Analysis On Roof Structure's Stability Of Longwall Mining In Shallow Seam

The Shenfu Dongsheng mining area is our country proven reserves biggest coal field the present, buries shallowly, on the duplicate thick loose sand bed is the mining area coal bed typical characteristic. Coal mining area in recent dip, storage stability, and the conditions for exploitation is predominant. But practice in the mine early mining shows that, coal mines buried in shallow not necessarily appear to ease pressure: longwall mining subsidence face widespread phenomenon roof height, and with Blown Sand and Water hazards such as a serious impact on the safety of mining output and efficiency.But the stope Blown Sand and Water disasters such as roof key question is, in fact, broken layer morphology and stability. The core question of The roof control is the control in the roof key stratum, on the research of the stability of the key stratum of the shallow coal seam roof stability is of great significance. This paper focus on the research of the course of primary tension and stability of the roof key stratum of shallow seam. Presses the appearance on the spot through the actual method study the basic rule of tension appearance the of the shallow seam; constitute the plastic three-pinned arch system's mechanical model After the roof key stratum's primary break, carries on the analysis to its stress situation and the movement situation, and forecast the disaster form which the roof possibly appears during the shallow seam's primary tension; Applying the initial flexure theory and unifies the shallow seam's bed characteristic, determined the limit submersion quantity of the roof after primary break and the horizontal thrust between the rock under the non-equilibrium state,gives the distinction basis of the roof's stair submersion, estimates the stair submersion quantity, estimates the stair submersion quantity,and picks the 1203 syntheses working surface of daliuta to perform the checking calculation as the project example; Picks the 1203 syntheses working surface of daliuta as the prototype development physical similarity modelling experiment, research the structure shape of the roof's primary breaking and the distribution rule of through crack and carries on the analysis to the experimental error.Finally, summarize the full text and put reasonable proposal of the direction of future research.