Research progress of anticorrosive coatings on concrete surface

Concrete, a typical heterogeneous porous material, is susceptible to the erosion of ionic media in the environment. This erosion leads to the corrosion of concrete and its internal steel bars, consequently affecting the performance of concrete structures and shortening their service life. Among various protective measures, the application of surface anti-corrosion coatings stands out as the most economical and effective method to prevent concrete corrosion and extend the service life of concrete structures. This paper systematically summarizes four types of concrete surface anti-corrosion coatings: surface film-forming, pore-sealing, hydrophobic impregnation, and multi-functional surface treatment coatings. The protection mechanism, corrosion resistance, and existing problems and shortcomings of each coating are discussed. The influence of different modification methods on the enhancement effect of anti-corrosion coatings on concrete surfaces is analyzed emphatically: organic/inorganic composite coatings can achieve complementary advantages and significantly improve the overall performance of coatings. The low polarity of organic silicon and organic fluorine reduces the surface energy of the modified polymer, thereby significantly improving the hydrophobicity and chemical stability of the coating. Adding nanoparticles can improve the mechanical properties and durability of coatings. The construction of special nanostructures can improve the agglomeration of nanoparticles and enhance the hydrophobicity of coatings. Looking forward, the focus of research is on developing efficient, safe, low-cost, and adaptable concrete surface anti-corrosion coatings. This includes exploring the combination of waterborne protective coatings and renewable materials, nano-composite modified new coatings and self-healing coatings.