Table 1 Physical parameters of two kinds of rock
From: A New System to Evaluate Comprehensive Performance of Hard-Rock Tunnel Boring Machine Cutterheads
Stratigraphic code | Stratum rock | Dry density (g/cm3) | Natural density (g/cm3) | Specific gravity | Natural water absorption rate (%) | Saturated water absorption rate (%) | Longitudinal wave speed of rock (m/s) | Elasticity modulus (GPa) | Poisson ratio μ | Proportion of the whole tunnel (%) |
|---|---|---|---|---|---|---|---|---|---|---|
Pt1x | Migmatite | 2.71 | 2.72 | 2.74 | 0.28 | 0.30 | 4500 | 80 | 0.15 | 11 |
Pt1S | Giant | 2.66 | 2.67 | 2.68 | 0.23 | 0.26 | 5000 | 55 | 0.20 | 89 |