Abstract
There are a lot of parts damaged with the corrosion which induced by chloride ions in the antifreeze agent, mainly at the bridge-girder end of the expressway in Hokuriku region. Firstly in this paper, the progress of this corrosion mechanism at the double reinforcing bars was clarified experimentally. Next, based on the result, "Combined Corrosion Control Method" was proposed as an effective repair method. The feature of this method was the combination of an advantage of the electrolytic anticorrosion using the sacrificial anode (zinc) and an advantage of the patch repair using mortar with the corrosion inhibitor of high concentration. That is, the actual situation of the chloride induced corrosion by the antifreeze agent at the RC bridge was understood. Also, for the double reinforcing bar whose damages were most, the mechanism of the deterioration progress was cleared. Additionally, the effect of a new repair method was estimated, and a cost for the practical use was calculated. As a result, it could be confirmed that "Combined Corrosion Control Method" has efficiency as a repair method for chloride inducing corrosion by the antifreeze agent.
