摘要
针对马道头煤矿8208坚硬顶板孤岛工作面回采巷道特殊的煤岩赋存条件,利用理论分析、数值模拟、工程设计等方法对小煤柱沿空掘巷采动应力分布及覆岩结构特征等进行了研究,分析了巷道侧向支承压力分布的计算公式,在此基础上使用控制变量分析法,研究了不同侧压系数、不同煤厚条件下支承压力的分布规律,得到8208工作面平均应力降低区范围为6~9.13 m,距离采空区边缘200 m之后基本处于原岩应力水平,侧向支承压力峰值处于距离采空区约20 m位置,采场上方由于坚硬K_(3)粗砂岩的存在,其破断后易于在巷道靠采空区侧形成悬臂梁结构,确定工作面右侧的辅运顺槽采用留设5 m小煤柱进行沿空掘巷。设计了8208工作面辅运顺槽顶板采用锚网索+组合锚索加强支护,两帮采用非对称支护形式,具体为采煤帮采用锚杆+短锚索间隔交替加强支护;煤柱帮采用锚杆支护。
Aiming at 8208 head hard roof coal and rock island mining face in Madaotou coal mine roadway special occurrence conditions, use of theoretical analysis, numerical simulation and engineering design method of roadway driving along goaf of small coal pillar mining stress distribution and the features of strata structure was studied, calculation formula of lateral abutment pressure distribution of roadway are analyzed, based on the applicable control variable analysis. Different lateral pressure coefficient is studied, and the distribution law of abutment pressure under the conditions of different coal seam, the stress reduced by an average of 8208 face zone from 6 m to 9.13 m, 200 m goaf edge after basic at the original rock stress levels, lateral abutment pressure peak value in the mined-out area about 20 m distance position, stope above as a result of the existence of hard K_(3) grit, After breaking, it is easy to form cantilever beam structure in the side of the roadway near the goaf, and 5 m small coal pillars are reserved for the auxiliary transport passage on the right side of the working face to carry out goaf excavation. The roof of the auxiliary transport passage of 8208 working face is strengthened with anchor mesh cable+combined anchor cable, and the two sides are supported with asymmetric support.Specifically, the coal side is strengthened with anchor rod+short anchor cable interval alternately. The pillar side is supported by bolt.
作者
赵杰
ZHAO Jie(Jinneng Holding Group,Datong 037000,China)
出处
《煤炭技术》
CAS
北大核心
2022年第12期71-75,共5页
Coal Technology
关键词
坚硬顶板
沿空掘巷
煤柱
数值模拟
hard roof
gob-side entry driving
coal pillar
numerical simulation
