Non-coal-pillar auto-roadway-forming mining method suitable for thick-seam fully mechanized top coal caving

Abstract

The invention relates to the technical field of coal mine mining, in particular to a non-coal-pillar auto-roadway-forming mining method suitable for thick-seam fully mechanized top coal caving. The method includes the following steps that reinforcing and supporting are carried out on a roof and two walls of a roadway; roof cutting explosion is carried out to form a pre-cracking seam; a temporary supporting device in the roadway and a gangue blocking device are erected along a retained entry; coal caving is not performed within a preset distance to the working face end close to the entry retaining side; after the roadway is stabilized, the temporary supporting device in the roadway is removed, a goaf is closed, and the entry retaining is completed. The roof cutting explosion better facilitates collapsing of the rock stratum in the goaf, the stoping space can be well filled after the rock stratum in the seam is collapsed, a short arm beam structure is formed in the lateral direction of the entry-retaining roof, a long suspended roof formed in the goaf is avoided, and the surrounding rock stress of the gob-side entry is improved; coal caving is not performed within a certain range ofthe working face end of the entry retaining side, the filling effect of the empty area of the entry retaining side is further guaranteed, rotary sinking of basic top block bodies is effectively limited, and the influence on the entry retaining stability is greatly reduced.

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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