Non-blasting roof-cutting gob-side entry driving method for pier stud

Abstract

The invention discloses a non-blasting roof-cutting gob-side entry driving method for a pier stud. The method comprises the following steps of forming a plurality of joint-cutting holes which jointlyform a pre-cracking kerf, and drilling 60-100 m of a first advance of the joint-cutting holes; excavating an upper of a coal pillar on one side, close to the coal pillar, in a gateway close a next working face at every 5-10 m and arranging concrete pier stud dies; using a single hydraulic support pillar and n-type steel in the gateway as temporary support; carrying out anchor-retreating construction in the gateway next to the next working surface; recovering the single hydraulic support pillar following 2-5 m behind the working surface closely; and forming a pre-cracking joint-cutting caving on a top plate next to a gob-side entrydriving lane along the joint-cutting holes, eliminating a hanging arch, filling a gob, and carrying out gob-side entrydriving construction at 3-5 m coal pillar after recovery of adjacent gob. By adopting non-blasting roof-cutting pressure relieving for the pier stud, a gob-side entrydriving operation for a small coal pillar can be carried out on adjacent working surface, so that a mine excavation succeeding tension situation is alleviated greatly, the repair cost of the gob-side entry driving is reduced, and the coal recovery rate is improved.

Description

technical field [0001] The invention relates to a gob-side digging method for pier pillars without blasting and top-cutting, and belongs to the technical field of shallow geothermal energy. Background technique [0002] The traditional gob-side entry generally starts construction more than 10 months after the mining of the adjacent working face. The coal pillars are small, and the roadway of gob-side entry is in the stable zone of rear bearing pressure, so the maintenance of the roadway is relatively easy. Mining of coal seam groups at close distances has high in-situ stress, great influence of mining, and tight excavation succession. Often the adjacent working faces are excavated before the goaf is completely mined, and the sideways hanging area of ​​the goaf next to the coal pillar is prone to appear. large and insufficient caving, the roadway is significantly affected by the movement of the overlying rock in the adjacent goaf, and the mine pressure is severe. Under the in...

AI Technical Summary

Problems solved by technology

[0002] The traditional gob-side entry generally starts construction more than 10 months after the mining of the adjacent working face, the coal pillar is small, the roadway of gob-side entry is in the stable zone of back bearing pressure, and the roadway maintenance is relatively easy

Mining of coal seam groups at close distances has high in-situ stress, great influence of mining, and tight excavation succession. Often the adjacent working faces are excavated before the goaf is completely mined, and the sideways hanging area of ​​the goaf next to the coal pillar is prone to appear. large and insufficient caving, the roadway is significantly affected by the movement of the overlying rock in the adjacent goaf, and the mine pressure is severe. Under the influence of strong mining in this working face, the deformation of the roadway is large and the repairs are frequent, which seriously threatens the safe and efficient mining of the mine

[0003] Adopting heavy-duty U-shaped steel retractable brackets and reinforced control technology for post-filling of the combined frame supported by bolts, the supporting process is complicated and the cost is high

Increase the width of isolated coal pillars, resulting in low coal recovery rate, great waste of resources, and shortened mine service life

Therefore, neither of the above two main methods can satisfy the stability of the low-cost roadway and the normal replacement of the working face in the gob-side roadway under the high-stress and strong-dynamic-pressure soft rock.

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