FRP column wrapping and corrosion of steel reinforcement in concrete columns - A field study

This paper reports preliminary results of a field investigation regarding the effect of fiber reinforced polymer (FRP) wraps and concrete sealers on the corrosion of rebar in reinforced concrete. The structure under investigation consisted of twelve columns and associated pier caps of an existing bridge in Minneapolis, MN. Six of the structural elements (i.e. columns and associated pier caps) were wrapped with three types of FRP, three of the structural elements were sealed with conventional sealers, and three of the structural elements served as controls. Half of the wrapped structural elements and all of the sealed structural elements were subjected to electrochemical chloride extraction (ECE) prior to being wrapped or sealed. Preliminary results of the ECE process indicated that it was effective in removing some chloride ions from the concrete structures, but its long term effectiveness on inhibiting corrosion is still under investigation.