根据相似模型试验,探讨了运用视电阻率法的物探技术来反演浅埋深覆岩采动裂隙发育演化规律的可行性,分析了采动过程中浅埋深煤层覆岩变形破坏前后电性参数的变化及其与覆岩裂隙发育范围、程度之间的关系。研究发现:视电阻率法可以探测浅埋深煤层覆岩采动裂隙的演化过程,电阻率变化率的等值线图可以体现裂隙发育形态,提出以电阻率变化率作为划分覆岩破坏"三带"的标准。在浅埋深煤层的采动过程中,上覆岩层导水裂缝带的范围持续向上方、前方扩展,但裂隙在水平与垂直方向的发育具有不平衡性,薄基岩层明显阻碍了裂隙向上的发育,水平方向的裂隙发育范围明显大于垂直方向。而一旦裂隙发育突破了基岩层,就会瞬间贯通该基岩层上方的附着岩层或地表。
On the basis of similar model test, the feasibility which mining-induced fractures evolution in overburden about shallow seam could be inversed by apparent resistivity method was discussed. The electric parameter changes in overlying strata during the course of deformation and failure and the relation between it and mining-induced fractures are canalized. The results show that apparent resistivity method can detect mining-induced fractures evolution in overlying strata about shallow seam. The isoline map of change rate in electrical resistivity could give expression to fracture development,so it can be the new division standard of the three failured strata zones. During mining active process in shallow seam,the range of fractured-zone in overlying strata is extended upward and forward, but it is imbalance in horizontal and vertical direction. The horizontal range is obviously larger than vertical, because the propagation of fractures is impeded by the thin bedrock. But once the thin bedrock is broken through by fractures, the upper rock or surface is instantly transfixion.