Deep hole blasting and static water injecting combining coal seam weakening method

Abstract

The invention discloses a deep hole blasting and static water injecting combining coal seam weakening method which comprises the following steps: (1) arranging a plurality of groups of drill holes in the coal seam, wherein the drill holes in each group include a blasting hole and a control hole; (2) pushing hole protection pipes into the control holes one by one, and connecting the adjacent hole protection pipes by steel wires longitudinally in a winding way, wherein the diameter of each hole protection pipe is less than 10mm; (3) charging explosive cartridges into the hole protection pipes according to the linear loading density, pushing the hole protection pipes into the blasting holes one by one, sealing the blasting holes with yellow mud after loading is completed, and blasting; (4) injecting water into the blasting holes and the control holes at static pressure simultaneously through four seams of the hole protection pipes in the blasting holes and the control holes, and diffusing and permeating water into cracks generated by blasting to fully wet coal; and (5) recovering the hole protection pipes in the control holes after water injection is completed. After the drill holes are blasted, the drill holes can not collapse, and many cracks can be formed in the coal seam. In addition, because water can be injected into the coal seam through the blasting holes and the control holes, the strength of the coal seam can be reduced effectively.

Description

technical field [0001] The invention relates to a coal seam weakening method combining deep hole blasting and static pressure water injection, which belongs to the technical field of coal seam weakening. Background technique [0002] When mining a thick coal seam, if the coal seam is relatively hard or has high toughness, it is not easy to break and break during mining, and the mined coal block is large in size, which is not conducive to transportation and is not safe. In order to solve this problem, it is often necessary to weaken the coal body. Regarding the weakening of the coal seam, domestic and foreign coal scientific researchers have done a lot of research, including advanced deep hole pre-splitting blasting at the working face, high-pressure water injection pre-splitting, and static pressure water injection softening. Or coal seam weakening methods such as combining blasting and pre-splitting. [0003] The published papers are all specific applications of the above ...

AI Technical Summary

Problems solved by technology

[0005] The present invention provides a coal seam weakening method that combines deep hole blasting and static pressure water injection to solve the above-mentioned defects in the prior art, and solves problems such as easy collapse and blockage of the borehole and difficult static pressure water injection during deep hole blasting of the coal seam. A series of problems, the effect is obvious, and it has good practicability

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