Strata Behavior Regularity Of Down Mining Face From Down To Up Of Shallow Close Distance Seam Groups In Daliuta Coa Mine

With the development of ShenDong coalfield,our scholars have thoroughly studied the shallow-buried coal seam under thin bedrock,found movement rules of overburden strata for typical shallow coal seam face of mining from down to up and strata pressure laws,which is a good guide on production.But researsh on strata behavior regularity of mining face from dow- n to up of Shallow close distance seams of ShenDong coalfield is less.It is necessary to carry out in-depth key research and this can provide theory and practice reference for shallow close distance seams safety mining.In this article,for geological conditions of Daliuta Huojitu well 12303 face,12304 face, 12305 face and12306 face, strata behavior regularity of the shallow coal mine whose closed distance is less than 15 miles was studied through mine pressure observation.And this article analysised the effect of trend and tendency coal to strata behavior regularity,the effect of dif- ferent landform to strata behavior regularity,and different closed distance to strata behavior regularity.The Study showed that strata behavior regularity of Daliuta Huojitul well 1-2 mining face was significant, support working resistance was larger during the periodic weighting, the periodic weighting presented non-uniform periodic change, the pressure step distance reduced with closed distance decrease, there were no significant differences during weighting and non- weighting, the regularity of the periodic weighting is not obvious, support working resistance changed little during the periodic weighting and dynamic load coefficient reduced. Dynamic load phenomenon often occurred on flow uphill position and flat-roofed position,because of critical layer breakage, Ditch slope movement,and the geological condition of HuojItu well which included Shallow buried depth, thin bedrock and huge unconsolidated soil layer. Study on effects of interlaminar space changes to mine pressure control has important implications to mining of Shallow Close Distance Seams in Bulianta coal mine,Halagou coal mine,Yujialiang coal mine and Shiqitai coal mine.