关键词: 大倾角煤层, 顶煤垮落, 煤岩分界, 放煤工艺

Abstract: In response to the complex top coal collapse morphology，unclear coal-rock boundary， and unstable coal release efficiency in the comprehensive mining face of the Pangpangta Mine with a steep coal seam，the 1029 working face was selected as the research object to conduct research on the optimiza ⁃ tion and application of the coal release process.By establishing a top coal release body morphology model and constructing the PFC2D numerical simulation platform，the top coal collapse behavior and coal-rock boundary characteristics under different coal seam thickness and inclination combinations were analyzed， revealing the coupling relationship between the release body structure evolution and recovery efficiency . Based on this，the influence of four coal release methods on the release effect was simulated and com ⁃ pared，and it was clearly identified that the "two-stage sequential descent"coal release method had a high ⁃ er top coal recovery rate and clearer boundary.Combined with on-site experiments for verification，after optimizing the coal release process，the top coal recovery rate increased from 82.3%to 89.7%，an increase of 7.4 percentage points.The stability of the supports was enhanced，and the utilization rate of the coal source and the cycle efficiency were also improved.

Key words: steep coal seam, top coal collapse, coal-rock boundary, coal release process