乌兰木伦煤矿12煤沿空留巷底鼓机理及控制技术研究

Study on floor heave mechanism and control technology of gob-side entry retaining of No.12 coal in Ulan Mulun Coal Mine

当采矿地质条件适宜实施沿空留巷时,可取消工作面区段煤柱,一方面能够大幅度提高煤炭资源回收率,另一方面在掘进队伍紧张时可以更好地安排采掘接替活动。为此,乌兰木伦煤矿在12煤实施了柔模混凝土沿空留巷技术,为控制实施过程中出现的底鼓变形,在调研12407工作面沿空留巷底鼓破坏现象的基础上从机理层面开展了沿空留巷巷道底鼓变形的深层次分析。基于极限平衡理论和滑移场理论进行力学建模,计算得出了采动支承应力作用下沿空留巷巷道底板垂向压力值及最大底鼓压力位置,由此提出了柔模混凝土墙迎山角、临时加强支护优化和打设木点柱等相应的控制措施,控制后的巷道底板平整度良好,能够很好地满足巷道复用需求。

When the mining geological conditions are suitable for the implementation of gob-side entry retaining,the coal pillar in the working face section can be cancelled,which on the one hand can greatly improve the recovery rate of coal resources,and on the other hand can better arrange mining replacement activities if the excavation team is tight.Therefore the flexible form concrete gob-side entry retaining technology was implemented in No.12 coal mine of Ulan Mulun Coal Mine.In order to control the deformation of the floor heave during the implementation process,deep analysis of floor heave deformation of gob-side entry retaining was carried out from the mechanism level based on the investigation of floor heave failure phenomenon of gob-side entry retaining at No.12407 working face.Based on the ultimate equilibrium theory and slip field theory,the mechanical modeling was carried out to calculate the vertical pressure value and maximum floor heave pressure position of gob-side entry retaining floor under the influence of mining support stress.Therefore,corresponding control measures such as mountain facing angle of flexo-mode concrete wall,optimization of temporary strengthening support and measures of laying wooden point column were put forward.After adopting those method,the roadway floor has good roughness,which can meet the needs of roadway reuse well.