Reinforcing method for improving stability of gob-side entry driving small coal pillar

Abstract

The invention discloses a reinforcing method for improving the stability of a gob-side entry driving small coal pillar. The reinforcing method is characterized in that roadway-side pre-reinforcing anchor ropes are pre-arranged in an upper zone section stoping roadway close to a lower zone section lateral wall and located on the upper zone section wall of the small coal pillar before upper zone section working face stoping; multiple small coal pillar wall anchor rods and multiple small coal pillar wall portion reinforcing anchor ropes are arranged at the small coal pillar wall position in the lower zone section gob-side entry driving process, wherein the small coal pillar wall portion reinforcing anchor ropes include small coal pillar wall portion hollow grouting reinforcement anchor ropes and conventional reinforcement anchor ropes; small coal pillar wall concrete spraying layer is arranged on the small coal pillar wall when the lag distance of a gob-side entry driving head does not exceed 100 m; cement slurry reinforcement is performed on the hollow grouting reinforcement anchor ropes on the small coal pillar wall portion when the lag distance of the gob-side entry driving head does not exceed 200 m. The reinforcing method can prevent gob-side entry driving small coal pillar wall caving, improve the stability of the small coal pillar and reduce gob-side entry driving surrounding rock deformation amount.

Description

technical field [0001] The invention relates to a coal mine roadway surrounding rock reinforcement technology, in particular to a reinforcement method for improving the stability of a small coal pillar in a gob-side roadway under high ground pressure conditions. Background technique [0002] Goblining can be further divided into two forms: leaving small coal pillars and completely goblining. Full goaf entry refers to the arrangement of excavating the roadway along the edge of the goaf. At this time, the upper side of the roadway is loose and broken, and it is very easy to cause safety hazards such as gangue, air leakage, water penetration, and gas concentration in the upper gob. The scope of application is very limited. Gob-side excavation with small coal pillars is to reserve a certain width of coal pillars between the roadway and the goaf. Under high ground pressure conditions, the width of the coal pillars is generally 5-8m, so as to prevent water accumulation in the old...

AI Technical Summary

Problems solved by technology

However, after gob-side excavation, the loosening area of ​​the small coal pillar is large, and the anchor bolt is basically anchored within the loosening area. Failure, coal pillar slabs, resulting in a reduction in the effective width of small coal pillars and a reduction in the stability of coal pillars

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