Overburden Movement Pattern Of Fully Mechanized Sublevel Caving Longwall Face 120210 Of Zaoquan Coal In Steep And Variable Inclined Seam

The fully mechanized caving working face120210 in Zaoquan coal mine is classified as steeply dipping seamface with variable angle.Affected by the variation of seam dip angle, strata movement and gangue filling was complex in fully mechanized caving workface in steeply dipping seam, resulting that it is difficult to achieve efficient production with conventional caving technology and difficult to achieve security management. In order to expand the mining technology in caving workface in steeply dipping seam, it has high theoretical and practical value in the research of the lawof overlying strata and top coal deformation, destruction and migration.Thesis combined with physical simulation experiment, numerical analysis and field monitoring methods to study the lawof overlying strata and top coal deformation, destruction and migration,the time distribution of apparent stress and strata behaviors incaving workface in steeply dipping seam, results show that:The movement of roof along the dipdirection of the working face is variableindifferentarea. In the upper region, the movement is similar with gently inclined seam, as the angle is tiny and caved rock keep in the place. In the lower region, the movement is similar with steeply dipping seam, caved rock slip along dip direction into and fill the gob. The middle region is the key transformed region, the migration characteristics is combined with gently inclined seam and steeply dipping seam.Selectivemovementofstrata result in selective distributionofabutment pressure in front of the coal wall. As seem angle change, the shape of the drawn-out body shift. And the key area is the transformed region betweenthe lower regionand the middle region, the middle region andthe upper region.Strata behaviors and stabilitycharacteristicofsupportin the fully mechanized caving working face120210 reflectedselectivemovementofstrata. The method of groundcontrol in steeply dipping seamwasputforward: the upper region isthemainbodyofhigh production and high efficiency, The lower region, is the basic of stability of working face, the key of high production and high efficiency.