近距离煤层残留煤柱下回采巷道变形破坏研究

Research on deformation and failure of mining roadway under residual coal pillar in close distance coal seam

近距离煤层开采,上煤层残留的不规则煤柱引起的集中应力向下传递,造成下煤层回采巷道变形严重甚至垮落。以中国西部矿区某矿为例,根据现场观测数据,研究近距离煤层下煤层巷道受上煤层不规则残留煤柱影响下的矿压显现规律。结果表明,把辅助运输巷的破坏过程划分为3个阶段,前2个阶段区段煤柱承受的载荷逐渐增大到最大值,在第3个阶段区段煤柱处于残余强度阶段,煤柱支承能力下降导致变形严重,巷道上部顶板呈倾斜状。该结果可为其他类似地质条件下巷道支护提供借鉴和理论支撑。

In the mining of close coal seams,the concentrated stress caused by the residual irregular coal pillars in the upper coal seam is transmitted downward,causing serious deformation or even collapse of the mining roadway in the lower coal seam.Taking the close distance coal seam mining in a mine of western China as an example,based on the field observation data,the mine pressure behavior of the roadway in the lower coal seam under the influence of the irregular residual coal pillars in the upper coal seam is studied.The results show that the failure process of the auxiliary transportation roadway can be divided into three stages.In the first two stages,the load on the coal pillar gradually increases to the maximum value.In the third stage,the coal pillar is in the stage of residual strength,the support capacity of the coal pillar decreases,resulting in serious deformation,and the roadway roof is inclined.The results can provide reference and theoretical support for roadway support under other similar geological condition mines.