三软煤层沿空巷道破坏机制及锚注控制

针对龙口矿区梁家煤矿典型三软地层沿空巷道-4606材料巷围岩控制难题，通过现场监测和试验，分析原支护方案下围岩变形破坏机制。煤层结构复杂，围岩易膨胀、软化，围岩破坏范围大，拱架变形破坏严重，锚杆支护潜力无法有效发挥是巷道变形破坏的主要原因。以锚注支护为核心，实施了U型棚+注浆锚杆+注浆锚索和注浆锚杆+注浆锚索2种联合支护对比试验方案。结果表明：方案实施后，巷道围岩变形量均小于原支护方案37%以上，U型棚+注浆锚杆+注浆锚索联合支护方案中U型棚对围岩的控制作用不明显，注浆锚杆+注浆锚索联合支护完全可以取代传统的U型棚支护。

Gob side entry failure mechanism and control of bolt-grouting inthree soft coal seam

ccording to the field investigation and experiments on a typical gob side entry-material roadway of working face 4606 in Liangjia Coal Mine,the failure mechanism of surrounding rock under original supporting plan was analyzed.The complex structure of coal seam,the easy expansion and softening of surrounding rock,large destruction scope,serious arch deformation,and ineffective support were the main causes of roadway failure.Taken bolt-grouting support as a core measure,two supporting test schemes,namely U type shed+grouting bolt+grouting cable and grouting bolt+grouting cable,were proposed.The results show that the surrounding rock deformations are less than 37% compared with original supporting plan.U type shed does not play an obvious role in controlling surrounding rock,therefore,the grouting bolt + grouting cable can replace U-type shed.