刀把式工作面切眼对接阶段煤体采动应力分布规律研究

Research on mining stress distribution law of coal body during open-off cut butt-joining stage of knife handle working face

以云盖山二矿23304工作面为工程背景,对工作面基本顶的破断形式直接影响刀把式工作面由短工作面过渡到长工作面时切眼对接阶段衔接面周围煤体的应力分布和矿压规律进行了研究。采用理论分析结合3DEC数值模拟的方法分析了云盖山二矿23304刀把式工作面1号切眼工作面与2号切眼对接阶段基本顶不同破断形式和覆岩结构特征,揭示了不同岩梁属性对内应力场范围的影响规律。结果表明,侧向关键块B断裂位置对煤体影响程度由小到大依次为:采空区侧、煤壁前方、煤壁正上方,侧向基本顶断裂位置深入煤体6.21 m,内应力场范围约为12.91~14.43 m,煤体弹性模量对内应力场范围表现为负相关且影响最显著。

Taking the 23304 knife handle working face of Yungaishan No.2 Coal Mine as the engineering background,the pressure distribution and ground pressure law of the coal around the joint face during the transition from short working face to long working face are studied when the fracture types of the main roof of the working face directly affects the knife handle working face.Theoretical analysis combined with 3DEC numerical simulation was used to analyze the different fracture types and overlying rock structural characteristics of the main roof at the docking stage between No.1 open-off cut and No.2 open-off cut of Yungaishan No.2 Coal Mine,revealing the influence law of different rock beam properties on the range of internal stress field.The results show that the degree of influence of lateral key block B fracture on the coal body is from small to large:the side of the mining area,in front of the coal wall,and directly above the coal wall,the location of the lateral basic top fracture is 6.21 m deep into the coal body,and the internal stress field range is about 12.91-14.43 m.The elastic modulus of the coal body shows a negative correlation and the most significant influence on the internal stress field range.