环境作用下钢筋锈蚀的探讨

Discussion about Reinforcement Corrosion under Action of Environment

混凝土的碳化机理即酸性气体和水泥水化产物相互作用生成碳酸钙,体积膨胀,造成混凝土保护层鼓起、脱落甚至是完全破坏;氯离子引起钢筋腐蚀机理即氯离子浓度达到一定值时,会破坏混凝土和钢筋在碱性溶液中形成的钝化膜,引起钢筋锈蚀,体积膨胀。Fick第一、第二定律,分别给出了混凝土保护层碳化、氯离子侵蚀的数学模型以及他们的解,从而得出从环境、适当增大钢筋的保护层厚度,采用耐腐蚀的钢筋品种等方面,防止钢筋锈蚀。

Concrete carbonation mechanism was acidic gases and interaction of cement hydration products to generate calcium carbonate and volume expansion,resulting in concrete protective layer muster,being completely destroyed and even falling off. The corrosion mechanism caused by chloride ions was that chlorine ion concentration reached a certain value damaged the passive film concrete formed in alkaline solution of steel bar,causing steel corrosion and volume expansion.Fick first and second law,respectively,gave the mathematical models of the protective layer of concrete carbonation and chloride ion erosion of and their solutions,then preventing steel bar corrosion from environment,increases the protective coating thickness of steel bar and use corrosion-resistant steel grade and so on.