Numerical Simulation on Rust Distribution of Non-uniform Steel Corrosion Induced by Impressed Current Method

The non-uniform corrosion of steel bars is the main factor affecting the durability of concrete. The cracking pattern of concrete due to corrosion is closely related to the distribution of corrosion products. Research on the thickness distribution of rust layer and cracking pattern of concrete under different influencing factors is of great significance to predict the service life of existing reinforced concrete structures and avoid premature cracking of reinforced concrete structures to be built. Based on the existing research and the non-uniform corrosion test method, this paper studies the thickness distribution model of rust layer on the surface of single and multiple corroded reinforcements under non-uniform corrosion. The electrochemical analysis of the electrified corrosion process was carried out by using the finite element analysis software, and the distribution of current density was obtained. Combined with Faraday’s law, the thickness distribution model of the rust layer on the surface of the steel bar considering the influence of different test parameters under single steel bar and multiple steel bars was established. Using this model, the thickness distribution of corrosion can be designed by controlling different geometric parameters to simulate natural corrosion. Therefore, a relatively short test time can be used to study the crack mechanism.