采用现场实测、三维相似材料模拟、数值模拟和理论分析,对深井宽条带法开采煤柱稳定性及地表移动特征进行研究。研究表明:深井开采其煤柱塑性区的宽度明显增大,条带煤柱承载应力分布为明显马鞍形;煤柱横向变形主要集中在边缘9.5 m内,且呈现非连续、阶跃式、突变形态。随着煤柱留设宽度的变小,煤柱塑性区宽度显著增加,条带群开采地表下沉达到了该地质采矿条件的极值,下沉系数为0.22,下沉盆地面积大,但平缓且较均匀,移动变形连续且周期长,在下沉盆地外边缘出现了地表反弹轻微抬高的现象。针对深井宽条带法开采的特点,提出了深井宽条带法开采煤柱尺寸的计算设计方法。
Coal pillar stability and surface movement characteristics of wide strip pillar mining in deep mine have been researched by using field measurement, three-dimensional similar material simulation, numerical simulation and theoretical analysis. Researches show that under the mining conditions of deep mine, the width of plastic zone becomes larger significantly and load bearing above the whole coal pillar in deep mine is saddle-shaped;The lateral deformation is discontinuous, stepped and mutational, which is focused on the edge 9.5 m away from the coal wall. With the diminution of coal pillar’s width, the width of plastic zone increases notably. In addition, surface subsidence reaches extremum under this geological and mining condition in group strip coal pillar mining. The subsidence basin is larger but gentler and uniform. The subsidence coefficient is 0.22 and the movement and deformation is conti-nuous and long-term. Outer edge of subsidence basin appears surface rebound. Based on the characte-ristics of deep wide strip pillar mining, the dimensional design method has been put forward.