Table 1 Soil group properties
From: Use of a 10.22 m diameter EPB shield: a case study in Beijing subway construction
Soil group | Natural density (g/cm3) | Dry density (g/cm3) | Porosity | Liquid limit (%) | Plastic limit (%) | SPT N-values |
|---|---|---|---|---|---|---|
Backfill | 1.58–1.65 | – | – | – | – | – |
Silt and silty clay | 1.89–2.08 | 1.43–1.76 | 0.349–0.476 | 26.1–40.9 | 17.6–25.4 | – |
Fine and medium sand | 2.02–2.10 | – | – | – | – | 23–53 |