Wulanmulun Coal Mine, CHN Energy Shendong Coal Group Co. , Ltd.

重复采动影响下沿空留巷巷道围岩的稳定性控制是确保工作面在采取该成巷布置工艺条件下实现安全回采的重要保障。本研究以乌兰木伦煤矿巷道布置工艺由原双巷掘进向沿空留巷过渡转变条件下,开采12408综采工作面煤体和与12407工作区段遗留的煤柱时面临的留巷围岩破坏失稳问题为工程背景,通过采用现场实测、理论分析和数值模拟的方法对其沿空留巷围岩失稳响应机理进行分析,并提出了采用多举措融合手段技术解决12408外回风巷道剩余段围岩失稳问题。结果表明:二次动压叠加影响作用、基岩岩性特征与埋深的耦合作用、巷道断面支护强度与回采强度参数匹配的不合理性是导致留巷围岩失稳的主要因素;通过采用补强支护+增加单元支架+合理控制回采速度的耦合控制技术体系后,12408工作面剩余段在回采过程中顶离层值为70mm,顶板最大下沉40mm,两帮最大移进量23mm,整体变化较小,围岩变形状态未影响安全回采,变形处于可维控范围。

Wall rock stability control of gob-side roadways under repeated mining is an important guarantee to ensure safe mining of the working face using gob-side entry retaining. We took Wulanmulun Coal Mine as the engineering background, analyzed the problem of surrounding rock failure and instability in the roadway layout process, which was transitioning from the original double roadway excavation to the goaf side roadway, during mining in the coal body of No. 12408 fully mechanized mining face and the remaining coal pillars between No. 12407 working face. By using on - site measurement, theoretical analysis, and numerical simulation methods, the instability response mechanism of the surrounding rock in the goaf side roadway was analyzed, and a multi measure fusion technique was proposed to solve the instability problem of the surrounding rock in the remaining section of No. 12408 outer air return roadway. The results show that the main factors leading to the instability of the surrounding rock in the retained roadway are the influence of secondary dynamic pressure superposition, the coupling effect of bedrock lithology characteristics and burial depth, and the irrational matching of tunnel section support strength and mining strength parameters. After adopting a coupled control technology system of reinforcement support, adding unit supports, and rational control of mining speed, the remaining section of No. 12408 working face has a roof separation value of mm, a maximum subsidence of 40mm on the roof, and a maximum displacement of mm of both sides toward roadway during the mining process. The overall change is relatively small, and the deformation of the surrounding rock does not affect safe mining. The deformation is within a controllable range.

王军,严超超.区段煤柱回收对沿空留巷围岩失稳影响与控制技术研究[J].煤炭工程,2024,56(11):38-45.