浅埋大采高综放开采煤柱矿压显现规律研究

Study on Coal Pillar Pressure Behavior Law of Fully Mechanized High Cutting and Top Coal Caving Mining in Shallow Mining Depth

浅埋深大采高综放开采,因基岩厚度薄,工作面动载明显,区段煤柱宽度通常难以合理确定。通过在工作面区段煤柱内沿走向方向布置应力传感器,研究了煤柱受采动影响全过程的矿压显现规律。煤柱受工作面采动影响作用后,应力呈不对称的马鞍形分布,并且应力变化滞后于工作面的推进,靠近工作面采空区侧的应力集中系数要大于实体煤侧,2个马鞍形峰值间还存有8m左右宽度的低应力区,与离散元数值模拟结果相吻合,结果表明:煤柱内存在低应力弹性核区,经方案进行对比,确定合理煤柱宽度为20m。

Due to the base rock thin thickness and the dynamic loading obvious in the coal mining face,the width of the sectional coal pillars in the fully mechanized high cutting and top coal caving mining face in the shallow mining depth would be always hard to be rationally set up.With the stress sensors layout along the strike direction of the sectional pillars in the coal mining face,the paper studied the mine pressure behavior law of the coal pillars influenced by the mining full process.The coal pillars were affected by the mining operation of the coal mining face,the stress would be in an asymmetric saddle distribution and the stress variation would be beyond the advancing of the coal mining face.The stress concentration coefficient at the goaf side near the coal mining face would be higher than at the actual coal side.There was low stress zone with a width about 8 m between the two saddle type peak values which could fit the results of the dispersed element numerical simulation.The results showed that there would be a low stress zone in the coal pillar.In comparison with the plans,the rational width of the coal pillar was set as 20 m.