【摘要】 在现场观测的基础上 ,采用非连续变形分析 (DDA) ,分别对初次来压前和周期来压前采场上覆岩层的变形、结构模式、形态与关键层等进行动态模拟 .结果表明 :DDA模拟显示了随着工作面的推进 ,上覆岩层变形、破裂、结构、运动的动态过程 ,模拟是可行的 ;初次来压前 ,上覆岩梁移动同步协调一致 ,且布置在梁中部咬合处下方的监测点 1和 2的垂直位移几乎相等 ,说明断裂岩梁在此处互相联锁咬合而取得平衡 ,从而形成了具有 3个咬合点的“三咬拱”结构 ;周期来压前 ,各监测点垂直方向的位移、速度、加速度特性曲线形状极为相似 ,表明断裂岩梁在移动下沉过程中 ,同步协调一致 ,仍然处于联锁咬合状态 ,且随着岩梁的下沉运动 ,位移与速度有趋于定值的趋势 ,说明岩梁形成了咬合岩梁结构 ;采场上覆岩层中的关键层在上覆岩层活动的某一阶段起主要承载作用更多还原

【Abstract】 Based on the site measured data, the discontinuous deformation analysis(DDA) is adopted to model respectively the structural patterns, forms, displacement and key stratum (dynamic modeling) in the overlying strata of longwall face before the first and periodic weighting, and the following conclusions are drawn out: (1) the dynamic modeling shows the whole process of deformation, rupture, structure and movement in the overlying strata while the coal face advances, and the modeling is feasible; (2) before the first weighting, movement of rock beams in the overlying strata is synchroneus, coordinate and accordant, and the vertical displacement at monitoring points 1 and 2 below grip face of beam center is nearly equal, which means that the rupture rock beams interlock each other and grip with, and balance, thus the three grip arch structure in the overlying strata is formed; (3) before the periodic weighting, the shapes of the behavior curves for the vertical displacement, velocity and acceleration are very similar, which means that the rupture rock beams still interlock each other and grip with, and balance in the movement process, and as the rock beams move, the displacement and the velocity tend to a constant, which shows that the grip beam structure in the overlying strata is formed; (4) the analysis shows that the key stratum plays a role of the main supporting stratum in the overlying strata movement.更多还原