Effects of Construction Sequences and Volume Loss on Perpendicularly Crossing Tunnels

Table 2

Soil parameters used in finite element analyses.

Description	Parameter
Effective angle of shearing resistance at critical state:	31^°
Coefficient of at rest earth pressure, Ko	0.5
Hardness of granulates, hs	2.6 GPa
Exponent n	0.27
Minimum void ratio at zero pressure, edo	0.61
Maximum void ratio at zero pressure, eio	1.10
Critical void ratio at zero pressure, eco	0.98
Exponent α	0.11
Exponent β	4
Parameter controlling the initial shear modulus upon 180° strain path reversal, mR	8
Parameter controlling the initial shear modulus upon 90° strain path reversal, mT	4
Size of elastic range, R	2 × 10^−5
Parameter controlling the degradation rate of stiffness with strain, βr	0.15
Parameter controlling the degradation rate of stiffness with strain, χ	1.0