关键词: 三软厚煤层, 大跨度巷道, 切顶卸压, 沿空留巷, 充填体宽度

Abstract: Abstract: Based on the engineering background of the large-span mining roadway in the three soft and thick coal seams of Zhaojiazhai Coal Mine, combined with the actual project after the road expansion, the plan of filling and retaining roadway in the pre-cut roof is proposed. Through theoretical analysis and numerical simulation method, the stress characteristics of surrounding rock in mining roadway under non-cutting and cutting conditions are compared and analyzed, and the remaining width of filling wall under cutting condition is determined to be 2.2m. The on-site monitoring results show that under the condition of pre-cutting top pressure relief, when the filling wall width is 2.2m, the stability of the mining roadway can be effectively maintained, and the roadway can be smoothly carried out. The research results can provide a reference for the retaining of the long-span mining roadway in the three-thick thick coal seam under similar conditions.