Asymmetric bolt-mesh-cable combination support method for special-shaped mining roadway in large dip angle coal seam

Abstract

The invention discloses an asymmetrical bolt-net-cable combined supporting method for a special-shaped recovery tunnel of a large inclination angle coal bed. The method is characterized by comprising the following steps of: digging the tunnel according to the shape of the tunnel section, and supporting tunnel top plates, tunnel high-cut surrounding rock and tunnel low-cut surrounding rock by using prestressed anchor rods, steel bar nets and steel strips; arranging top plate prestressed anchor cables on the tunnel top plates; for the solid coal recovery tunnel, arranging high-cut prestressed anchor cables on the tunnel high-cut surrounding rock when the tunnel is dug for 5 to 7 days, and arranging struts in the center of the tunnel towards one side of the low-cut surrounding rock; and for the small coal post reserved recovery tunnel, arranging low-cut prestressed anchor cables on the tunnel low-cut surrounding rock when the tunnel is dug for 5 to 7 days, and arranging struts in the center of the tunnel towards one side of the low-cut surrounding rock. The combined asymmetrical supporting method has good application effect of stability control of the special-shaped recovery tunnel of the large inclination angle coal bed, the repair frequency of the tunnel is greatly reduced, and the supporting cost of the tunnel is reduced.

Description

technical field [0001] The present invention relates to a support method for a special-shaped coal seam recovery roadway with a coal seam inclination angle of 25° to 45°, more specifically, it is a support method suitable for an asymmetric structure coal seam mining roadway with large deformation of surrounding rock and serious bulging Support method. Background technique [0002] Coal seams with a large dip angle of 25° to 45° have a certain amount of occurrence in the world, and are mainly distributed in more than 20 countries including Urumqi, Beijing, Huainan, Kailuan, Xuzhou, Changguang, Nantong, Zixing, and Datong in China. mining areas, accounting for more than 14% of the mineable coal seams. [0003] At present, most mining roadways in large-inclination coal seams are supported by U-shaped steel retractable supports or I-shaped steel supports. It seriously threatens the safe and normal production of mines and restricts the development of safe and efficient producti...

AI Technical Summary

Problems solved by technology

However, due to the lack of in-depth research on the structural characteristics of the roadway surrounding rock, the stress load transfer characteristics of the roadway surrounding rock, and the mine pressure characteristics of the roadway with a coal seam dip angle of 25°-45°, especially for the roadway roof, high side of the roadway and low roadway The mechanical characteristics of the surrounding rock are not clear, and conventional bolt support is used, resulting in particularly serious deformation of the roadway surrounding rock, strong bulging of the side, difficult maintenance, and frequent repairs, high cost of roadway support, and difficulty in adapting to large-angle coal seam recovery The requirements for asymmetric deformation of the surrounding rock of the roadway cannot meet the requirements for safely controlling the stability of the surrounding rock of the roadway

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