Trinity coupling support stability control method for gob-side entry-driving coal pillar

Abstract

The invention provides a trinity coupling support stability control method for a gob-side entry-driving coal pillar, which is particularly suitable for a large-deformation gob-side roadway with an unstable overlying rock. A pre-stress threaded steel anchor rod is used on the gob-side entry-driving coal pillar on an upper zone roadway coal pillar side to tension a coal pillar goaf-side coal body; a short anchor rod on a lower zone gob-side entry-driving coal pillar side is used for controlling the integrity of a whole displacement region of a coal pillar roadway side; and meanwhile, a long grouting anchor cable is matched to reinforce an anchoring point so as to limit the development of an inner separation layer in the whole displacement region. A range of generating a crushed region of the coal pillar under the effect of lateral supporting pressure can be relieved under the expression of a haling effect of the pre-stress threaded steel anchor rod, so as to prevent an instability state of the coal pillar from worsening; and 'controlling by the short rod and grouting by the long rod' of the short anchor rod and the long grouting anchor cable are given into fully play so as to prevent a coal pillar support structure from losing effect and re-achieve the supporting capability of a remained anchoring structure in the coal pillar, so that coupling support with alternative anchor net support and anchor grouting support is formed between the gob-side entry-driving coal pillar side and a goaf side.

Description

technical field [0001] The invention relates to a coal pillar stability control method, in particular to a three-in-one coupling support control method for coal pillar stability in gob-side entry roadway with large deformation under unstable overlying strata in coal mines. Background technique [0002] The basis for the rapid development of gob entry technology is the surrounding rock control technology of gob entry, and maintaining the stability of narrow coal pillars is the key to the control of surrounding rock in gob entry. At present, the stability of narrow coal pillars in gob entry The research on control technology mostly focuses on the width of the coal pillar before digging and the support technology of the coal pillar after digging, etc., and has not fully considered the influence of the roadway support in the upper section, the excavation of the gob-side roadway, and the mining of this working face. During the process, the roadway surrounding rock control measure...

AI Technical Summary

Problems solved by technology

Under the condition that the overburden of the goaf in the upper section is not sufficiently stable, a stable residual bearing pressure has not been formed in the lateral coal body of the goaf, and the mine pressure is still unstable. The roadway generally has obvious deformation during the excavation period. When the working face is mined, affected by the advanced bearing pressure, the deformation and damage of the roadway are more serious, and even the side expansion is required to meet the production requirements, which will increase the production cost at the slightest and bring safety at the worst. Hidden danger

Images