综放工作面多巷布置双煤柱合理留设宽度研究

Study on Reasonable Retention Width of Double Pillars in Multi-roadway Layout in Fully Mechanized Working Face

为确保神东保德煤矿81505综放工作面多巷布置方式下巷道的稳定与安全,采用FLAC 3D数值模拟软件,建立数值模拟模型,研究分析了单巷布置方式下沿空煤柱宽度为15.0、20.0、25.0、30.0、35.0 m,以及多巷布置方式下巷间煤柱宽度为7.5、10.0、12.5、15.0、17.5 m时的围岩应力分布、变形及塑性区的分布规律,对比得到沿空煤柱和巷间煤柱的合理尺寸。研究结果表明:在沿空煤柱宽度为25.0 m、巷间煤柱宽度为12.5 m的条件下,煤柱内应力水平较低,煤柱稳定且巷道变形量较小。基于非对称支护原理,提出了适用于保德煤矿81505综放工作面回采巷道的锚网索联合支护方案,工程应用结果表明,工作面回采期间巷道围岩变形可控,煤柱整体稳定,说明所留设的煤柱宽度与支护参数选择合理.

In order to ensure the stability and safety of the roadway under the multi-roadway layout in 81505 fully mechanized working face of Shendong Baode Coal Mine,a numerical test model was established by using FLAC 3D numerical simulation software.The stress distribution,deformation and plastic zone distribution of surrounding rock when the width of gob-side pillar is 15.0 m,20.0 m,25.0 m,30.0 m and 35.0 m under the single roadway layout and the width of pillars between roadways is 7.5 m,10.0 m,12.5 m,15.0 m and 17.5 m under the multi-lane layout were studied and analyzed,the reasonable sizes of gob-side pillars and pillars between roadways were obtained by comparison.The results show that when the width of the gob-side pillar is 25.0 m and the width of the pillar between roadways is 12.5 m,the inner stress level of the coal pillar is low,the coal pillar is stable and the roadway deformation is small.A multi-mode combined support scheme of bolt,mesh and cable based on the principle of asymmetric support was proposed,and the scheme was suitable for the stoping roadway in 81505 fully mechanized working face of Baode Coal Mine.The engineering application results show that the deformation of surrounding rock is controllable and the coal pillar is stable,it means that the retention width and supporting parameters of the coal pillar are reasonable.