Deep Buried Weak Bonding Of Thick Seam With Large Mining Height Fully Mechanized Working Face Of Study On Strata Behavior Regularity

To the west of a coal mine of the first mining faceas as background, The average thickness of the coal seam is5.4m, Working face burial depth of531～567m, Coal seam in deep buried depth。 The roof is clay、 calcareous cementation filling, Affected by various tectonic stress, The formation of fractured-porous media, By the strong denudation and osmosis loose aquifer in the upper formation deposition process, reduces the strength of rock, cause the roof rock strength low, The degree of cementation variation, Rock disintegration in water, for weak caking roof。 In this paper weakly caking roof condition, Use UDEC numerical simulation、analog simulation、 the theoretical analysis and so on, For deep and weak bonding of thick seam with large mining height fully mechanized mining field rock breaking and Working resistance of support is studied, Arrived at the conclusions:(1) Through the study of deep buried weak bonding thick seam mining overlying strata movement breaking process, First roof caving in the range of10～15m, the first weighting step distance is about20～25m, Periodic weighting step distance is about10～15m。 The height of caving zone as high as mining height4times。"Two belts" height is about22～24times higher。 Periodic weighting step distance is greater, Coal wall spalling prone。 When the working face advances to150m, The surface began to appear a slight sinking, With the continued advance, The maximum surface subsidence, The subsidence of about2.5m, And horizontal movement influence range is slightly larger than that of the length of working surface stoping。(2)Abutment pressure influence range is about in front of the coal wall5～35m。 When the working face first pressure, In front of the coal wall abutment pressure influence range is larger than that of periodic pressure period, normal development period; Different periodic weighting step distance of the abutment pressure influence range is different, Periodic weighting step distance is greater, and the larger the range of abutment pressure influence。In front of the coal wall abutment pressure peak at about10-15m away from the coal wall。 The initial pressure peak value of abutment pressure is greater than the periodic pressure period, normal development period, Different periodic weighting step distance of the peak value of abutment pressure are also different, Periodic weighting step distance is greater, Abutment pressure peak was higher in front of the coal wall。(3) Different mining height leads to working resistance of support、the working resistance of the supports is different during pessure during,and first breaking step is different。 With the increase of mining height, The first weighting step distance of working face is reduced; The average working resistance of support is enlargement, Support working resistance is greater when the pessure during. To improve the Support setting force, reduce the coal wall spalling phenomenon, reduce the roof subsidence。 With the increase of mining height, Coal wall spalling phenomenon is more severe。...