Study On Interference Of Subway Stray Current On Buried Metal Pipelines And Research On Protection

With the development of national economy and the expansion of urban scale,many cities have begun to consider reducing the traffic pressure through subway construction.Subway operating lines and buried metal oil and gas pipelines often have long-distance parallel and intersecting sections in the location,which in turn causes the problem of subway stray current interference with buried metal pipelines.Therefore,it is necessary to study interference laws and protective measures.At present,the related research on the stray current of subways at home and abroad mainly focuses on the theoretical modeling of traction systems and the construction of metal corrosion test benches to study the corrosion laws of metals under AC and DC interference.In order to study the interference of subway stray current on buried metal pipelines,based on the existing research,the thesis calculates the theoretical calculation of the stray current distribution of buried metal pipelines with a single insulation damage point.After that,the subway power supply model and pipeline model were established through the HIFREQ module in CDEGS software.CDEGS software is used to simulate the established model to analyze the effect of DC power supply voltage level,DC power supply method,rail longitudinal resistance,rail-to-ground transition resistance,drainage network input,drainage network depth,power supply interval length,soil resistivity,the length of the pipeline,the parameters of the pipeline anti-corrosion layer,the location and direction of the pipeline and other factors on the voltage along the rail,the leakage current of the rail to study the stray current interference of the pipeline and put forward suggestions from the perspective of safe operation of the subway system and pipeline protection.By changing the train position in the dynamic simulation,the influence of the entire train running process on the safety parameters of the rails and pipes is studied.Then,according to the interference law obtained,specific protective measures are put forward and verified by simulation.Finally,a three-magnet saturation magnetometer probe array was designed to perform non-excavation detection of stray currents in buried metal pipes,and the principle was explained.