Corrosion inhibitors in reinforced concrete structures Part 3 – migration of inhibitors into concrete

Abstract

To prevent and control rebar corrosion in concrete, corrosion inhibitors may be used both as a preventative technique if added to fresh concrete and as a repair system if applied to hardened concrete. In the past six years, an experimental research was performed on both mixed and migrating inhibitors. Effectiveness of mixed inhibitors has been investigated in Part 1: the ability to delay time to corrosion and to reduce corrosion rate has been studied both in the case of chloride-induced corrosion and carbonated concrete. Organic migrating inhibitors were applied to concrete specimens, and their ability to control corrosion was investigated: results are described in Part 2. Results allow to state that the inhibitors are able to delay time to corrosion, while a negligible effect was observed in the reduction of corrosion rate. In the third part, the inhibitor migration into concrete has been analysed in order to quantify inhibitor penetration depth and main penetration mechanism.