Influence Of The Stray Current Corrosion On The Mechanical Performance Of Concrete In The Rail Transit System

With the increase in the construction of railways and the need for transportation by railways,the problem of the influence of a stray current is becoming increasingly clear.The stray current is a practical problem that is difficult to avoid by electrified rail traffic with the return rail as the return line.Stray current can cause corrosion of the lower reinforced concrete members and structures.Unlike natural and natural corrosion,the vast majority of stray current corrosion is the category of corrosion electrochemical nonlinear systems with corrosion rates up to several times or even hundreds of times of natural corrosion,so stray current corrosion is a potential threat to the safety of the train one.In this paper,the effects of stray current on the compressive,flexural and fatigue properties of concrete are studied.The main content about test conditions to control,how many concrete samples were done,and what were the experimental design aspects of the experimental study.The research is aimed at studying the change under the influence of a constant electric current strength when compressing concrete,strength when bending concrete and fatigue strength on concrete compression.To carry out the research,conditions similar to real ones were created under laboratory conditions,in which concrete is tested under the influence of an external electric direct current.Concrete is exposed for a long time to the electric field and mechanical loads under these conditions.To determine the strength of the electric field on the concrete,we used two main factors-the voltage of the current acting on the concrete and the time of exposure of the electric field to the concrete.The test for bending and compressing concrete passes every month for three months.The fatigue test takes place three months from the start of the study.With the increase in the voltage of electricity supplied to the concrete,the destruction of the sample under the influence of corrosion increased.The same effect was observed with an increase in the time of exposure of the concrete to the electric field.But in all cases,changes in strength due to the influence of electricity are small.If we talk about the combined effect of wandering currents and the constant mechanical impact from the railroad to concrete,then the harmful effect on concrete necessarily increases.The effect of the electric field on the fatigue strength of concrete during compression is affected negatively.As the voltage of the electric field increases,the loading time before the destruction of the concrete sample is reduced.The effect of the electric field on the flexural strength and compressive strength of concrete is not clearly observed.The law of change in compressive strength and bending of concrete under the influence of an extra-electric field is not observed.