Research Article
Analysis on Loose Circle of Surrounding Rock of Large Deformation Soft-Rock Tunnel
Table 3
Initial support parameters table.
| Surrounding rock grade | C30 shotcrete (cm) | Mesh reinforcement (cm) | Anchor (cm) | Steel frames (cm) |
| V | 25 | @20 × 20 | L = 400,@120 × 100 | I20b@80 |
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