Study On Roof Structure And Rock Control Of Mountainous Shallow-Buried Close Multiple Coal Seams

Through the methods of pressure abservation similar material simulated numerical simulation and theoretical analysis the roof structure and rock control of mountainous shallow-buried close multiple coal seams were studied, pressure abservation results display that the pressure of the roof is big the rate of the valve opening is high and strata behavior is strong of the mountainous shallow-buried close multiple coal seams mining. Through the methods of similar material roof broken laws of mountainous shallow-buried close multiple coal seams, and in accordance with the difference of the roof broken the overing rock were divided in to two area. The two area are called "normal area of roof motion" and "unnormal area of roof motion". In the area of "unnormal area of roof motion" the roof broken trough the surface to the woking face and formed multilateral block sructure, and in the area of "normal area of roof motion" the roof formed stable three-band structure just like the normal buried coal seam mining. Though the stress analyes of the multilateral block sructure, the largest force location of the support happen when the support move to the border of the multilateral block sructure. Through the divided of the the two area and the stress analyes of the multilateral block sructure the phenomenon that the s strong strata behavior is well explained. Beside that the 3DEC numerical simulation method is used to study the the influnce of the angle of the hill and the mining direction. At last through the analyes of the Mechanical equilibrium condition of the multilateral block sructure reasonable support resistance of mountainous shallow-buried close multiple coal seams was confirmed. These results are very meaningful for the mining of mountainous shallow-buried close multiple coal seams.