Analysis of the Compressibility Effect of Overburden in a Deep Shield Tunnel Based on the Effect of the Pressure Arch

Table 1

Parameters of materials.

Material	Unit weight (kN/m^3)	Elastic modulus (MPa)	Poisson’s ratio	Cohesion (kPa)	Friction angle (°)
Silt	18.7	10	0.38	12	20
Segment	25	3.45 × 10^4	0.18