Title: Study on Durability of a Repaired Concrete Structure in Tokyo Bay

Author(s): P. Kudoh, A. Hirotani, A. Moriwake, and M. Yasuda

Publication: Symposium Paper

Volume: 128

Issue:

Appears on pages(s): 1293-1308

Keywords: chlorides; coatings; corrosion; cracking (fracturing); deterioration; durability; field tests; inspection; jetties; permeability; reinforcing steels; repairs; General

DOI: 10.14359/3848

Date: 11/1/1991

Abstract:
Efficiency of repairs conducted for a jetty damaged by chloride salt attack in Toyko Bay was investigated by field and laboratory tests after five years of repair. Investigation results on durability of surface coatings, chloride ion concentration in concrete, and corrosion of reinforcing bars are presented. Visual inspection, and elasticity or crack bridging ability and adhesion strength to concrete indicated that the durability of surface coatings is sufficient. There is no significant difference in distribution of chloride ion concentration in coated concrete before and after repairing. Dispersion of chloride ion in surface coated concrete was numerically analyzed and the results show that the surface coatings decrease the existing chloride content in surface area as the chloride ions disperse into deeper area by degrees. Reinforcing steels in the coated concrete were found predominantly to be in sound condition, except some did show corrosion where the chloride ion content exceeds a critical value. This investigation also demonstrates the importance of maintenance after repair.