为解决我国西南地区基岩裸露丘陵地区某河下煤层开采面临的安全问题,基于地质采矿条件,探讨上覆岩层破坏高度及防水安全煤岩柱尺寸留设情况,结合地表移动和变形预计,分析了煤层开采后河床所受的采动影响,并提出相应的采煤安全技术措施。结果表明:从导水裂缝带顶端至河床基底间的岩柱厚均大于340 m,导水裂缝带远未波及到河床基底;煤层开采后河床最大水平拉伸变形1.75 mm/m,最大倾斜变形5.0 mm/m,河床移动变形值较小,不会影响矿井安全开采。

In order to study on safety problem of seam mining under river in the hilly area with base rock exposed in Southwest China, based on the geological mini ng conditions, the paper discussed a failure height of the overburden strata and the size of the water prevention safety coal and rock pillars .And in combination with the surface movement and the deformation parameter prediction, the paper analyzed the mining operation affected to the river bed after the mining of the seam and provide d the relevant safety mining technical measures.The results showed that there was a rock pillar with a thickness over 340 m between the max elevation of the water flo W crack zone and the river bed base and the water flow crack zone was far from to the river bed base.After the seam mining, a max horizontal tensile deformation of the river bed was 1.75 mm/m, a max inclined deformation was 5.0 mm/m, a moving deformation value of the river bed was small and would not affect the safety of coal mini ng.