Faculty of Resource and Safety Engineering, China University of Mining &Technology (Beijing)

为了解决困难条件下巷道顶板下沉大、易冒顶的难题,在保德煤矿回采巷道进行了巷道围岩变形与冒顶控制试验,试验结果表明:困难条件下巷道围岩变形相当一部分处于给定变形状态,现有技术水平下支护阻力对围岩变形的控制作用有限;锚索延伸能力较小,无法适应困难条件巷道顶板下沉量大而使锚索大量破断,锚索破断率与顶板下沉量正相关,顶板下沉300 mm以上,锚索破断率可达50%以上;该类巷道支护应摒弃使用锚索刚性大的支护限制变形方法,改用具有高延伸量的对接长锚杆适应此类围岩变形,并持续提供较高支护阻力防止松动围岩冒落引发冒顶。据此提出了用对接长锚杆取代锚索的支护技术,增加支护构件与巷道围岩变形的协调性,保德煤矿工业性试验结果表明,该技术能够适应围岩变形,有效防止锚索破断导致的巷道冒顶。

In order to solve the great deformation and roof caving problems in difficult conditions, field experiments of surrounding rocks deformation and caving co ntrol have been done in Baode mine.Experimental results indicated that a great proportion of surrounding rocks deformation are in a given deformation state, and suppo rt resistance is limitedunder the existing technical level;anchor cable stretching ability is small, which cannot adapt to difficult conditions of large quantities of roadway「 oof subsidence and a lot of anchor cables have been broken.Also, anchor cable breakage rate is positively related to the roof subsidence, and when roof subsidence is above 300 mm, anchor cable breakage rate can reach more than 50%;high-rigid anchor cable supporting method should be abandoned while high-extensive butt long b olt should be applied in roadways to adapt to the deformation of surrounding rock and continue to provide high support resistance to prevent the caving of loose surroun ding rock.Accordingly the authors put forward the support technology of replacing anchor cable with butt long bolt and increasing the coordination of supporting compon ents and roadway deformation.Industrial experiments in Baode mine shows the technology would well adapt to the surrounding rocks deformation and prevent the roof C aving caused by anchor cable breaking.

国家自然科学基金资助项目(51234005)；