Abstract:
Aiming at the problems of low recovery rate of high-quality and scarce coal resources and poor stability of surrounding rock of goaf roadway, takes the No. 3 coal seam fully mechanized caving face of Jinxing Coal Industry as the research background, proposes the use of excavation along goaf with pre-built concrete wall technology, combined with theoretical analysis and numerical simulation methods, to study the stability of the surrounding rock and wall besides roadway of excavation along goaf with pre-built concrete wall under the influence of mining. The results show that the support scheme including the expansion and support of the original roadway, the construction of the wall beside the roadway and the roadway in the lower section is designed. According to the calculation, the safety factor and anti-sliding safety factor of the wall beside the roadway are greater than the standard value, and the wall design meets the safety requirements. Combined with the numerical calculation and analysis, the subsidence of the roadway roof in the working face mining process of 3101 transportation channeling and 3102 return air channeling is within the controllable range. Stress concentration occurs in the wall beside the roadway during the mining of two working faces, and the peak stress is 56.40% and 79.70% of the design strength of the wall, respectively. The deformation of the wall is less than 15 mm, and the surrounding rock of the roadway and the wall have good stability. Field monitoring show that after the research results are applied in the field, the deformation of roadway and wall is within the controllable range, and the application effect is remarkable. The research results provide reference for engineering applications under similar conditions.