Abstract:Taking the underground geo-electrical resistivity observation device at Pingliang station as an example, this paper analyzed the relationship between the layout of geo-electrical resistivity observation device and the interference of metal pipelines by using the finite element numerical simulation method. The results show that: (1) The influence of metal pipeline perpendicular to the survey line on geo-electrical resistivity observation is significantly less than that parallel to the survey line. The most effective suppression method is to increase the avoidance distance of metal pipeline. (2) When the metal pipeline is set in the center of electrodes, the increase of the buried depth of electrode may not effectively suppress the interference. The effect is significant when the metal pipeline is perpendicular to the survey line direction, but it is not ideal when it is parallel to the survey line direction. (3) The influence of metal pipeline on the underground geo-electrical resistivity observation is relatively complex, which is related to many factors, i.e., the device system (observation polar distance, electrode buried depth), the layered medium electrical structure, and the properties of metal pipeline (conductivity, cross-sectional area, length, distance), etc. The method proposed in this paper can quickly determine the abnormal changes of data, thus having a certain reference significance for anomaly tracking. It can also provide a theoretical basis for the new underground geo-electrical resistivity observation device, so as to improve the observation efficiency of station.
