陕北某矿双煤层开采对覆岩影响的模拟对比

Overburden failure simulation under double coal seams mining in a coal mine in north Shaanxi Province

多煤层开采条件下煤层覆岩破坏具有独特的特征,影响矿井生产布置。以陕北某矿为例,以该矿地质采矿条件为基础,采用相似材料模拟实验与数值模拟相结合的方法,通过建立模拟模型,开展了双煤层开采对覆岩的破坏影响研究。结果显示:留设不同宽度的煤柱,采用相似材料模拟和数值模拟2种方法得到的煤层覆岩垮落带高度、裂隙带高度都基本一致;在双煤层开采时,留设的煤柱宽度越大,两个煤层的叠置区域就越小,煤层开采对覆岩的破坏程度就越小。在工作面布置时,建议增大两个煤层的开采距离,并尽量增加煤柱宽度,以减缓覆岩移动破坏范围和破坏程度。研究成果为类似双煤层开采工作面的设计及覆岩破坏控制提供技术支撑。

Under the conditions of multi-seam mining,the overburden failure of coal seams has unique characteristics,which affects the mine production arrangement.Taking a mine in northern Shaanxi Province as an example,based on the geological and mining conditions of the mine,the influence of double-seam mining on overburden rock damage was analyzed by using the method of similar material simulation experiment and numerical simulation.The results show that the height of the caving zone and the height of the fractured zone in the overburden of coal seam obtained by using similar material simulation and numerical simulation with different widths of coal pillars were basically the same.In the double-seam mining,the larger the width of the coal pillar is,the smaller the superposition area of the two coal seams is,and the smaller the degree of damage to overburden is.In the arrangement of working face,it is suggested to increase the mining distance between two coal seams and increase the width of coal pillar as far as possible,so as to slow down the damage scope and the extent of overburden movement.