矿井直流电法勘探中的巷道影响

ROADWAY INFLUENCE ON ELECTRICAL PROSPECTING IN UNDERGROUND MINE

提出井下稳恒电流场边界元法正演模型，并引入巷道影响因子函数，用以研究巷道空间对周围电流场分布的影响．数值模拟结果表明，巷道影响与电极和巷道的相对位置有关，导致巷道对底板测深类曲线的影响与对层测深曲线的影响不同；由于巷道影响因子是供电电极距的非线性函数，所以在测深类曲线的定量解释中应考虑巷道影响，而解释矿井电剖面曲线时则不需考虑巷道影响；此外，巷道几何尺寸、围岩导电性对巷道影响因子的大小和变化特征起着决定性作用．

A boundary element model for underground DC field, and the roadway influencing factor (RIF) function are proposed, which can be used to simulate or illustrate the influence of roadway space on the surrounding current field. Modeling results show that RIF is concerned with the relative positions between electrode and roadway. It leads the influence of roadway space on floor sounding curve is different from that on seam sounding curve. As RIF is the non linear function of the distance between current electrodes, the roadway effect must be taken account in the quantitative interpretation of measurements of electrical sounding in underground mine, but it isnt needed in interpreting underground mine electrical profiling curve. Moreover, the parameters of roadway space and the conductivity of its surrounding rock have a decisive influence on the value and characteristic of RIF.