厚松散层软弱覆岩工作面“三带”发育特征与高度研究

Study on the development characteristics and height of“three zones”of the working face covered with thick alluvium and weak overburden

为探究厚松散层软弱覆岩地质条件下采动覆岩运移规律,基于葛泉煤矿11915工作面采矿地质条件,采用室内相似模拟方法,分析该工作面推进时的直接顶初次垮落、高位覆岩破坏动态过程,得出该工作面覆岩垮落带、断裂带与弯曲带(简称“三带”)高度范围;分析了采动覆岩“三带”内岩层位移特征,得出位于垮落带、断裂带与弯曲带内的岩层位移曲线呈波动性递减趋势。研究结果表明:11915工作面垮落带范围为10~25 m,断裂带高度范围为43~48 m,位于48 m之上的岩层属于弯曲带范围,相似模拟结果与现场实测结果相近,验证了相似模拟实验的合理性。

In order to study the migration law of subsidence overburden strata under the geological condition of thick alluvium and weak overburden,based on the mining geological conditions of 11915 working face in Gequan Coal Mine,this paper analyzed the dynamic process of the first caving of the immediate roof and the failure of high overburden when the working face was advancing through the indoor similar simulation method.The height range of overburden caving zone,fractured zone and bending subsidence zone(referred to as“three zones”)was obtained;the displacement characteristics of strata in the“three zones”of subsidence overburden were analyzed,it reflected that the strata displacement curves in caving zone,fractured zone and bending subsidence zone show decreasing fluctuation trend.The results show that the caving zone of 11915 working face ranges from 10 m to 25 m,the height of the fractured zone ranges from 43 m to 48 m,and rock strata above 48 m belongs to the bending subsidence zone.The similarity simulation results are close to the field measurement results,which verifies the rationality of the similarity simulation experiment.