为了更好地理解多扰动回采巷道围岩的变化规律,通过对五虎山矿多扰动回采巷道现场观测、钻孔窥视,分析了多扰动巷道围岩变形特征与失稳原因,优化了巷道布置位置,确定了围岩支护方案,并进行了数值模拟与现场试验。结果表明:多扰动巷道顶板浅部围岩破碎度大,呈"网兜"弯曲下沉,两帮整体移动变形,呈反弓形破坏;多煤层开采扰动、顶板岩性软弱、围岩自稳时间短与松动范围大是围岩失稳的原因;上部煤层开采后,由上到下岩层垂直应力由马鞍形向近似拉长"W"形过渡,距上部煤层越远,垂直应力越小,011208运输巷合理位置在010908工作面采空区下方,与010908回风巷外错16 m,煤柱尺寸15 m;采用破碎顶板重点支护(注浆-架棚)与深浅围岩分区承载(锚杆-锚索)耦合控制方案后,巷道围岩变形量小于40 mm,支护效果显著。
In order to understand fully chang law of multiple dynamic tunel,failure characteristics and instability cause of surrounding rock were analyzed by field observation and borehole imaging in multiple dynamic tunnel of Wuhushan mine,the tunnel layout was optimized,the support scheme for surrounding rock was determined,and numerical simulation and field test were conducted. The results showed that shallow roof was broken obviously and subsidence in net. Two sides showed integrate deformation anti-archly. The causes of surrounding rock instability were the effect of multiple seams mined,weak roof,short self-stable course and wide loose range. After the upper seam being mined,vertical stress distribution from the upper to the lower was the variation from a saddle to a similar elongated "W". The longer the distance to the upper seam was,and the smaller vertical stress in the point was. Reasonable location of 011208 haulage gateway was below 010908 working face gob,the distance was 16 m from outside 010908 ventilation gateway,and pillar width was 15 m. After couple controlling scheme of key support on broken roof( grouting-shed) and partition load on deep-shallow surrounding rock( bolt-cable) was used,the deformation of surrounding rock was less than 40 mm,and support effect was significant.