Title:
Study on Allowable Coating Damage of Epoxy-Coated Reinforcing Bars
Author(s):
Takashi Miura, Hirofusa Itabashi, and Ichito Iwaki
Publication:
Materials Journal
Volume:
94
Issue:
4
Appears on pages(s):
267-272
Keywords:
allowable coating damage; corrosion; corrosive condition; epoxy-
coatings; reinforcing bars;
DOI:
10.14359/308
Date:
7/1/1997
Abstract:
The usage of epoxy-coated reinforcing bars is thought of as one of the most effective methods for protecting reinforced concrete structures from corrosion damages. However, the coating surface may sustain damages during the handling of the epoxy-coated reinforcing bars. This study is to examine the effects which flaws generated on the coating provide to the corrosion of epoxy-coated reinforcing bars. At first, in order to determine the detailed laboratory testing program, two field tests were performed. In the laboratory test, the epoxy-coated reinforcing bars with flaws of various sizes were embedded in concrete specimens and the area of corrosion on the bars had been observed for 400 days. As a result, the epoxy-coated reinforcing bars showed much higher preventive ability under corrosive conditions than normal reinforcing bars, even if some flaws on the coating were found. However, we suggest that under severe corrosive conditions, the size of a flaw should not exceed 1 mm2 for both a 2 cm and a 4 cm of cover and the total area of flaws should not exceed 0.013 percent of the coating surface for a 2 cm of cover and 0.054 percent for a 4 cm of cover, respectively.