关键词:

特厚煤层 , 沿空巷道 , 底鼓机理 , 联合支护 , 围岩控制

Abstract: In order to solve the problem of asymmetric damage of the floor of the gob-side roadway under the influence of dynamic pressure due to tense mining relationship, on-site research, theoretical analysis, numerical simulation and on-site industrialized test is adopted to take the 5209 return roadway as the object of research, and the formula to calculate vertical stress on both sides of roadway during the roadway excavation period and after the upper face mining by the mechanical analysis is derived. The mechanism of asymmetric floor heave in roadway was elucidated through numerical simulation analysis. The results showed that the stress superposition caused by excavation and working face mining was manifested as the stress on the coal pillar side of the roadway being greater than that on the solid coal side, and the asymmetric distribution of stress caused asymmetric deformation of the roadway floor. The displacement curve of the roadway floor by numerical simulation during roadway excavation shows a symmetrical distribution, with a maximum displacement of 29mm. The deformation of the floor during upper working face mining is asymmetric. The displacement of the left floor of the roadway is maximum at a distance of 0.5m from the central axis, with a peak displacement of 593mm. The plastic zone of roadway gradually expands during the upper working face mining, the depth of the floor failure is 5.5m. According to the principle of collaborative control of roof, sides, and floor, the cooperative control scheme of "leveling floor + anchor cable support + concrete hardening" is proposed and successfully applied in the field practice.