Research Article
Ground Settlements due to Construction of Triplet Tunnels with Different Construction Arrangements
Table 1
PLAXIS 2
D construction phases (Schotte et al. [
24]).
| No. | Phase | Action | Applied pressure (MPa) | Pressure increment (MPa/m) |
| 0 | Initial | — | — | — | 1 | Face pressure, σf | (i) Deactivate soil cluster | | 0.012 | (ii) Apply face pressure | 2 | TBM | (i) Remove face pressure | — | — | (ii) Apply TBM | 3 | Tail pressure 0, σt0 | (i) Remove TBM | | 0.016 | (ii) Apply tail pressure 0 | 4 | Tail pressure 1, σt1 | (i) Apply tail pressure 1 | | 0.011 | 5 | Tail pressure 2, σt2 | (i) Apply tail pressure 2 | | 0.011 | 6 | Final state | (i) Remove tail pressure 2 | — | — | (ii) Activate tunnel lining |
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U, pore water pressure; σa, active earth pressure.
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