Review of Research on Mechanical Properties of Steel Structure Under Atmospheric Environment Corrosion

Steel structureshave been widely applied because of its light weight, high strength, convenient construction, good plasticity and seismic performance. In recent decades, with the sharp increase in domestic steel production and variety, steel structures have not only been applied to traditional industrial plants, but also gradually applied to high-rise, super high-rise and long-span structures. However, steel structure has an obvious disadvantage, that is, it is easy to corrode, and the steel structures exposed to the atmospheric environment will form a thin liquid film on the surface of the steel, which will corrode the structure during the alternating wet and dry process. With the acceleration of modern industrialization in China, environmental problems have become increasingly prominent, and steel corrosion is most severe in acidic atmospheres rich in SO2 and in offshore atmospheres rich in Cl-. Corrosion of steel not only causes huge economic losses, but also affects the safety and stability of the structures. Because of corrosion, the effective cross-sectional areas of the components decrease, the strength and ductility decrease, and the rust pits generated by the uneven corrosion will cause stress concentration, etc. When the dynamic load acts, these phenomena will cause brittle fracture of the steel and affect the fatigue strength, increasing the probability of steel structure risk. The deterioration of steel structures performance under atmospheric environmental corrosion has attractedwide attention. At present, researches on atmospheric corrosion of steels by scholars at home and abroad mainly focus on: I. atmospheric corrosion mechanism and influencing factors of steels, Ⅱ. different atmospheric corrosion test methods and their correlation, Ⅲ. research on atmospheric corrosion depth prediction model of steels (Although a variety of models have been established at present, it is necessary to study a predictive model with relatively simple expression and high precision), Ⅳ. mechanical properties of steel and steel components under atmospheric corrosion, Ⅴ. the dynamic mechanical properties of steel structures under atmospheric corrosion (It still lack intensive study about this aspect). Accordingly, in order to clarify the influence of atmospheric environment (acid and offshore atmospheric environment) corrosion on the steel structure performance, this article reviews the worldwide researches about atmospheric corrosion of steel structures in recent 50 years, and focuses on the effects of corrosion on the static and dynamic mechanical properties of steel structures under acidic and offshore atmospheric conditions. Firstly, the corrosion mechanism of steel in acidic (rich in SO2) and offshore (rich in Cl-) atmospheres and the influencing factors of atmospheric corrosion are described in detail. Secondly, the atmospheric corrosion test methods of steel and the related research work on the mechanical properties of steel structures under atmospheric corrosion are summarized. Finally, some important issues concerning the research of atmospheric corrosion of steel structures are discussed, and some suggestions for further research are proposed. © 2020, Materials Review Magazine. All right reserved.