综放面强动压区巷道变形破坏特征及锚索强化支护机理研究

Deformation characteristics and reinforcement support mechanism with anchor cables for roadway in strong dnamic pressure area of fully mechanized top-coal caving face

针对山西宁武榆树坡煤业有限公司5107综放工作面开采强度大、超前支护劳动强度高、动压区巷道变形严重等问题,监测分析综放工作面超前段巷道围岩变形破坏特征,建立了巷道顶板锚索支护力学结构模型,基于冒落拱理论与悬吊理论精准量化动压区回采巷道所需强化支护强度,建立数值模拟模型分析综放工作面超前支承压力分布规律,优化综放面强动压区回采巷道锚索强化支护参数并进行工业性试验。结果表明,综放工作面动压区回采巷道超前支护强度整体不足,巷道顶板起伏剧烈,侧帮严重鼓出,严重制约安全生产;结合冒落拱理论与悬吊理论分析了巷道厚煤层开采顶煤破坏冒落特征,精准量化了动压区回采巷道超前段所需强化支护强度为33.74 kN/m^(2);通过数值模拟确定了“3根全长锚固补强锚索”,最外侧锚索向外倾斜15°的补强支护方式可有效控制动压区回采巷道围岩变形;进行了现场工业性试验,试验表明5107工作面回风巷顶底板、左右帮变形分别为81、189、134、145 mm,锚索补强支护条件下回风巷超前段围岩平整规则、整体稳定性良好。

In response to the problems of high mining intensity,high labor intensity of advanced support,and severe deformation of roadway in the dynamic pressure area of 5107 fully mechanized top-coal caving face of Yushupo Coal Industry,the deformation characteristics of the surrounding rock of the roadway in the leading section of the fully mechanized caving face were monitored and analyzed,a mechanical structure model with anchor cable support of roadway roof was established,the required reinforcement support strength for the dynamic pressure area of the mining roadway was accurately quantified based on the theory of caving arch and suspension,a numerical simulation model was established to analyze the distribution law of advanced support pressure in fully mechanized caving face,and the anchor cable reinforcement support parameters for the mining roadway in the strong dynamic pressure area of the fully mechanized caving face were optimized and relevant industrial tests were conducted.The results showed that the overall strength of advanced support for the mining roadway in the dynamic pressure area of the fully mechanized caving face was insufficient,the roof of the roadway fluctuated violently,and the side walls bulged severely,which seriously restricted safety production.By combining the theory of caving arch and suspension,the characteristics of roof coal failure and caving in thick coal seam mining were analyzed,and the required reinforcement support strength for the leading section of the mining roadway in the dynamic pressure area was accurately quantified as 33.74 kN/m^(2).Through numerical simulation,it was determined that the reforcement and support modes with 3 full-length anchoring and reinforcement anchor cables and the outermost anchor cable tilting outward by 15°could effectively control the deformation of the surrounding rock of the mining roadway in the dynamic pressure area.Industrial tests had shown that the deformation of the roof,floor and both sides of return airway of the 5107 working face were 81 mm,189 mm,134 mm and 145 mm,respectively.Under the condition of anchor cable reinforcement support,the surrounding rock in the leading section of the return airway was flat and regular,and the overall stability was good.