Stability Analysis of Surrounding Rock and Treatment Structures in Superlarge Karst Cave of Naqiu Tunnel

Figure 11

Vertical stress change of the retaining wall under different working conditions: (a) excavation of 3 m; (b) excavation of 12 m; (c) excavation of 21 m; (d) excavation of 30 m.

(a)

(b)

(c)

(d)