Force and Deformation Characteristics during the Reconstruction and Expansion of Shallow Single-Tube Tunnels into Large-Span Multiarch Tunnels

<div>Time history curves of surrounding rock stresses on the left tunnel side.</div>

Advances in Materials Science and Engineering

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Figure 8

Figure 8: Force and Deformation Characteristics during the Reconstruction and Expansion of Shallow Single-Tube Tunnels into Large-Span Multiarch Tunnels 

Figure 8 | Force and Deformation Characteristics during the Reconstruction and Expansion of Shallow Single-Tube Tunnels into Large-Span Multiarch Tunnels 