关键词: 浅埋煤层, 高强度开采, 覆岩运动, 关键层, 钻孔

Abstract: In order to explore the overburden failure height of shallow-buried high-strength fully-mechanized mining face in 12407 working face of Huangyuchuan Coal Mine, two ground boreholes before and after mining were set up at the appropriate position above the working face. Based on the borehole data, the key strata and failure height of the overburden rock were theoretically analyzed and measured in situ, and the failure height of the overburden rock was determined by considering the multi-index factors. Through on-site measurement methods such as drilling flushing fluid consumption and downhole TV imaging, the change process of characteristic parameters in the process of pre-mining and post-mining drilling was monitored, and the multi-index comprehensive evaluation of overburden failure height was carried out. The results show that there are two key strata in the overlying strata of 12407 working face, and the fine-grained sand-stone at the buried depth of 88.7m-116.5m is the main key stratum of overlying strata. The development height of the water-conducting fracture zone of the overburden rock in the 12407 working face is about 77 m from the coal seam floor, which is close to the position of the main key stratum of the overburden rock, and the main key stratum has an inhibitory effect on the failure height of the overburden rock. Based on the comprehensive analysis of multiple indexes of overburden failure height, it can be seen that under the superposition of special conditions such as shallow burial, high-intensity mining and thick and hard bed-rock, the applicability of the empirical formula of ' two zones ' to calculate the height of fracture zone in this working face is general, and the development height of water-conducting fracture zone in 12407 work-ing face is comprehensively determined to be 77 m based on the measured value.