【摘要】 为确定浅埋深煤层房柱式开采转长壁开采时区段煤柱的形式和稳定性,采用理论计算的方法,分析了已有房柱式开采区域内复采时区段煤柱的类型、受力特征及稳定性,提出了煤柱受力模型,并给出了不充填两柱一巷式、不充填三柱两巷式、充填两柱一巷式、充填三柱两巷式等4种煤柱的有效支撑宽度计算公式。以鄂尔多斯弓家塔煤矿为研究对象,计算了4种区段煤柱的失稳系数。结果表明:不充填型和充填型两柱一巷式、不充填型三柱二巷式区段煤柱失稳系数大于或接近1,存在失稳的危险性,充填型三柱二巷式区段煤柱失稳系数为0.64~0.87,可以保证长壁工作面开采时的区段煤柱的稳定性,满足了安全生产需要,最大限度地提高煤炭采出率。更多还原

【Abstract】 In order to determine the type and stability of the district sublevel pillars in shallow coal seam when converting room-and-pillar mining into longwall mining,the theoretical calculation method was adopted to analyze the type,mechanical characteristics and stability of the segment pillars during repeated mining in the room-and-pillar mining area and the mechanical model of the pillar was established,and effective bearing width calculation formulas of four different types of segment pillar were presented: two-pillar-and-one-roadway without backfilling,three-pillar-and-two-roadway without backfilling,two-pillar-and-one-roadway with backfilling,and three-pillar-and tworoadway with backfilling. Taking Gongjiata Coal Mine in Erdos area as the research object,the instability coefficient of the four kinds of segment pillars were obtained. The results indicated that the instability coefficient of two-pillar-and-one-roadway segment pillars with and without backfilling and three-pillar-and-two-roadway segment pillars without backfilling was greater than or near 1,which meant instability risk. The results also showed that the instability coefficient of the three-pillar-and-two-roadway segment pillars was 0. 64 ~ 0. 87. It could ensure pillars were stable during longwall mining,which could meet the requirements of mining safety and maximize the coal production.更多还原