The Numerical Simulation Of Radial Steel Gate Considering Corrosion Forms

The main forms of the steel corrosion are divided into overall corrosion and local corrosion. the overall corrosion will cause the uniform thinning of the section size and weaken the strength and rigidity of the steel. The local corrosion is mainly refers to non-uniform corrosion, although the quality loss of the local corrosion is smaller than the uniform corrosion, but it can cause the incompactness of the structure and it is much more dangerous. And the corrosion pits produced by pitting and erosion are the most important and the most dangerous forms of corrosion failure. The radial steel gate is an important part of hydraulic structures and its material and special working conditions lead to the characteristics of easy corrosion. Corrosion problem is one of the most important factors that influence the safety of radial steel gate. So it is very important to use the finite element analysis to calculate the influence of corrosion on the working behavior of the radial steel gate.Base on the achievement of the previous, this paper introduces the basic principle of the corrosion of the radial steel gate, the influence factors of corrosion, the detection method and the processing of the data. The finite element modeling methods of solid structure and corrosion pits of the shell structure in engineering practice are summarized. Then the arcticle took large-scale general finite element software ANSYS as the platform, the modeling method of radical steel gate undering consideration of corrosion is mainly studied. The average corrosion thickness method is used to simulate the overall corrosion and to the local corrosion, the simulation of corrosion pits is realized by reducing the thickness of the shell element at a certain node by using ANSYS advanced parametric programming language APDL. Combined with an engineering example, the finite element models of the spillway radical steel gate before and after considering corrosion forms are established and calculated. The effect of corrosion on the static characteristics of radial steel gate was studied. The average corrosion thickness method and the method of considering the corrosion pits’s real forms were simulated and calculated, the results show that by considering the corrosion pits’s real forms has a significant influence on the stress distribution of the gate structures. Combined with the corrosion sensitive parts of the radial steel gate, the influence of corrosion area and corrosion depth on the working behavior of gate were studied, the results show that the increase of the corrosion degree is more affected to the increase of the gate’s stress than just considering the increase of the corrosion depth. The research results can be used to analyze the working behavior of the radial gate in service, and provide effective methods and useful guidance for the daily management of the radial gate and the simulation of corrosion.