地质雷达和高密度电法联合探测底板含水性的应用

Application of GPR and high density electrical method to detect water content of floor

矿井底板富水是影响煤矿安全生产的重大隐患,为准确探查底板的含水性,指导煤矿防治水工作。采用对地质体识别精准的地质雷达和对水反应灵敏的高密度电法进行探测具有探测精度高、解释准确高效的特点。首先分析了地质雷达和高密度电法的基本原理,然后基于地质雷达正演理论,建立了完整地层、溶孔溶洞、裂缝裂隙正演模型,分析各自模型的雷达图像特征;基于高密度电法正演理论,建立了完整地层、高阻、低阻正演模型,在分析各自模型正演响应特征的基础上进一步给出反演结果。数值模拟结果表明地质雷达可根据图像特征来识别地质体,高密度电法可根据高阻、低阻响应特征来判定含水性。最后,在贺西矿四采区东翼底抽巷2号钻场处底板进行实际探测,准确探测了底板下方30 m范围内存在两处含水异常,一处为含水裂隙裂缝发育带,另一处为一富水带。经钻探实际验证,探测所显示的含水异常体与实际对应较好,结果表明了矿井地质雷达和高密度电法联合探测可以准确有效地探测底板含水性。

The rich water in the mine floor is a major hidden danger that affects the safety production of coal mines.The use of geological radar for accurate identification of geological bodies and high-density electrical methods sensitive to water has the characteristics of high detection accuracy,accurate interpretation and high efficiency.Firstly,the basic principles of geological radar and high-density electrical method were analyzed,and then based on the forward modeling theory of GPR,the forward modeling of complete strata,dissolved pores and caves,karst caves and fractures were established,and the radar image characteristics of each model were analyzed.Based on the forward modeling theory of HDE,a complete formation,high-resistance,and low-resistance forward modeling models were established,and the in⁃version results were further given based on the analysis of the forward modeling response characteristics of the respective models.The re⁃sults of numerical simulation show that GPR can identify the geological body according to image characteristics,and high-density electrical method can determine the water content according to the high-resistance and low-resistance response characteristics.Finally,the actual detection was carried out at the floor of the east wing of the fourth mining area of Hexi mine,and two water bearing anomalies were detected within 30 m below the bottom of the bottom of the floor.One was the water bearing fracture development zone,and the other was a water rich zone.The results show that the combined detection of mine GPR and high-density electrical method can accurately and effectively de⁃tect the water content of the floor.