基于三维有限元法的巷道影响特征

Impact characteristics of roadway based on 3D finite element method

在矿井瞬变电磁法探测中,巷道空间对探测结果存在影响,不利于探测资料的解释。采用三维有限元法,通过建立地质模型模拟了有无巷道时瞬变电磁场的分布情况,绘制了10 us和0.1 ms时刻有无巷道以及巷道不同长度和高度下XOZ平面磁场强度等值线分布图。结果表明:磁场在高阻区扩散速度比低阻区慢;巷道长度的变化对巷道长度方向磁场分布影响较大;巷道高度的变化对巷道上下方磁场分布影响较大。巷道空间在早期对磁场分布影响较大,晚期则影响不大,这为探测资料异常的解释提供了理论依据。

In the transient electromagnetic detection in mine, the results of the detection are affected by the road-way space, which is not conducive to the interpretation of the results of detection. The 3D finite element method was employed in the study to simulate the impact characteristics of roadway by establishing geological model and the distributions of transient electromagnetic field when there exists roadway or not, and then, the distribution of contour of the magnetic field intensity at different time such as 10？s and 0.1 ms was drawn. The results showed that the spread of magnetic field in high resistance area was slower than that in low resistance area, changes of the length of roadway had great impact on the distributions of the magnetic field along its length, and changes of the height of roadway affected the distributions of the magnetic field along its height. The roadway space had great impact on the distribution of magnetic field in the early time and small impact in the late time, which provided theoretical basis for the interpretation of the results of the detection.