根据龙王沟矿煤层赋存条件及上覆岩层力学性质,研究近距离煤层上覆6上煤层已采对下覆6煤特厚煤层综放开采时支承压力的影响,进行了物理相似模拟实验研究。从围岩应力场分布角度对上覆已采煤层对下覆煤层综放面作用机理进行了分析。研究认为:该条件的近距离采空区下特厚煤层综放面在开采过程中,强矿压发生频率高,发生第二次周期来压后,每次周期来压发生时支架工作阻力超过模拟支架量程,达到24000kN以上,最大82952kN,对工作面危害大,支架上方顶煤破坏严重,煤壁片帮严重,支架超载、压架现象频繁,严重影响工作面的正常生产,所以采用垮落式采煤方法开采6上煤之后在采空区下一次开采21m厚的6煤,研究认为目前不可行。
According to the coal seam conditions and the overlying strata mechanical properties of Longwanggou Coal Mine, to research the impact of working resistance at the process of caving the extra 6 thick seam face under the condition of overlying 6 seam with close distance had been caved, the physical simulation experiment was carried out. Studies suggest that, under the given conditions, the strong mine pressure behavior occurs at high frequencies in the fully mechanized top coal caving in extremely thick seam under close distance goal, the working resistance exceeds the simulated bracket range to 24000 ~82952kN at each periodic weighting after the second, which can cause great damage to the working face, with severe top coal failure, rib spalling, frequent overloading and crushing of support, and impacts the regular coal production. The research suggests that, it is infeasible to apply full thickness (21m) mining in No. 6 coal seam under the goaf of No. 6upper coal seam mined with caving method.