Research Article
The Deformation Analysis of a Deep Frame Top-Down Excavation in Downtown Shanghai Based on the 3D FEM
Table 2
Control criteria for protection environment.
| Protection grade | Maximum allowable displacement of the wall | Maximum allowable ground settlement |
| I | 0.18% He | 0.14% He | II | 0.3% He | 0.25% He | III | 0.7% He | 0.55% He |
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