关键词: 关键词：近距离煤层组, 安全煤（岩）柱, 开采上限

Abstract: Abstract: In order to rationally develope the coal resources, maximize the utilization of water under the coal resources and mine sluggish coal resources, this paper took Yaoqiao mining 7 8 short distance coal seams group as an example. Using geological exploration, laboratory testing, theoretical analysis and other methods to analysis the nature of the impermeable layer of the Quaternary loose the lower layer,in order to determine the type of safety of coal (rock) pillar .On this basis, it is investigated the safety of coal (rock) pillar size and determined the upper limit of mining of 7 8 coal.The results show that: the unconsolidated layers lower stratosphere and the bottom of the aquifer as a weak rich water or aquifer to unconsolidated layers good impermeable layer at the bottom of the clay, so the safety coal (rock) column can be let as sand safety of coal (rock) pillar; The fully-mechanized mining upper limit of 7 coal is -157m in mining district; the whole thickness of stratified mechanized mining upper limit is -136m; thickness mining 2.5m mining upper limit is -129m; The fully-mechanized mining upper limit of 8 coal is 170m in 7 8 coal distance smaller regional, the other 7,8 coal distance larger area, whole thickness mining upper limit is -139m, thickness 2.5m mining upper limit is -135m.

Key words: Key words：short distance coal seams group, safety of coal (rock) pillar, upper limit of mining