厚煤层切顶卸压无煤柱自成巷围岩变形规律研究

Research on deformation law of surrounding rock in gob-side entry retaining by roof cutting and pressure release in thick coal seams

为研究厚煤层切顶卸压无煤柱自成巷道围岩变形规律,以柠条塔煤矿S1201-II工作面为工程背景,分别采用现场实测和FLAC3D数值模拟计算的方法对巷道顶底板变形及自成巷围岩支承压力分布进行研究。结果表明:厚煤层切顶卸压自成巷道围岩稳定性分布规律可分为压力变化区、压力趋稳区和压力稳定区三个阶段;在工作面向前推进期间,巷道围岩支承压力最大值达到9.19MPa,稳定值为8.47MPa,支承压力峰值点距离煤壁6~9m;确定滞后工作面200m为保守安全位置,200m后可全部回撤临时加强支护设备;滞后工作面90m之内巷道围岩变形明显,为重点支护区域,以确保生产安全。研究成果在现场实际工程中的成功应用,对于切顶卸压无煤柱自成巷道技术在厚煤层开采中的推广应用提供了有益借鉴。

In order to study the deformation law of the surrounding rock in gob-side entry retaining by roof cutting and pressure release in thick coal seams,in the engineering background of S1201-II seam face in Ningtiaota Mining,the deformation of the roof and floor in the roadway and the pressure distribution of the surrounding rock support were studied through field measuring and FLAC3 Dnumerical simulation. The results show that the distribution law of the stability of the surrounding rock in thick coal seam can be divided into three stages： pressure change zone,pressure stabilization zone and pressure stabilization zone. During the forward direction of working face,the rated value was 9. 19 MPa,the stability value was 8. 47 MPa,the supporting pressure peak point away from the coal wall is 6 ~ 9 m; the lagging working surface 200 m was identified as conservative safe location,after this position,all the temporary support equipment can be withdrawn. As for within lagging working surface 90 m surrounding rock deformation was obvious,this scope was the key support area to ensure production safety. The successful application of research results in the actual engineering of the site provides a useful reference for the popularization and application of gateway retained along goaf technology with roof breaking and pressure releasing in the thick coal seam.