关键词: 切顶成巷, 厚煤层, 数值模拟, 覆岩运动规律, 应力分布

Abstract: To explore the impact of top-cutting and roadway excavation technology in thick coal seams on the stability of the overlying strata，and to address the problems caused by the use of wide coal pillars in traditional mining methods，such as resource waste，stress concentration，and high support costs，the study was based on the 3105 thick coal seam working face of the Huoerxinhe Coal Mine as the engineering background. Using the FLAC3D numerical simulation software，a 3D model considering the ac⁃ tual geological conditions was constructed. The movement laws of the overlying strata in the mined-out ar⁃ ea，the subsidence amount of the roof，and the stress distribution characteristics of the surrounding rock under two working conditions (cutting the top and not cutting the top) were compared and analyzed. The re⁃ search results show that after implementing the top-cutting，the subsidence amount of the roof on the side of the roadway increased significantly by 101.28%，reaching 3.14 m. This effectively promoted the roof col⁃ lapse and utilized the fragmented coal and rock to fill the mined-out area. At the same time，the peak val⁃ ues of the advance support pressure and lateral support pressure，as well as their influence ranges，were significantly reduced. The vertical stress at the solid coal support of the roadway decreased from 23.18 MPa to 9.72 MPa，and the peak value of the shear stress decreased to 21.72%. This significantly improved the stress concentration state of the surrounding rock of the roadway. Based on the simulation results，specific cutting parameters (including cutting seam depth，angle，and explosive structure) for this thick coal seam and the corresponding constant resistance large deformation anchor cable and temporary support scheme were proposed and successfully applied in the field. The on-site monitoring data showed that the retention effect was good，the roadway cross-section was flat，the support working resistance remained at a low level (5.9 MPa)，and fully verified the effectiveness of this technology in controlling the deformation of the sur⁃ rounding rock and ensuring the stability of the retained roadway in thick coal seams by actively reducing pressure.

Key words: top-cutting and roadway excavation, thick coal seam, numerical simulation, overlying strate movement behavior, stress distribution