【摘要】 在工作面高抽巷中布置电法监测系统,所有电极均布置在巷道底板位置,采用并行电法仪采集数据,进行高分辨地电阻法反演成像,根据工作面回采与电性参数变化关系,分析了"垮落带"岩层的动态变化特征:伴随回采工作面的推进,存在采动应力影响,观测范围局部岩层裂隙发育,导致周期性的电性变化,可能与工作面周期来压事件有关;工作面周期来压期间,覆岩破坏可能以大块破断与冒落为主,电性参数变化大;工作面周期来压间隔期内,覆岩破坏可能以小块破断与冒落为主,电性参数呈渐变形式;给出了工作面超前采动应力作用范围、周期来压步距及垮落带高度。更多还原

【Abstract】 The observation system of electrical method was laid in the gas drainage tunnel above the coal face,with all the electrodes set in the tunnel floor.The electrical data were collected by the parallel electrical instrument,and the resistivity inversion of high-resolution ground electric resistance method was adopted to acquire the measured images.Based on the relationship between the electrical character variation and coal face caving locations,the dynamic variation features of caving zone strata were analyzed as follows:accompanying to coal face mining,there exists mining-induced stress in some locations of overburden strata,which lead to periodic electric character variation related to cycle weighting;during cycle weighting,the main form of overburden failures is large block of fracturing and collapsing,and the electric character features change greatly;during the interval of cycle weighting,the main form of overburden failures is small block of fracturing and falling,and the electric character features vary gradully;the results also yield the advanced range of mining-induced stress,the cycle weighting interval and the height of caving zone for the surveyed coal face.更多还原