预应力让压锚杆设计参数对深埋巷道稳定性影响分析

Influence of design parameters of prestressed yieldable bolts on stability of deep mine roadway

新型预应力让压锚杆属于一种可延伸锚杆,具有较好的适应围岩变形的能力,在中国一些深埋煤矿巷道支护中得到成功应用。针对这种新型预应力让压锚杆支护系统,考虑围岩层面接触关系、锚杆与围岩接触关系、围岩边界条件以及预应力施加方法,建立了有限元数值模型。以某煤矿巷道支护实例为研究背景,探讨了新型预应力让压锚杆特征参数(让压点和最大让压距离)和设计参数(锚杆间排距、锚杆直径和长度、预应力)对锚杆支护性能的影响,为新型预应力让压锚杆的设计提供参考。

The new prestressed yield bolt(PYB), a kind of extensional bolt, has excellent adaptability to the adjacent rock deformation. The PYB has been applied in the practices of supporting deep coal mine roadways. Considering the interface relationship between rocks, contact relationship between adjacent rocks and bolts, boundary conditions and prestress loading methods, a finite element model for the PYB supporting system is established. A real deep mine roadway supported by the PYB is selected to analyze the effects of performance parameters(yield load and the maximum yield distance) and design parameters(space length, length and diameter of bolt, prestress) of the PYB. The results and conclusions may provide some references to the engineering design of the PYB supporting system.