Advances in Materials Science and Engineering

Research Article

Surface Settlement Analysis Induced by Shield Tunneling Construction in the Loess Region

Table 1

Physical and mechanics parameters of the tunnel’s surrounding soils.


Soil types	(%)	γ_d (kN/m³)	e₀	c' (kPa)	φ' (°)	c_u (kPa)		K₂₀ × 10⁻⁵ (cm/s)	(10⁻³cm²/s)	E_s (MPa)	(MPa⁻¹)

Miscellaneous fill	22.5	14.8	0.84	—	—	—	—	—	—	5.6	0.54
Plain fill	23.8–25.8	13.9–14.8	0.86–0.96	—	—	15	0.70	—	—	5.3–6.0	0.5–0.7
New loess	24.6–25.4	14.9–15.5	0.76–0.83	35–36	24.1–26.0	20–24	0.65–0.63	1.2–3.5	1.09–2.16	6.8–7.6	0.39–0.44
Saturated loess	25.5	15.7	0.78	35	22.2	26	—	—	—	6.0	0.50
Ancient soil	22.8–24.9	15.8–16.4	0.66–0.73	40	25.0–26.7	25–26	0.62–0.64	2.92	0.96	5.8–7.2	0.42–0.52
Old loess	22.8–23.9	16.0–16.4	0.66–0.70	32–46	20.1–26.4	22–30	0.60–0.69	0.42–6.1	0.12–2.19	6.9–7.1	0.40–0.42
Silty clay	22.0–22.5	16.4–16.6	0.64–0.66	42–50	27.3–29.3	23–35	0.59–0.61	0.01–1.4	1.06–1.92	7.2–7.8	0.38–0.42

Note: the physical meaning of the parameters is, namely, : water content, γ_d: dry bulk density, E_s: compression modulus, e₀: pore ratio, c′ and φ′: index of effective shear strength, : compression coefficient of remorphic loess in the disturbed area, : side pressure coefficient, K₂₀: permeability coefficient, and : consolidation coefficient under nondrainage conditions.