STUDIES ON CORROSION PREVENTION OF STEEL BARS WITH POLYMER-MODIFIED CEMENT CORROSION INHIBITORS BY ACCELERATED CONCRETE TEST

摘要

When the reinforced concrete structures damaged due to salt pollution, carbonation or a combination of them are repaired, various corrosion-inhibitors are used to prevent the corrosion of steel bars. Especially, polymer-modified cement corrosion inhibitors with nitrite admixtures have been generally used because they can be used easily and they are highly effective for corrosion prevention of steel bars. This study examined the relationship between the repair method with polymer-modified cement corrosion inhibitors and corrosion inhibition effect. After accelerated corrosion test using concrete specimens, corrosion area of steel bars at 3 parts, which were inside the repair mortar and inside the concrete at repair part, and inside the concrete at basis part, were measured. As a result of the test, at repair mortar side of repair part steel bars were not corroded, on the other hand, inside the concrete at basis part and repair part they were corroded. In the repair work of damaged concrete structures, effective repair method is chipping concrete around steel bars at damaged part, coating with polymer-modified cement corrosion inhibitors and restoration of lost section.