Application of the Upper-Bench CD Method in Super Large-Span and Shallow Tunnel: A Case Study of Letuan Tunnel

Figure 11

Stress of secondary lining steel bar (“+” for tension, “−” for compression, and unit: MPa). (a) Lateral temporal curve. (b) Maximum lateral stress distribution. (c) Medial temporal curve. (d) Maximum stress distribution inside.

(a)

(b)

(c)

(d)