A successful case study on the reuse of gob side entry retaining by non-coal pillar mining in Gaohe mine

摘要

Based on the engineering background of gob side entry retaining in W1319 working face of Gaohe mine of Lu'an Group, this paper adopts the methods of field investigation, theoretical analysis and physical experiment to tackle the key technical problems of surrounding rock stability control during the effect of secondary mining and successfully retain roadway on site. The main research results are as follows: Firstly, the deformation and failure characteristics of surrounding rock of WIS 19 intake entry are investigated, the main factors affecting the stability of surrounding rock of gob-side entry retaining are determined, the key points to control the stability of surrounding rock of the gob-side entry are obtained, and the stability of top coal, coal wall and shoulder coal is determined as the starting point to control the stability of surrounding rock. Secondly, according to the stress distribution law of W1319 intake entry and the deformation and failure characteristics of surrounding rock, the reinforcement scheme of "high strength grouting + reinforcement anchor cable" combined support before secondary mining is put forward, and the concrete support parameters are obtained by theoretical analysis combined with site conditions. Industrial experiment and field mine pressure monitoring data show that the reinforcement support technology proposed can effectively control the deformation of surrounding rock, and verify the correctness of the reinforcement scheme proposed in this paper. As the first successful case of gob-side entry retaining reuse in non-pillar mining of Gaohe mine, it has a popularization significance.