Identification and Treatment of Collapse and Mud Inrush Caused by Deep Karst Trough in Tunnels

Figure 9

Collapse and mud inrush mode of the filled karst trough: (a) rock mass failure of tunnel face; (b) direct exposure of tunnel face; (c) direct exposure of tunnel roof; (d) rock mass failure of tunnel roof.

(a)

(b)

(c)

(d)