Initiation of corrosion of reinforcing steel in concrete is
often caused by chlorides. Using a pressurized method for
the purpose of accelerating penetration of sea water into
concrete, the threshold chloride ion concentration for
corrosion of reinforcing steel in Type I portland cement
concrete has been studied in detail. The variables that
have been investigated include water-cement ratio and steel
surface preparation. When corrosion was detected by
electrochemical potential measurement, the test was
terminated; and chloride ion concentration was evaluated. No
correlation between threshold concentration and water-cement
ratio was found. With regard to surface condition, the pre-rusted
steel specimen showed a tendency to corrode at a
lesser chloride ion concentration than for the other preparation
techniques, which were sand blasting and
pretreatment in a saturated calcium hydroxide solution.
The results are presented and discussed within a perspective
of established concrete and corrosion technologies.