特厚煤层错层位巷道布置的沿空掘巷技术研究

Study on gateway driving technology along goaf applied to layout of displaced layer gateway in ultra thick seam

基于特厚煤层错层位巷道布置条件下沿空掘巷技术应用较少的现状,针对错层位沿空掘巷技术展开研究,特厚煤层不同层位布置回采巷道时常留设不同尺寸的三角煤体,采用理论计算的方法对三角煤体的稳定性进行分析,发现在回采14 m特厚煤层时,回采巷道布置在距底板7 m与10.5 m时下方三角煤体处于稳定状态。在此基础上,进一步研究了稳定三角煤体在巷道支护条件下对实体煤稳定性的影响,确定回采巷道布置在距底板10.5 m时,从应力分布与围岩稳定性考虑,可实现完全无煤柱沿空掘巷布置。结果表明:特厚煤层错层位巷道布置条件下沿空掘巷技术,有效改善了沿空掘巷支护与采掘接续问题。

Based on the less application of the gateway driving technology along the goaf under the layout condition of the displaced layer gateway in the ultra thick seam,a study was conducted on the gateway driving technology along the goaf in the displaced layer seam. When a mining gateway made in different layer of the ultra thick seam,different size triangle seam would be left. A theoretical calculation method was applied to the analysis on the stability of the triangle seam. During the mining of the 14 m ultra thick seam,the mining gateway was set in a level with 7 m and 10.5 m to the seam floor and the triangle seam under the level of the gateway was in a stable status. Based on the circumstances,a further study was conducted on the stable triangle seam affected to the stability of the seam under the condition of the gateway support. When the mining gateway layout was determined at a level with a vertical distance of 10.5 m to the seam floor,from the consideration on the stress distribution and the surrounding rock stability,a layout of the gateway driving along the goaf with non coal pillar could be fully realized. The results showed that under the condition of the displaced layer gateway layout in the ultra thick seam,the gateway driving technology along the goaf could effectively improve the support and the mining and driving connection problems of the gateway driving along the goaf.