坚硬顶板工作面切顶卸压参数合理性研究

Rationality of Roof Cutting and Pressure Relief Parameters in Hard Roof Working Faces

为研究坚硬顶板工作面切顶卸压参数的合理性,以姜家湾矿11#煤层工作面生产地质条件为研究对象,采用理论与数值模拟分析方法,给出并优化了切顶参数。研究结果为:基于工程条件,通过理论分析,得出切顶高度为11.4 m,切顶角度为1°~9°;结合理论计算,数值模拟得出在切顶角度为10°时的切顶卸压效果最佳;工作面切顶后,工作面顶板的位移相较于未切顶时的位移更大,该状态下的切顶效果较平稳,切顶后工作面应力下降了约20%,此时工作面应力集中范围扩大,并向深处延伸,采空区顶板对工作面挤压作用减小;进行了工程试验,布置了观测站,发现切顶后的顶底板移近量下降了约27%,锚杆受力下降了约24%,切顶后的围岩应力集中现象缓解。

In order to study the rationality of the roof cutting and pressure relief parameters in the hard roof working face,the production geological conditions of the 11#coal seam working face in Jiangjiawan Coal Mine were taken as the research object.Theoretical and numerical simulation analysis methods were used to provide and optimize the roof cutting parameters.The research results were as follows:based on engineering conditions and theoretical analysis,the cutting height was 11.4 m and the cutting angle was 1°-9°;combining theoretical calculations,it was found that the optimal pressure relief effect was achieved at a top cutting angle of 10°through numerical simulations;after roof cutting of the working face,the displacement of the face roof was larger than the displacement when the roof was not cut,the roof cutting effect in this state is relatively stable,and the stress of the working face after roof cutting decreased by about 20%,the stress concentration range of the working face expanded and extended deeper,and the squeezing effect of the goaf roof on the working face decreased;engineering experiments were conducted and observation stations were set up,which was found that the roof to floor convergence after cutting decreased by about 27%,and the force on the anchor rods decreased by about 24%,which meant that the phenomenon of stress concentration in the surrounding rock after top cutting was alleviated.