERIMENTAL+STUDY+ON+RELATIONSHIP+BETWEEN+CHLORIDE+CONTENT+IN+MORTAL+AND+PASSIVITY+CONDITION+OF+EMBEDDED+STEEL+BAR&author=H.+HAMADA&author=Y.+SAGAWA&author=T.+IKEDA&author=K.+TADA&publication_year=2012
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/09163182
• Authors:
  • HAMADA, Hidenori
  • SAGAWA, Yasutaka
  • IKEDA, Takanori
  • TADA, Kohei
• Publication Date: 2012

Language

• English
• Japanese

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: pp 466-471
• Serial:
  • Cement Science and Concrete Technology
  • Volume: 66
  • Issue Number: 1
  • Publisher: Japan Cement Association
  • ISSN: 0916-3182
  • EISSN: 2187-3313
  • Serial URL: https://www.jstage.jst.go.jp/browse/cement/-char/en
• Publication flags:

  Open Access (libre)

Subject/Index Terms

• TRT Terms: Chloride content; Corrosion; Environmental impacts; Mortar; Polarization; Reinforced concrete; Steel; Water cement ratio
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01522563
• Record Type: Publication
• Source Agency: Japan Science and Technology Agency (JST)
• Files: TRIS, JSTAGE
• Created Date: Apr 22 2014 4:07PM