Novel Excavation and Construction Method for a Deep Shaft Excavation in Ultrathick Aquifers

Table 1

Physicomechanical properties of soils at study site.

Soil layer	Average thickness (m)	Unit weight (kN/m^3)	Elastic modulus E (MPa)	Cohesion c (kPa)	Friction angle φ (°)	Hydraulic conductivity k (m/d)
①1 Miscellaneous fill	1.6	18.5	35	5	12	8.5
①2 Plain fill	6.4	18	40	5	10	8.64
②5 Medium-coarse sand	28	19.5	175	2	28	35
③1 Silty clay	1.0	18.6	300	10	20	0.003
③8 Gravel soil	27	21	325	1	35	55
⑦1 Highly weathered granite	—	20.5	600	28	32	0.5