Research on movement and evolution law of breaking of overlying strata in shallow coal seam with a thin bedrock

Taking Yuyang coal mine as research base,this paper systematically has carried on experiments of the kinetic parameters of groundwater,the combined structure features of mechanics of overlying strata and the water-insulation character of weathered zone of bedrock.The result indicated: Water-bearing stratum at the bottom of eolian deposit sand strata is strong water-bearing stratum.The intensity of mudstone stronger than sandstone on the main production seam;the porosity,moisture content and tensile compression ratio of sandstone is great;the clay soil content of mudstone and sandstone is low.So it has new damage and excursion character of canonical brittleness,the feebleness capability of resist remolding and the feebleness revival capability of water-stop.It settled the character of dynamic vary of height in breaking of overlying strata in shallow coal seam with a thin bedrock as elements fitting based,and put forward long-wall mining to control blowing out Water and bursting sand.The technique apply in Yuyang colliery successful and put into green technical conservation water of mining.The paper settled foundation for further popularized apply high productive and high efficient mining and protect pysical environment for putting into green technical conservation water of mining for shallow coal seam with a thin bedrock in Yushen coal field in Northern Shaanxi.