Corrosion Behavior of Cr-bearing Corrosion Resistant Rebar in Concrete with Chloride Ion Content

  • Tae, Sung Ho (Department of Architecture, Hanyang University)
  • 투고 : 2005.04.13
  • 발행 : 2005.06.30

초록

Conventional studies have focused on the reduction in the water-cement ratio, the use of various admixtures, etc., to ensure the durability of reinforced concrete structures against such deterioration factors as carbonation and chloride attack. However, improvement in the concrete quality alone is not considered sufficient or realistic for meeting the recent demand for a service life of over 100 years. This study intends to improve the durability of reinforced concrete structures by improvement in the reinforcing steel, which has remained untouched due to cost problems, through subtle adjustment of the steel components to keep the cost low. As a fundamental study on the performance of Cr-bearing rebars in steel reinforced concrete structures exposed to corrosive environments, The test specimens were made by installing 8 types of rebars in concretes with a chloride ion content of 0.3, 0.6, 1.2, 2.4 and $24kg/m^3$. Corrosion accelerated curing were then conducted with them. The corrosion resistance of Cr-bearing rebars was examined by measuring crack widths, half-cell potential, corrosion area and weight loss after 155 cycles of corrosion-accelerating curing. The results of the study showed that the corrosion resistance increased as the Cr content increased regardless of the content of chloride ions, and that the Cr-bearing rebars with a Cr content of 5% and 9% showed high corrosion resistance in concretes with a chloride ion content of 1.2 and $2.4kg/m^3$, respectively.

키워드

참고문헌

  1. Matsushita, H. (1999) 'Corrosion measures of a concrete construction and prospect.' cement & concrete, No. 624:1-15
  2. Lee, H. S. (2003) 'An experimental study on the retrofitting effects of reinforced concrete columns damaged by rebar corrosion strengthened with carbon fiber sheets.' Cement and Concrete Research, V. 33:563-570 https://doi.org/10.1016/S0008-8846(02)01004-9
  3. Smith, F.N. & Tullmin, M. (1999) 'Using Stainless Steels as Long-Lasting Rebar Material, Materials Performance.' May:72-76
  4. Rostam, S. (2003) 'Reinforced concrete structures-shall concrete remain the dominating means of corrosion prevention?.' Materials and Corrosion, V. 54:369-378 https://doi.org/10.1002/maco.200390086
  5. Treece, R.A. & Jirsa, J.O. (1989) 'Bond Strength of Epoxy-Coated Reinforcing Bars.' ACI Materials Journal, V. 86, No. 2, March-April:167-174
  6. Miura, T. & Itabashi, H. & Iwaki, I. (1997) 'Study on Allowable Coating Damage of Epoxy-Coated Reinforcing Bars.' ACI Materials Journal, V. 94, No. 4, July-August:267-272
  7. Borges, P.C. & Rincon, O.T. & Moreno, E.I. & Torres-Acosta, A.A. & Martinez-Madrid, M. & Knudsen, A.(2002) 'Performance of a 60-Year-Old Concrete Pier with Stainless Steel Reinforcement.' Materials Performance, October:50-55
  8. Japan Concrete Institute(1987) 'Examination method and criterion about corrosion, corrosion resistance of a concrete construction (plan), JCI, SC1, corrosion evaluation method of steel materials in concrete.' 1-2
  9. ASTM C 876-80(1981) 'Standard test method for Half cell Potentials of reinforcing steel in concrete,' 554-560
  10. Stainless steel association(1984) 'Basics knowledge of stainless steel,' 2
  11. Uhlig, H.H. (1953) 'Corrosion Handbook,' 150
  12. Japan Society of Civil Engineers (2000) 'Concrete standard specification (construction). -durability collation type-'