煤焦共生煤层沿空巷道分阶强化支护技术

Technology of Reinforcement Supporting in Stages for Roadway Along Goaf in Coal Seam of Coal and Tar Symbiosis

为解决某矿煤焦共生煤层沿空巷道长期维护的难题,结合此类巷道围岩易片帮、完整性差、变形剧烈等特征,分析了巷道变形破坏机理,认为巷道围岩特性、顶板岩层赋存、邻近巷道影响、毗邻工作面回采等是造成该巷道难以维护的主要因素;提出了分阶强化支护的技术思路及以超前预注浆、喷层防片帮、高强锚杆支护、分阶支护等技术为主的煤焦共生煤层沿空巷道分阶高强支护体系。现场实践表明,巷道成巷100 d内,两帮移近量接近200 mm,顶板下沉量接近40 mm,巷道围岩整体趋于稳定。

To solve the problem that maintain the stability of the roadway along goal for a long time,the mechanism of roadway deforma- tion failure was analyzed,combined with characteristics of the roadway surrounding rock such as easy spalling,poor integrity,severe de- formation and so on. The characteristics of surrounding rock, occurrence of roof strata, effect of adjacent tunnel and stope face is the main factor causing the roadway difficult to maintain. The technical ideas of reinforcement supporting in stages was put forward, high- strength bolting in stages system of roadway along goaf in coal and mineral coke of symbiosis of coal seam was proposed,including tech- nologies such as pre-grouting,spraying layer to prevent spalling, high strength bolting, supporting in stages. The field practice showed that in 100 days after roadway excavation,the convergence between the two ribs was about 200 mm,the roof subsidence value was about 40 mm,the surrounding rock of roadway tended to stable overall.