深部超大断面分选硐室群布置方式优化研究

Study on layout optimization of deep super-large section sorting chamber group

为满足井下分选和就地充填要求,井下往往需要密集布置多条硐室,其布置方式对硐室群围岩控制影响重大,是硐室群设计的重要内容。以新巨龙煤矿-800 m水平煤矸分离硐室群为背景,采用理论分析、数值模拟和现场监测相结合,较系统地探讨了硐室群围岩稳定性影响因素,并运用FLAC软件建立数值计算模型,获得了不同布置方式时硐室间距对围岩变形破坏影响规律。随着硐室间距增大,相邻硐室围岩相互影响逐渐减小,同层位布置时最优间距约为15 m,错层位布置时约为18 m。采取同层位布置且硐室间距为15 m时,围岩应力集中区域主要位于硐室交叉处,应力峰值为35 MPa,围岩最大变形量为43 mm,塑性破坏区宽度约为5 m,硐室间存在约5 m见方的弹性承载岩柱。现场工程中4条硐室采用同层位“井字型”布置方式,间距为15~89 m,实践表明:硐室群围岩变形主要集中在硐室成型初期,且以硐室中部变形最大,约为26 mm,围岩整体稳定性好。研究成果可为深埋硐室群布置方式设计及参数优化等提供参考。

In order to meet the requirements of underground sorting and in-situ filling, multiple chambers are usually densely arranged underground. The chamber group layout has a significant impact on the control of surrounding rocks, which is an important content of the chamber group design. Against the background of the-800 m level coal gangue separation chamber group at Xinjulong Coal Mine, theoretical analysis, numerical simulation and field monitoring methods are used to discuss the influence factors of surrounding rock stability. Then the FLACnumerical model is built to get the deformation and failure law with different layout. The results show that the mutual influence of surrounding rocks gradually decreases with the spacing increases. The optimal spacing is about 15 m for the same level layout, and about 18 m for the staggered layout. When the chambers are same level layout with the spacing of 15 m, the stress concentration area of surrounding rock is mainly located at the intersection of chambers with the peak stress 35 MPa, the largest deformation 43 mm and the plastic zone width 5 m, and there are elastic bearing rock pillars about 5 m square between the chambers. In the field practices, four chambers are arranged with a “well-shaped” pattern, and the distances range from 15-89 m. The practices show that the deformation of chamber group is mainly concentrated in the excavation stage, and the largest deformation in the middle is about 26 mm. This research can provide references for the layout design and parameter optimization of deep-buried chamber group.