掘采全过程沿空掘巷小煤柱应力分布研究

Stress Distribution of Coal Pillar with Gob-Side Entry Driving in the Process of Excavation & Mining

基于理论分析、FLAC3D数值模拟及现场工程实践的方法,研究了不同宽护巷煤柱沿空掘巷掘采全过程的应力场分布规律,分析了煤柱宽度对沿空掘巷煤柱和实体帮应力演化的影响。提出确定沿空掘巷合理煤柱宽度时,不仅需考虑掘巷扰动影响,还应将本工作面的超前采动影响作为一个重要影响因素。研究结果表明:仅考虑掘巷扰动影响时,沿空掘巷煤柱宽度应大于6 m,此时掘巷稳定后围岩变形量较小;当考虑超前采动影响时,煤柱增加到8 m后不仅对控制回采期间沿空掘巷两帮变形量的作用不再显著增加,反而会使顶底板变形量增大,因此合理的护巷煤柱宽度为8 m。

The stress distribution of coal pillar with different width in the stage of excavation and min- ing was studied based on the theory analysis, numerical simulation, engineering practice, the similarities and differences of stress evolution of coal pillar and entity sidewall caused by different width of coal pillar was analyzed. The opinion was put forward that the infection of roadway driving and coal mining need considered simultaneously when determination the reasonable width for coal pillar. The results show that the proper width of coal pillar should large than six meters for the deformation is attenuation with the increased with of coal pillar. However, the increased width coal pillar such as eight meters not only have reduced contribution ratio to control the sidewall deformation in the stage of coal mining, but also caused top and floor deformation increased. Therefore, the reasonable width of coal pillar is eight meters.