Self-forming roadway mining method without coal pillars suitable for fully mechanized top coal caving in thick coal seams

Abstract

This application relates to the technical field of coal mining, and in particular to a coal-pillar-free self-forming roadway mining method suitable for fully mechanized top coal caving in thick coal seams, which includes the following steps: reinforcing and supporting the roof and two sides of the roadway; Roof slit blasting to form pre-splitting slits; temporary support devices and gangue blocking devices in the roadway are erected along the roadway retention; coal is not released within the preset distance near the end of the working face on the side of the roadway retention; after the roadway is stable, it is removed The temporary support device in the roadway, and the gob area is closed, and the roadway is left to complete. Roof slit blasting is more conducive to the collapse of the rock formation in the goaf, so that the rock formation in the slit can better fill the mining space after the rock formation collapses. The formation of a longer suspended roof improves the surrounding rock stress of the gob-side entry retaining; no coal is discharged within a certain range at the end of the working face on the side of the entry entry, which further ensures the filling effect of the side void area of ​​the entry entry and effectively limits the rotation of the basic top block The sinking greatly reduces the impact on the stability of the lane.

Description

technical field [0001] The application relates to the technical field of coal mining, in particular to a coal pillar-free self-forming roadway mining method suitable for fully mechanized top coal caving in thick coal seams. Background technique [0002] Coal is the main energy source in our country, and its reserves are abundant. Among my country's proven coal reserves, reserves in thick coal seams account for 44%, which is my country's resource advantage. The fully mechanized top-coal caving technology for thick coal seams has become an important development direction of my country's thick coal seam mining technology because of its safety, high efficiency and low cost. However, due to the large mining height of the thick coal seam, after the coal seam is mined, the goaf space is large, and the range of overlying rock activities on the roof of the stope caused by the large mining height increases, especially under the condition of a hard roof, it is easy to cause the overha...

AI Technical Summary

Problems solved by technology

[0004] However, the current self-forming roadway technology without coal pillars is mainly applied to coal seams with a thickness not greater than 4m. In recent years, with the development of technology, the self-formed roadway technology without coal pillars has gradually been applied to thick coal seams, but the above thick coal seams are all fully mechanized mining technology , there have never been relevant reports on the self-forming roadway technology without coal pillars under the condition of top-coal caving mining in thick coal seams

Under the condition of top-coal caving mining in thick coal seam, if the traditional method of gob-side entry retention in medium-thick coal seam is adopted, the length of the anchor cable for roadway roof support needs to be about 3 times the mining height, and the thickness of fully mechanized mining in thick coal seam is 8- More than 15m, the required anchor cable length reaches about 30m, which cannot be realized by the existing technology

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