深部大断面交岔点破坏形式与控制对策

Failure Mode of Deep Large Section Intersecting Laneway and Its Countermeasures

深部大断面交岔点结构复杂、施工扰动次数多,支护难度一般比较大,尤其在牛鼻子部位往往形成尖角,应力集中程度高.通过现场调查交岔点的破坏形式,总结了交岔点不同于普通岩巷的三种破坏形式,分析了各自的破坏机理,并对其支护对策进行初步探讨,认为对牛鼻子截面应限制其最小厚度、对交岔点的大断面区域应限制其最大断面尺寸,并且牛鼻子局部的支护不同于一般软岩巷道,应采用"强支硬顶"的支护思想.试验方案应用于工程实例,取得良好的支护效果.

Being large in section area, complex in structure, and easy to be disturbed, the large section intersecting laneways at depth is very difficult to support, especially in the position where the stress is highly centralized. Through the in-situ investigation in deep laneway intersection, we have summarized three forms of breakage which are different from that of ordinary rock laneways. The causes of each breakage form are analyzed and the supporting process discussed. The result shows that the stress centralized area should not be too flimsy and the section area shouldn＇t be too large; in local stress centralized area it is better to take a strong support. This supporting thinking has been put into operation and obtained a good effect.