A method for prevention and control of delamination water damage on the coal seam roof of a mine

Abstract

The present invention relates to the technical field of mine coal seam mining, in particular to a method for preventing and controlling water damage caused by layer separation on the coal seam roof of a mine. The height of the caving zone ensures that the mined-out area is fully filled. The roadway implements the two-way multi-stage "V"-shaped drilling method and blasting hole layout. The air tunnel and the machine tunnel on the working face simultaneously drill holes into the roof rock body and charge them. , blocking and detonation. The present invention can cause water-rich and thick hard roofs to be damaged and cracked at the blasting position by implementing advanced pre-splitting blasting, and can be further broken under the action of high ground stress, and can effectively solve the problem of roof water inrush and periodicity in fully mechanized caving mining working faces of water-rich roofs in coal mines. Problems such as irregular pressure; effectively prevent roof water and fault loads from being applied to the hydraulic support when the roof is out of water, so as to avoid the occurrence of press accidents.

Description

technical field [0001] The invention relates to the field of coal seam mining in mines, in particular to a method for preventing and controlling the water damage caused by separation of the roof of coal seams in mines. Background technique [0002] The prevention and control of mine water hazards has always been the focus of coal mine safety, and it is also an important factor restricting the safety of coal production. For fully mechanized caving mining of water-rich roof and extra-thick coal seam, when the thickness of the aquifer does not meet the safety distance, the fissure zone is easily connected to the aquifer. When the water is turned on, the working face is flooded. In severe cases, the working face is flooded, and the equipment cannot be withdrawn, resulting in significant economic losses. In addition to the dynamic load, the roof water loses the bearing effect of the rock layer, and its weight is also applied to the support, which is very prone to pressure acciden...

AI Technical Summary

Problems solved by technology

[0002] The prevention and control of mine water damage has always been the focus of coal mine safety, and it is also an important factor restricting coal safety production. For fully mechanized caving mining of extra-thick coal seams with rich water roofs, when the thickness of the water-resisting layer does not meet the safety distance, the fissure zone is easy to contact with the aquifer. When it is turned on, the working face will be flooded. In serious cases, the working face will be flooded, and the equipment cannot be withdrawn, causing major economic losses. According to relevant research, the water inrush from the roof of the working face is closely related to the incoming pressure. In addition to the dynamic load, the weight of the roof water is also applied to the support due to the loss of the bearing function of the rock formation, which is very prone to crushing accidents;

[0003] The thickness of the coal seam and the low strength of the overlying rock in the western region provide conditions for the occurrence of water-rich roof water damage. The prevention and control of water-rich thick hard roof water damage is the key to safe production in the western mining area. The main difficulties in mining are as follows: 1) The strength of soft rock is low, the surrounding rock is easy to be loose and broken, the deformation is serious, and it is easy to lose stability and cannot maintain the stability of surrounding rock for a long time; 2) The cementation of soft rock is poor, and the internal friction angle and viscosity of the rock mass The cohesive force is small, and the overall stability of the rock is poor; 3), the "soft rock" is easy to muddy, and it is a rock with low strength in a natural anhydrous state or dry condition. Once it encounters water, the rock will muddy and disintegrate , expansion, easily lead to deformation of the surrounding rock and even engineering accidents such as roof fall and landslides; due to the characteristics of cement in the northwest rock, drilling and drainage cannot be realized; the effect of using interval caving for top coal and interval caving is not obvious. During the mining process, the phenomenon of water pressure brackets appeared many times, and when the working face was harvested, the brackets almost fell apart;

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