Failure Mode of Deep Large Section Intersecting Laneway and Its Countermeasures

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.