Comparative Study on Grouting Protection Schemes for Shield Tunneling to Adjacent Viaduct Piles

Table 1

Physical mechanical parameters of surrounded layers.

Soil type at each layer	Thickness H (m)	Elasticity modulus E (MPa)	Poisson’s ratio μ	Unit weight γ (kN·m^−3)	Cohesion c (kPa)	Internal friction angle φ (°)	Permeability coefficient k (m·d^−1)
① Miscellaneous fill	7.8	8.5	0.35	19.0	10	12	0.700
② Silty clay	3.2	15.5	0.30	20.0	30	16	0.008
③ Pebble	2.9	35.0	0.25	20.0	2	36	25.000
④ Highly weathered conglomerate	23.0	38.5	0.27	23.5	40	30	0.500
⑤ Moderately weathered conglomerate	33.1	47.0	0.24	25.0	120	35	0.100