针对巷道蝶叶塑性区顶板破坏深度大、变形剧烈、冒顶事故频发等问题,综合现场调研、理论分析、数值模拟等方法,考虑巷道顶板不同服务阶段的变形破坏特点,研究分析了巷道顶板破坏失稳机理和不同层位顶板的控制要点,提出了以冒顶控制为主的顶板层次控制技术,阐明了辅助支护材料、普通长度锚杆、接长锚杆、长锚索对不同层位顶板的层次控制原理。据此,在保德矿81306工作面回采巷道蝶叶塑性区顶板进行了层次支护设计,并进行了顶板下沉量和接长锚杆支护力监测,结果表明:以冒顶控制为主的巷道顶板层次支护体系较好的维护了顶板整体稳定,保证了巷道安全与正常服务。
In view of the problems such as large failure depth,severe deformation and frequent roof fall accidents in the roof at the butterfly leaf plastic zone of roadway,the failure and instability mechanism of roadway roof and the control points of roof at different layers were studied and analyzed considering the characteristics of deformation and failure in different service stages of roadway roof through the combined methods of field survey,theoretical analysis and numerical simulation. The multi-level control technology of roof was put forward,which was focused on the roof fall control,and the multi-level control principles of auxiliary support material,ordinary length bolt,lengthening bolt and long anchor cable for the roof at different layers were clarified. On this basis,the multi-level control was designed for the roof at the butterfly leaf plastic zone of mining roadway in 81306 working face of Baode mine,then the roof subsidence and the support force of lengthening bolt were monitored. The results showed that the multi-level support system of roadway roof focusing on the roof fall control maintained the overall stability of roof well,and ensured the safety and normal service of roadway.