Ming Xin Steep Coal Seam Of No.2Vertical Horizontal Section Of Roof Control Method Research Of Full-mechanized Caving Mining Face

Xinjiang mingschin coal company no.2shaft BaLiKun hami prefecture, xinjiang kazakautonomous county east stone coalpit coalfield in northwest, Merged layer of a layered for C2+3coal seam, the thickness of11.7~8.5m, an average of8.7m, the layers of C4+6coalseam, the average thickness of12m, from west to east gradually thinning. C3and C4seamspacing from west to east2~4.5m, a gradual increase in the average thickness of2.6m, dipAngle of coal seam58°~72°.Due to large dip Angle of coal seam, roof strata lithology is relatively hard, Thereforegenerally just after mining face is local of immediate roof and the false roof with mining withfall, And caving height is very limited, the caving rock mass is difficult to effectively isolatesthis section assignments on space and segmented goaf, May also induce upper old goaf in awide range of sudden collapse, thus making the segmented face is vulnerable to the impact ofthe upper goaf widespread suddenly caving rock mass stress, may face mine pressure appearphenomenon appears to be very sharp. And face above there are a large number of thewarehouse or lane pillar mining method to form a large number of old goaf, these mined-outarea could be accumulated a lot of poisonous and harmful gas and water, when the lower partof the working face in the process of mining may cause these old goaf large-scale caving ofroof and floor strata and movement, may be part of the mined-out area toxic or harmful gasesand water pressure in working face and cause serious disasters.Mingschin paper to xinjiang coal company no.2shaft as the background, take the siteinvestigation, the integrated use of rock mechanics experiment, similar material simulationand computer numerical simulation method, master the steep coal seam of no.2verticalhorizontal section of fully-mechanized caving roof movement form and motion law, provide a solid basis for roof control plans and measures.Research shows that: artificial explosions forced caving, must be conducted to ensureenough working face at the top of the effective isolation belt, can guarantee the safety inproduction.