【摘要】 应用PFC2D计算程序,对某矿水平与倾斜联合布置的折线型综采面,分析了散体顶煤和破碎直接顶的落放过程及落放形态,揭示了不同放煤步距连续推进模式下的煤损动态特征,并对不同放煤顺序的顶煤回收率及支架受力工况进行了优化分析.研究表明:折线型综采面采用自上而下的回采顺序,顶煤回收率高,支架受力均匀;低位单口放煤时,放出体形态向采空区侧偏转;在支架连续推进过程中,煤损形态节律性变化;大倾角厚煤层综放开采,采用中档放煤步距的经济技术效果较好.更多还原

【Abstract】 By using PFC~ 2D technique, the falling and moving process of top-coal and rock, and the flowing characteristics of loose medium in the process of top-coal caving in steep thick seam were analyzed for the horizontal and inclining compound working face arrangement of a coal mine by different recovering distances. The recovery of top-coal and the force characteristics of the powered supports for the top-coal caving working face by different caving sequences were discussed. The results showed that, firstly, the recovery of top-coal was high and the force characteristic of the powered supports for top-coal caving was good by adopting the top-to-down caving sequence. Secondly, the falling and moving configuration of loose medium was deflected toward the mined direction. Thirdly, the characteristic of lost coal in the process of top-coal caving was present with a particular rhythm. At last, the optimal caving distance was 1.2 m in all the conditions.更多还原