厚表土层薄基岩条件下回采巷道支护研究

Study on Support of Mining Gateway Under Thick Overburden and Thin Base Rock

针对在赵官煤矿3702运输巷掘进过程中,出现剧烈的巷道围岩破坏现象,局部地段需要架设工字钢棚进行二次支护的问题,采用非弹性区理论、有限差分数值计算软件FLAC3D分析确定厚表土层薄基岩的特殊地质条件下合理的巷道支护方案,并在赵官煤矿进行现场工业性试验,以检验支护方案的应用效果。试验证明:高强预应力让压锚杆有效地改善围岩的应力状态,将围岩变形量控制在合理的范围内,使围岩塑性区保持在1.5m。

According to the serious surrounding rock phenomenon of the mining gateway occurred in the driving process of No.3702 transportation gateway in Zhaoguan Mine,a secondary support with the H type steel shields should be conducted in certain section of the gateway.The non elastic regional theory and the finite difference numerical calculation software FLAC3D were applied to analyze and determine the rational support plan of the gateway under the special geological conditions of the thick overburden and thin base rock.A field industrial trial was conducted in Zhaoguan Mine to verify the application effects of the support plan.The trial results showed that the high strength pre-stressed and yield bolt could effectively improve the stress status of the surrounding rock,the deformation value of the surrounding rock could be controlled within the rational scope and the plastic zone of the surrounding rock could be kept within 1.5m.