迁移型阻锈剂在既有混凝土结构中阻锈作用研究

Effect of migration-type rust inhibitor in existing structure concrete on rust prevention

通过内掺氯盐混凝土试件和既有混凝土结构中迁移型阻锈剂的修复试验,结合钢筋自然电位、腐蚀面积率和失重率,综合评价迁移型阻锈剂修复措施的阻锈效果.研究结果表明:涂刷、灌注、复合修复均能起到良好的阻锈效果,其中复合修复阻锈效果最佳;涂刷、灌注修复时,若达不到亚硝酸根离子与氯离子临界摩尔比,会引起宏电池腐蚀,加速钢筋锈蚀;磷酸氢二钠阻锈性能弱于亚硝酸钠,但不发生宏电池腐蚀.

By various repairing experiments of the migration type rust inhibitor in both chloride-containing concrete test blocks and the concrete in existing structures,the rust prevention effect of different repairing measures of the migration type rust inhibitor was determined by rebar natural potential,mass loss degree and corrosion area ration.The results showed that brushing repairing,perfusion repairing,and composite repairing can all achieve good rust-resisting effect,and composite repairing has the best effect on rust prevention;if brushing or perfusion repairing fails,it is unable to reach to the critical molar ratio of nitrite ion to chloride ion and it may cause the macro battery corrodes and accelerate the corrosion of steel bars;the rust resistance of disodium sulphate is weaker than that of sodium nitrite,but it does not cause macro battery corrosion to occur.