Intelligent Risk Assessment for Dewatering of Metro-Tunnel Deep Excavations

Table 1

Hydraulic and mechanical properties of soil layers of southern airshaft foundation.

No.	Soil layer	Thickness of soil layer (m)	Coefficient of permeability (cm/s)	Modulus of compressibility (MPa)
①1	Miscellaneous fill soil	0.70~3.10	5.0𝐸−03	—
①2	Plain fill soil	0.30~6.00	8.0𝐸−04	6.5
③1	Sandy silt	3.4	4.0𝐸−04	7.0
③2	Sandy silt	3.50~9.70	7.0𝐸−04	8.5
③4	Sandy silt	1.00~5.90	6.5𝐸−04	5.5
③5	Silty sand and sandy silt	1.60~7.00	3.0𝐸−03	7.0
③6	Silt	4.20~10.95	4.0𝐸−03	10.0
③7	Sandy silt	0.80~6.20	2.0𝐸−04	5.5
③8	Silt	—	4.5𝐸−03	10.5
④3	Silty soft clay	2.60~6.70	3.0𝐸−06	2.6
⑥1	Silty soft clay	1.50~3.70	2.0𝐸−06	2.7
⑥2	Silty soft clay	1.00~8.30	5.0𝐸−06	2.8
⑥3	Silt	0.50~3.85	3.0𝐸−03	8.0
⑧2	Silty soft clay	0.80~8.20	4.0𝐸−05	3.0
⑧3	Silty-fine sand	1.80~8.50	5.0𝐸−03	8.5
⑩1	Silty clay	1.90~4.30	8.0𝐸−06	3.2
⑩2	Silty clay	2.80~4.60	4.0𝐸−06	4.5
(14)1	Medium sand	—	6.0𝐸−03	11.0
(14)2	Rounded pebble	—	3.5𝐸−01	—