敏东一矿软岩回采巷道底鼓机理及控制对策

Mechanism and control measures of floor heave in soft rock mining roadway in Mindong No.1 Mine

针对敏东一矿软岩回采巷道底鼓严重的问题,采用实验室实验、数值模拟和现场监测等方法,研究了回采巷道底板矿物成分及采动应力对底板变形破坏影响,揭示了软岩回采巷道底鼓机理,并提出了锚杆加固回填支护对策。研究结果表明:巷道底板破坏程度会因与距工作面距离不同而呈现差异化特征,距工作面越近时,采动影响越剧烈,底板破坏程度越高,且会在两帮较高应力挤压作用下向上凸起;同时,底板中含有大量伊利石、蒙脱石矿物成分,在遇水后会发生严重膨胀现象;二者共同影响下,06工作面运输巷易发生“遇水膨胀+挤压流动型”底鼓。

Aiming at the serious floor heave of soft rock mining roadway in Mindong No.1 Mine,using laboratory experiments,numerical simulation and field monitoring methods,the influence of the mineral composition of the mining roadway floor and the mining stress on the deformation and failure of the floor is studied.the mechanism of the floor heave is revealed,and reasonable control measures are proposed.The research results show that,the damage degree of the roadway floor shows different characteristics due to the different distance from the working face.As it gets closer to the working face,the mining impact and floor damage become more severe,and the side walls swell upward under higher stress.At the same time,the floor contains a lot of illite and montmorillonite,which expand seriously after encountering water;under the influence of the two factors,the 06 working face transportation lane is prone to“water expansion+squeeze flow type”floor heave.Based on the research results,the over-excavated bolt reinforcement and backfill support measures are proposed.