MAINTENANCE AND IMPROVEMENT OF DURABILITY OF REINFORCED CONCRETE USING MIGRATING CORROSION INHIBITORS

Abstract

Development and background of migrating corrosion inhibitors (MCI) as well as the significance of maintenance and im-provement of durability in reinforced concrete structure using MCI are introduced. The transfer mechanism of MCI in concrete and the inhibition mechanism of steel bar corrosion are discussed. The design principle of the component and the molecule structure of MCI are suggested. A multiplex inhibitor mainly composed by small molecular ethanolamine having two functional groups and other various components having multi-center of active adsorption with different vapor pressure, which behaviours good migratory per-formance in concrete and long-term stability of film mainly chemisorbed onto the steel surface through the formation of planar five-membered chelate rings with the cation metal has been developed. The introduction of self-repair components and waterproofing components in the inhibitor may lead to the efficacy of repassivation of rusty steel bars in chloride condition and the avoidance of two-way proliferation of volatile components as well as the enhancement of adaptability to the environmental change of reinforced concrete. The token of migratory performance of MCI and appreciation methods of inhibiting efficiency as well as the application research results such as the effect on the durability of reinforced concrete with painting MCI on the hardened concrete surface and the properties of concrete with MCI admixture in the mix are reviewed. The development trend of MCI and the issues to be settled in application techniques of maintenance and improvement of durability of reinforced concrete using MCI are indicated.