Stability of a Rock Tunnel Passing through Talus-Like Formations: A Case Study in Southwestern China

Figure 3

Talus-like rock mass encountered during the tunnel excavation: (a) slate and weak interlayer filled with mudstone at Z5K62 + 936; (b) slate and weak interlayer filled with weathered rock and soft soil at Z5K63 + 966; (c) mixture of slate, limestone, and carbonaceous mudstone at Z5K64 + 455; (d) twisted layers composited by slate and limestone at K62 + 860; (e) isolated rock blocks cut by interlayers filled with weak mudstone at K64 + 530; (f) limestone with carbonaceous mudstone interlayer at K64 + 570.

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