Research on simulation and application of mine dipole-dipole advance detection device by direct current method

Advanced detection using the direct current (DC) method in underground coal mines is a primary technique for identifying water-bearing structures ahead of the driving face. Traditionally, a three-pole advanced detection device, based on spherical shell theory, has been widely utilized in field applications. However, recent concerns have been raised by scholars regarding the accuracy and resolution of this device. Moreover, the necessity of using infinite electrodes in underground settings results in low construction efficiency and high costs. To address these issues, this paper proposes a dipole-dipole advanced detection device. We assess the device's detection capabilities through a combination of theoretical research, numerical simulations, and analysis of measured data. Initially, we establish a full-space geoelectric model to simulate the electric field distribution characteristics of a DC dipole source, demonstrating the method's reliability and feasibility for advanced DC detection. We then compare and analyze the detection effects and response characteristics to low-resistance anomalous bodies of both pole-dipole and dipole-dipole devices using uniform and varied full-space geoelectric models. Finally, field tests provided valuable insights into the electrical response characteristics at the front of the excavation tunnel. Using the transient electromagnetic advance detection method for comparative analysis, we identified a low-resistance anomaly located between 5 to 45 meters ahead. This anomaly was subsequently confirmed through drilling. The study concludes that the mine's dipole-dipole DC method effectively identifies low-resistance anomalies in front of the driving head. This method not only offers high detection accuracy and construction efficiency but also saves significant manpower and material resources, highlighting its theoretical significance and practical application value.