Coal Mine Inclined Shaft Advanced Detection Method and Physical Model Test Based on Shield Cutterhead Moving Array Electrodes

Abstract

Using tunnel boring machine (TBM) to construct inclined shafts in coal mines has become the main way for large-scale coal mines to enter deep mining faces. However, some engineering disasters such as water in rush and rock burst will occur when TBM crosses the aquifer and weak broken rock strata. For the sake of efficient tunneling and advanced optimization of the safety plan and supporting measures, it is critically important to detect the anomalous geological conditions in front of the driving face during the service of TBM. Based on the bore-tunneling electrical ahead monitoring (BEAM) system, this paper proposes a coal mine inclined shaft advanced detection method based on shield cutterhead moving array electrodes. First, as the BEAM system cannot image owing to its low utilization rate on spatial distribution information, a diversified excitation and measurement mode with the cutters on the cutterhead as the exciting electrode and measuring electrode is proposed to provide a calculation condition for inversion imaging of the geological condition in front of the driving face. Then, in order to improve the speed of inversion imaging, a virtual grounding electrode equivalent model is proposed to replace the original guard electrode model. Finally, in order to verify the effectiveness of the method, the influence of the virtual grounding electrode on the inversion results at different positions is studied through a physical model test and a numerical inversion test. The results show that the method can better reflect the position of anomalous body.

High-Precision Electrical Impedance Tomography for Electrical Conductivity of Metallic Materials

“…Infrared thermography requires a high level of the external environment and detection equipment, and the detection results are easily affected by the external environment [4]. Zhao et al completed the overdetection of coal mine inclined shafts by measuring the soil conductivity [5,6]. However, the objects studied in these studies were nonmetallic objects or susceptible to environmental influences.…”

Research and application of advanced detection simulation of Electrical resistivity tomography(ERT) based on ANSYS

“…As a result, several geophysical prospecting techniques started to be used (Smee and Bailes. 1986) such as three-dimensional(3D) seismic exploration (Song et al 2019), radio electromagnetic wave penetration technology, ground penetrating radar (GPR) (Tauqeer et al 2014), the 3D ERT (Li et al 2020), the transient electromagnetic method(TEM) (Lin et al 2013;Lin et al 2020), and others (Zhao et al 2019). The increasing scientific evaluation methods promote these geophysical prospecting methods to contribute to the advanced exploration of unfavorable geological bodies (such as water-rich areas) (Lin et al 2022;Liu et al 2023).…”