覆岩破坏直流电场特征数值计算

THE NUMERICAL CALCULATION OF DIRECT CURRENT FIELD CHARACTER OF OVERBURDEN FAILURE

覆岩破坏引起稳态电场特征发生变化，其主要变化的电性参数是电阻率。通过建立煤层开采前后覆岩电性参数变化的数学模型，利用二维有限单元法进行覆岩破坏前后电阻率分布的数值模拟。计算结果表明：电阻率的变化主要由覆岩破坏后产生裂隙带和冒落带的岩石电性特征变化引起。

The overburden failure causes the changes of the constant electric field,and the resistivity is the main parameter in these changes.2D finite element method(FEM)is used to simulate the resistivity distribution of overburden by building the mathematics models of the overburden electrical parameter changes.The calculation indicates that the resistivity varies with the electrical character of the rock in cracked zone and caving zone caused by overburden failure,and the resistivity method used in monitoring the overburden failure is practical in principle.