基于楔形椎体模型工作面煤壁稳定性研究

Stability of Coal Walls in Working Face Based on Wedge-shaped Vertebral Model

针对大同矿区复杂地质条件工作面回采期间煤壁稳定性较差的问题,以大同矿区某煤矿1022工作面为工程背景,通过理论分析、数值模拟,对影响煤壁稳定性的因素进行了研究。结果表明:工作面采动期间,煤壁失稳片帮过程分为煤体损伤破坏阶段和煤壁剪切滑移失稳阶段。在煤体损伤破坏阶段,工作面前方煤体应力环境被恶化,加剧了应力畸变区煤岩体单元的损伤破坏,增大了煤壁片帮机率;在煤壁剪切滑移失稳阶段,根据楔形椎体力学模型,发现煤壁稳定性系数K随支架护帮力P0、结构面内聚力C和内摩擦角φ的增大而增大,随顶板压力的增大而减小,并据此提出了煤壁稳定性控制措施。

Aiming at the poor stability of coal walls during mining in complex geological conditions in the Datong mining area,the influencing factors of coal wall stability were studied through theoretical research and numerical simulation,taking No.1022 working face of one mine as the engineering background.The results show that during the mining,the coal wall spalling instability process could be divided into the coal body damage stage and the coal wall shear-slip instability stage.In the coal body damage stage,the stress environment of coal body in front of the working face deteriorated,which aggravated the damage of the coal rock unit in the stress distortion areas and increased the chance of coal wall spalling;in the coal wall shear-slip instability stage,according to the wedge-shaped vertebral mechanics model,it is found that the stability coefficient K increased with the increase of the support protective force P 0,structural surface cohesion C,and internal friction angleφ;it decreased with the increase of roof pressure.Based on this,we proposed some control measures for coal wall stability.